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To develop special insulating paper is of great significance to promote the service life of transformers. Using molecular simulation to guide the development of special insulating paper can greatly reduce the trial-and-error rate and waste of resources in traditional experiments. The effect of different types of polysilsesquioxane (POSS) on cellulose insulating paper was investigated by using molecular simulation. This paper investigated the thermal stability and mechanical properties and electrical characteristics of caged POSS, semi-caged POSS, and ladder-like POSS doped cellulose insulating paper. The results show that POSS with all types can enhance the performance of cellulose insulating paper, and ladder-like POSS possess the best modification effect. The glass transition temperature was increased by 58 K, and the bulk modulus, shear modulus, and elastic modulus of cellulose insulating paper doped with ladder-like POSS can improve up to 27.07%, 45.67%, and 41.28%, respectively. Meanwhile, the dielectric properties of ladder-like POSS modified insulating paper are also significantly improved. The findings of this paper propose a method for the preparation of ladder-like POSS modified insulating paper, which provides theoretical guidance for the experimental preparation of special insulating paper. [ABSTRACT FROM AUTHOR]

Pustular mats from Shark Bay, Western Australia, host complex microbial communities bound within an organic matrix. These mats harbour many poorly characterized organisms with low relative abundances (

Cellulose nanocrystals (CNC) and nanofibers (CNF) have been broadly studied as renewable nanomaterials for various applications, including additives in cement and plastics composites. Herein, life cycle inventories for 18 previously examined processes are harmonized, and the impacts of CNC and CNF production are compared with a particular focus on GHG emissions. Findings show wide variations in GHG emissions between process designs, from 1.8-1100 kg CO2-eq/kg nanocellulose. Mechanical and enzymatic processes are identified as the lowest GHG emission methods to produce CNCs and CNFs. For most processes, energy consumption and chemical use are the primary sources of emissions. However, on a mass basis, for all examined production methods and impact categories (except CO emissions), CNC and CNF production emissions are higher than Portland cement and, in most cases, are higher than polylactic acid. This work highlights the need to carefully consider process design to prevent potential high emissions from CNCs and CNF production despite their renewable feedstock, and results show the magnitude of conventional material that must be offset through improved performance for these materials to be environmentally favorable.

We report on the studies of conduction mechanism, direct current conductance, and 1 f -noise of cellulose nanofiber (CNF) and multiwalled carbon nanotube (MWCNT) composites. The composites were characterized by x-ray diffraction, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. The temperature- and voltage-dependence of the dc conductance Σ were, respectively, probed to investigate the charge transport mechanism and the electrical response of the composite. At room temperature, the increase in Σ with wt. % of MWCNT ϕ showed typical percolation behavior. The Σ − T behavior was fitted to the combination of one-dimensional variable range hopping and the fluctuation-induced tunneling, which were attributed to hopping of charge carriers through 1D MWCNTs and the tunneling of charge carriers between the bundles of MWCNTs, respectively. The non-Ohmic electrical conduction was characterized by the onset voltage V 0 (T) which scaled with Ohmic conductance Σ 0 as V 0 (T) ∼ Σ 0 (T) x T , with x T being the onset exponent increased with ϕ. A scaling description based on the data collapse method was adopted to find the parameters V 0 (T) and x T. The noise power spectrum S V (f) followed the relation S V (f) ∼ V β with two different power-laws: β 1 in the Ohmic and β 2 in the non-Ohmic region (β 1 > --> β 2). Interestingly, this change in power-laws occurs at the same V 0 (T) obtained from Σ − V curves. A simple model was proposed to explain the noise behavior after V 0 (T). It is expected that such electrical characterization of CNF-MWCNT nanopaper composite would open up their possibility of application in flexible electronic devices, intelligent networks, sensors, and actuators. [ABSTRACT FROM AUTHOR]

Using Onsager–Straley's second-virial theory, we investigate the cholesteric pitch of cellulose nanocrystal (CNC) suspensions. We model the CNCs as hard chiral bundles of microfibrils and examine the effect of the shape of these chiral bundles, characterized by aspect ratio and chirality, on the cholesteric pitch. Additionally, we explore the impact of length polydispersity and surface charge on the cholesteric phase of CNCs. Furthermore, we consider binary mixtures of twisted bundles and achiral primary crystallites to provide a more realistic representation of CNC suspensions. Our findings reveal that the degree of bundle twisting significantly affects the helical twisting of the cholesteric phase. We also observe that the average particle length and length polydispersity have substantial effects on strongly twisted bundles but minimal effects on weakly twisted ones. Finally, our study indicates that as the range of electrostatic interactions increases, the transfer of chirality from the microscopic to macroscopic length scales becomes masked, resulting in an increase in the cholesteric pitch. In the case of binary mixtures, the bundles act as chiral dopants, and an increasing fraction of bundles progressively enhances the helical twisting of the cholesteric phase. [ABSTRACT FROM AUTHOR]

Identification of the core functional microorganisms in food fermentations is necessary to understand the ecological and functional processes for making those foods. Wheat qu, which provides liquefaction and saccharifying power, and affects the flavor quality, is a key ingredient in ancient alcoholic huangjiu fermentation, while core microbiota of them still remains indistinct. In this study, metagenomics, metabolomics, microbial isolation and co-fermentation were used to investigate huangjiu. Although Aspergillus is usually regarded as core microorganism in wheat qu to initiate huangjiu fermentations, our metagenomic analysis showed that bacteria Saccharopolyspora are predominant in wheat qu and responsible for breakdown of starch and cellulose. Metabolic network and correlation analysis showed that Saccharopolyspora rectivirgula, Saccharopolyspora erythraea, and Saccharopolyspora hirsuta made the greatest contributions to huangjius metabolites, consisting of alcohols (phenylethanol, isoamylol and isobutanol), esters, amino acids (Pro, Arg, Glu and Ala) and organic acids (lactate, tartrate, acetate and citrate). S. hirsuta J2 isolated from wheat qu had the highest amylase, glucoamylase and protease activities. Co-fermentations of S. hirsuta J2 with S. cerevisiae HJ resulted in a higher fermentation rate and alcohol content, and huangjiu flavors were more similar to that of traditional huangjiu compared to co-fermentations of Aspergillus or Lactiplantibacillus with S. cerevisiae HJ. Genome of S. hirsuta J2 contained genes encoding biogenic amine degradation enzymes. By S. hirsuta J2 inoculation, biogenic amine content was reduced by 45%, 43% and 62% in huangjiu, sausage and soy sauce, respectively. These findings show the utility of Saccharopolyspora as a key functional organism in fermented food products.

The efficient and simple separation of oil-water mixtures has been a global challenge due to the growing problem of oily wastewater. To address this issue, various materials with special wetting properties and functionality have been developed in the past decades for oil-water separation. In this study, a super-hydrophobic cellulose acetate (CA) functional coating was prepared by electrostatic spraying of CA and chemical vapor deposition of methyltrichlorosilane (MTCS) on a stainless steel mesh (SSM). Water contact angle in air (WCA) of the resulting coating is 154[degrees] or more, and oil under water contact angle (UWOCA) is 0[degrees]. Simultaneously, the separation flux of the resulting coating for oil-water mixtures is as high as 23977.77 L*[m.sup-2]*[h.sup.-1], with separation efficiencies exceeding 99%. Due to its excellent water repellency, the CA functional coating can effectively separate oil and water, and can be easily dried for continuous use. Furthermore, the CA functional coating exhibits good stability in salt solutions and acidic environments, making it an ideal material for addressing oily wastewater challenges. Highlights * The coating obtained by electrostatic spraying and CVD was superhydrophobic. * The separation flux and separation efficiencies of coatings is 23977.77 L*[m.sup-2]*[h.sup.-1] and 99%. * Coatings remain stable under polar environment conditions (pH = 2-12 and NaCl = 1-3 mol/L). KEYWORDS cellulose acetate, chemical vapor deposition, electrostatic spraying, oil-water separation, superhydrophobic, 1 | INTRODUCTION The rapid rise of the petrochemical industry in recent decades has contributed to the industrial revolution and the progress of human society, (1) but it has also [...]

Lignocellulose, as the most abundant natural organic carbon on earth, plays a key role in regulating the global carbon cycle, but there have been only few studies in marine ecosystems. Little information is available about the extant lignin-degrading bacteria in coastal wetlands, limiting our understanding of their ecological roles and traits in lignocellulose degradation. We utilized in situ lignocellulose enrichment experiments coupled with 16S rRNA amplicon and shotgun metagenomics sequencing to identify and characterize bacterial consortia attributed to different lignin/lignocellulosic substrates in the southern-east intertidal zone of East China Sea. We found the consortia enriched on woody lignocellulose showed higher diversity than those on herbaceous substrate. This also revealed substrate-dependent taxonomic groups. A time-dissimilarity pattern with increased alpha diversity over time was observed. Additionally, this study identified a comprehensive set of genes associated with lignin degradation potential, containing 23 gene families involved in lignin depolymerization, and 371 gene families involved in aerobic/anaerobic lignin-derived aromatic compound pathways, challenging the traditional view of lignin recalcitrance within marine ecosystems. In contrast to similar cellulase genes among the lignocellulose substrates, significantly different ligninolytic gene groups were observed between consortia under woody and herbaceous substrates. Importantly, we not only observed synergistic degradation of lignin and hemi-/cellulose, but also pinpointed the potential biological actors at the levels of taxa and functional genes, which indicated that the alternation of aerobic and anaerobic catabolism could facilitate lignocellulose degradation. Our study advances the understanding of coastal bacterial community assembly and metabolic potential for lignocellulose substrates. IMPORTANCE It is essential for the global carbon cycle that microorganisms drive lignocellulose transformation, due to its high abundance. Previous studies were primarily constrained to terrestrial ecosystems, with limited information about the role of microbes in marine ecosystems. Through in situ lignocellulose enrichment experiment coupled with high-throughput sequencing, this study demonstrated different impacts that substrates and exposure times had on long-term bacterial community assembly and pinpointed comprehensive, yet versatile, potential decomposers at the levels of taxa and functional genes in response to different lignocellulose substrates. Moreover, the links between ligninolytic functional traits and taxonomic groups of substrate-specific populations were revealed. It showed that the synergistic effect of lignin and hemi-/cellulose degradation could enhance lignocellulose degradation under alternation of aerobic and anaerobic conditions. This study provides valuable taxonomic and genomic insights into coastal bacterial consortia for lignocellulose degradation.

The plant secondary cell wall is a thickened matrix of polysaccharides and lignin deposited at the cessation of growth in some cells. It forms the majority of carbon in lignocellulosic biomass, and it is an abundant and renewable source for forage, fiber, materials, fuels, and bioproducts. The complex structure and arrangement of the cell wall polymers mean that the carbon is difficult to access in an economical and sustainable way. One solution is to alter the cell wall polymer structure so that it is more suited to downstream processing. However, it remains difficult to predict what the effects of this engineering will be on the assembly, architecture, and properties of the cell wall. Here, we make use of Arabidopsis plants expressing a suite of genes to increase pectic galactan chain length in the secondary cell wall. Using multi-dimensional solid-state nuclear magnetic resonance, we show that increasing galactan chain length enhances pectin-cellulose spatial contacts and increases cellulose crystallinity. We also found that the increased galactan content leads to fewer spatial contacts of cellulose with xyloglucan and the backbone of pectin. Hence, we propose that the elongated galactan side chains compete with xyloglucan and the pectic backbone for cellulose interactions. Due to the galactan topology, this may result in comparatively weak interactions and disrupt the cell wall architecture. Therefore, introduction of this strategy into trees or other bioenergy crops would benefit from cell-specific expression strategies to avoid negative effects on plant growth.

Biofoam products have attracted considerable attention lately because there is a growing demand for green/sustainable products. To this end, various biobased foams have either been developed or are currently in development, e.g., bio-based polyurethanes (PUs), polylactic acid (PLA), starch, and polyhydroxyalkanotates (PHAs). Indeed, significant progress has been made; however, challenges still persist, for example, biobased foam products have poor processability, inferior compatibility, thermal and strength properties. In this review, we focus on five biofoam products: namely bio-based PUs, PLA, starch, PHAs, and cellulose biofoam products, along with their properties and performance, as well as their manufacturing processes. Further efforts are still needed to unlock the full potential of these bio-based products and meet the goal of complementing and gradually replacing some of their fossil-based counterparts. Finally, the challenges, as well as arising opportunities of future research directions are discussed.

Non-degradable polymers cause serious environmental pollution problem, such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products. It is imperative and attractive to develop biodegradable functional coatings. Herein, we proposed a novel strategy to successfully prepare biodegradable, thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose chain. The natural cellulose and cinnamic acid were as raw materials. Via reducing the degree of polymerization (DP) of cellulose and regulating the degree of substitution (DS) of cinnamate moiety, the obtained cellulose cinnamate (CC) exhibited not only the thermal flow behavior but also good biodegradability, which solves the conflict between the thermoplasticity and biodegradability in cellulose-based materials. The glass transition temperature (Tg) and thermal flow temperature (Tf) of the CC could be adjusted in a range of 150–200 °C and 180–210 °C, respectively. The CC with DS

Abstract Background Microbial expansins (EXLXs) are non-lytic proteins homologous to plant expansins involved in plant cell wall formation. Due to their non-lytic cell wall loosening properties and potential to disaggregate cellulosic structures, there is considerable interest in exploring the ability of microbial expansins (EXLX) to assist the processing of cellulosic biomass for broader biotechnological applications. Herein, EXLXs with different modular structure and from diverse phylogenetic origin were compared in terms of ability to bind cellulosic, xylosic, and chitinous substrates, to structurally modify cellulosic fibrils, and to boost enzymatic deconstruction of hardwood pulp. Results Five heterogeneously produced EXLXs (Clavibacter michiganensis; CmiEXLX2, Dickeya aquatica; DaqEXLX1, Xanthomonas sacchari; XsaEXLX1, Nothophytophthora sp.; NspEXLX1 and Phytophthora cactorum; PcaEXLX1) were shown to bind xylan and hardwood pulp at pH 5.5 and CmiEXLX2 (harboring a family-2 carbohydrate-binding module) also bound well to crystalline cellulose. Small-angle X-ray scattering revealed a 20–25% increase in interfibrillar distance between neighboring cellulose microfibrils following treatment with CmiEXLX2, DaqEXLX1, or NspEXLX1. Correspondingly, combining xylanase with CmiEXLX2 and DaqEXLX1 increased product yield from hardwood pulp by ~ 25%, while supplementing the TrAA9A LPMO from Trichoderma reesei with CmiEXLX2, DaqEXLX1, and NspEXLX1 increased total product yield by over 35%. Conclusion This direct comparison of diverse EXLXs revealed consistent impacts on interfibrillar spacing of cellulose microfibers and performance of carbohydrate-active enzymes predicted to act on fiber surfaces. These findings uncover new possibilities to employ EXLXs in the creation of value-added materials from cellulosic biomass.

L-lysine functionalized cellulose-based lead adsorbents were prepared. The microcrystalline cellulose (MCC) and cellulose nanofiber (CNF) were performed as the matrix and L-lysine was used as the grafted monomer. In this study, the adsorption performance of the adsorbents for lead in fruit juice was explored. And the effects of sugars and organic acids on adsorption properties in fruit juice were deeply explored. Both L-lysine functionalized sodium periodate-oxidized-MCC (L-g-POCM) and L-lysine functionalized tetramethylpiperidine system-oxidized-CNF (L-g-TOCF) had excellent adsorption efficiency on lead ions, reaching 77.36% and 96.16%, respectively. The sugar solution was neutral. It had weak competitive adsorption with lead ions. The organic acids with high acidity had strong competitive adsorption with lead ions. Compared with L-g-POCM, L-g-TOCF was less affected. At pH less than 4, the adsorption efficiency of L-g-TOCF was strongly inhibited, as low as 7.54%. When pH greater than 4, it reached up to 92.18%. Thus, L-g-TOCF have a promising prospect of removal heavy metals in low-acid fruit juices.

Abstract The demand for high-purity cellulose, optimization of wood utilization, and environmentally friendly processes has increased in dissolving pulp (DP) production. Sago palm fronds (SPF), an abundant agricultural waste in Indonesia, hold great potential as a raw material for cellulose, hemicellulose, and lignin production. This study aimed to explore the production of from SPF by employing a combination of prehydrolysis, soda cooking with 2-methylanthraquinone (MAQ) as a green additive (PHS-MAQ), and totally chlorine-free (TCF) bleaching with peroxymonosulfuric acid (Psa). Furthermore, lignin was recovered from the black liquor of PHS-MAQ. The results showed that prehydrolysis at 150 ºC for 3 h, followed by soda-MAQ cooking at 160 ºC for 1.5 h using 0.03% of MAQ, 23% active alkali (AA), and a five-stage bleaching with oxygen (O), Psa, alkaline extraction with hydrogen peroxide (Ep), Psa, and Ep successfully produced high-purity cellulose as DP, with properties of 94.3% α-cellulose content, 89.9% ISO brightness (SNI ISO 2470–1:2016), 9.1 cP viscosity, and 0.13% ash content. Moreover, the soda-MAQ cooking method exhibited superior delignification compared to prehydrolysis kraft (PHK) and prehydrolysis soda (PHS) processes in a range of kappa numbers of 9.4–22.6 at 17–25% AA. The inclusion of MAQ increased pulp yields by 4.6–4.9% and decreased kappa number by 1.6–3.1 compared to the PHS without additives at similar AA. Lignin was separated from the PHS-MAQ, with yields of 69–77%. This work demonstrated the suitability of SPF processed by PHS-MAQ cooking and Psa bleaching for the preparation of viscose rayon and cellulose derivatives. The lignin recovery could be an attractive biorefinery process in modern pulp mills.

Highlights A bionic phase-locked structure-inspired iontronic triboelectric gel is proposed with good mechanical compliance for wearable haptic sensing applications. Competitive hydrogen bonding systems are constructed through polymer-solvent-nonsolvent interactions, and regeneration of polymers with weak hydrogen bond donors triggers controlled phase separation. Self-powered haptic skin constructed with iontronic triboelectric gel has a modulus (150.6 kPa) and stretchability (> 400%) similar to that of the human body, enabling fidelity transmission of haptic signals and precise recognition of sensing objects.

Abstract Background The tunicates form a group of filter-feeding marine animals closely related to vertebrates. They share with them a number of features such as a notochord and a dorsal neural tube in the tadpole larvae of ascidians, one of the three groups that make tunicates. However, a number of typical chordate characters have been lost in different branches of tunicates, a diverse and fast-evolving phylum. Consequently, the tunic, a sort of exoskeleton made of extracellular material including cellulose secreted by the epidermis, is the unifying character defining the tunicate phylum. In the larva of ascidians, the tunic differentiates in the tail into a median fin (with dorsal and ventral extended blades) and a caudal fin. Results Here we have performed experiments in the ascidian Phallusia mammillata to address the molecular control of tunic 3D morphogenesis. We have demonstrated that the tail epidermis medio-lateral patterning essential for peripheral nervous system specification also controls tunic elongation into fins. More specifically, when tail epidermis midline identity was abolished by BMP signaling inhibition, or CRISPR/Cas9 inactivation of the transcription factor coding genes Msx or Klf1/2/4/17, median fin did not form. We postulated that this genetic program should regulate effectors of tunic secretion. We thus analyzed the expression and regulation in different ascidian species of two genes acquired by horizontal gene transfer (HGT) from bacteria, CesA coding for a cellulose synthase and Gh6 coding for a cellulase. We have uncovered an unexpected dynamic history of these genes in tunicates and high levels of variability in gene expression and regulation among ascidians. Although, in Phallusia, Gh6 has a regionalized expression in the epidermis compatible with an involvement in fin elongation, our functional studies indicate a minor function during caudal fin formation only. Conclusions Our study constitutes an important step in the study of the integration of HGT-acquired genes into developmental networks and a cellulose-based morphogenesis of extracellular material in animals.

In order to compare the effects of different enzyme pretreatments on the quality of fruit fermented Jiaosu. Bananas were used as raw materials in this paper. Cellulase, pectinase and papain were used to pretreat bananas, and the effects of different enzyme pretreatments on the physical and chemical indexes, antioxidant, sensory of banana enzyme were compared. The results showed that enzyme treatment had little effect on pH and total acid. The ability of reducing sugar utilization in the enzyme pretreatment group was significant, and the final sugar content was reduced by about 10 g/L. At 72 h of fermentation, the total phenolic content of cellulase and papain treatment groups was significantly increased by about 1.31 times (P

Sulfonated polysulfone (SPS) composite membranes consisting of cellulose-based carbon nanodots (CNDs) were successfully prepared as a proton exchange membrane (PEM) for direct methanol fuel cell (DMFC) applications. The CNDs were prepared using the top-down hydrothermal method. The structure transformation from cellulose to CNDs was confirmed by the FTIR and XRD analysis. The particle size of CNDs was between 1 and 3 nm. The particles exhibited good optical properties. The incorporation of CND into matrix polymer increased the thermal stability of the membranes. Morphology analysis of the SPS/CND composite membranes revealed that CNDs had been successfully dispersed within the SPS polymer matrix. The cross-linking between SPS and CNDs enhanced the proton conductivity of the composite membranes compared to the pristine SPS membrane. The SPS/CND-1 (1 wt%) exhibited the highest selectivity with a proton conductivity of 35.5 mS.cm−1 and a methanol permeability of 3.50 × 10−6 cm2.s−1. The experimental results indicate that the incorporation of CNDs into the SPS membrane also decreased the amount of methanol that can pass through the membrane when used in DMFCs.

Abstract In this study, the biodegradability of cellulose films was evaluated in controlled-moisture soil environments. The films were prepared from low-quality cotton fibers through dissolution in DMAc/LiCl, casting, regeneration, glycerol plasticization, and hot-pressing. Two soil burial degradation experiments were conducted in August 2020 (11th August to 13th October) and March 2021 (24th March to 24th July) under controlled moisture conditions to assess the biodegradation behavior of cellulose films. The films were retrieved from soil beds at seven-day intervals, and morphological and physicochemical changes in the films were investigated. The results indicated that the cellulose films exhibited gradual changes starting on Day 7 and major changes after Day 35. Stereomicroscopy images showed the growth and development of fungal mycelia on the surface of the films, and FTIR spectroscopy confirmed the presence of biomolecules originating from microorganisms. The tensile strength and elongation of cellulose films were significantly reduced by 64% and 96% in the first experiment and by 40% and 94% in the second experiment, respectively, during the degradation period. Degradation also significantly impacted the thermal stability (14% and 16.5% reduction, respectively, in the first and second studies) of the films. The cellulose-based films completely degraded within 63 days in late summer and 112 days in spring. This study demonstrates that, unlike synthetic plastics, films prepared from low-quality cotton fibers can easily degrade in the natural environment.

Highlights Enhancing rate performance of cellulose-derived hard carbon anodes from the view of cellulose molecular, crystalline, and aggregation structure is explored. Relationship of storage sodium and rate performance according to theoretical calculation and characterization analysis is illustrated. Cellulose intrinsic microstructure, conversion relationship between the allotropes of cellulose, and the critical influences on cellulose-derived carbon structure are discussed.