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The microscopically structural switching of supramolecular networks endows programmable gel materials with dynamic hiding properties and functionalities. However, the reconstruction of supramolecular network will destroy the programming information imprinted on the original network structure, making it difficult to restore to the original state. Here, a novel intelligent programmable photonic gel composed of cellulose nanocrystals (CNC) and acrylamide is constructed. The mechanical properties and optical signals of gel can be switched reversibly on demand by reasonably designing the winding and compression between molecular structures. Under this conversion mechanism, the rigid "skeleton" constructed from the CNC chiral structure perfectly acts as the coding substrate. Importantly, even after multiple dynamic switching of the supramolecular network, the encoded information can be displayed completely and accurately on the CNC chiral structure in the stretched state. In addition, the 5D controllable conversion of stiffness, transparency, stretchability, color, and shape greatly improves the security and confidentiality of the encoded information inside the gel. This is a successful example of the application of CNC chiral structure in switchable supramolecular network materials. It is believed that the flexible variability and advanced camouflage give the intelligent gel the potential to be used in a wider range of practical scenarios. [ABSTRACT FROM AUTHOR]

Given the widespread prevalence of viruses, there is an escalating demand for antimicrobial composites. Although the composite of dialdehyde cellulose and silver nanoparticles (DAC@Ag1) exhibits excellent antibacterial properties, its weak mechanical characteristics hinder its practical applicability. To address this limitation, cellulose nanofibers (CNFs) were initially ammoniated to yield N-CNF, which was subsequently incorporated into DAC@Ag1 as an enhancer, forming DAC@Ag1/N-CNF. We systematically investigated the optimal amount of N-CNF and characterized the DAC@Ag1/N-CNF using FT-IR, XPS, and XRD analyses to evaluate its additional properties. Notably, the optimal mass ratio of N-CNF to DAC@Ag1 was found to be 5:5, resulting in a substantial enhancement in mechanical properties, with a 139.8% increase in tensile elongation and a 33.1% increase in strength, reaching 10% and 125.24 MPa, respectively, compared to DAC@Ag1 alone. Furthermore, the inhibition zones against Escherichia coli and Staphylococcus aureus were significantly expanded to 7.9 mm and 15.9 mm, respectively, surpassing those of DAC@Ag1 alone by 154.8% and 467.9%, indicating remarkable improvements in antimicrobial efficacy. Mechanism analysis highlighted synergistic effects from chemical covalent bonding and hydrogen bonding in the DAC@Ag1/N-CNF, enhancing the mechanical and antimicrobial properties significantly. The addition of N-CNF markedly augmented the properties of the composite film, thereby facilitating its broader application in the antimicrobial field. [ABSTRACT FROM AUTHOR]

The challenge in energy depletion and environmental pollution urgently demands green and sustainable materials as a new material application platform. Nanocellulose (NC) derived from abundant and renewable resources has been considered as a versatile and sustainable substrate and scaffold to engage various applications. Recently, design and fabricate conductive polymers (CPs)/NC composites as functional electronic devices have received tremendous attention. In this mini review, we start with a brief introduction about the category of nanocellulose, CPs and the preparation strategy of CPs/NC conducive composites followed by discussing the factors that determine the electrical conductivity. Then, we reviewed different CPs/NC composites systems and cited representative electronic application examples including sensors, supercapacitors, lithium-ion batteries. Finally, we proposed current challenges, existing problems and further perspectives and opportunities of CPs/NC conductive composites. [ABSTRACT FROM AUTHOR]

Shale gas resource is heterogeneously distributed in Permian Gufeng Formation in the Xuancheng area, Anhui Province. This research aims to investigate the pore size distribution of the Permian Gufeng shales via 16 core samples analyses, combined with x‐ray diffraction, low‐pressure nitrogen gas adsorption (N2‐GA), CO2 gas adsorption (CO2‐GA) and scanning electron microscopy (SEM). N2‐GA shows that the nanopores (diameter < 10 nm) are dominated and developed in the samples. The Brunauer–Emmett–Teller (BET) specific surface area (SSA) of the samples ranges from 6.7051 to 29.4384 m2/g, with a mean of 16.0931 m2/g. CO2‐GA results illustrate that micropore is well developed, especially the pores with a diameter of 0.5–0.6 and 0.8 nm. The total organic carbon (TOC) content of the Gufeng shale ranges from 0.42% to 12.82% with an average content of 6.44%, which has both positive correlation with pore SSA and pore volume, while carbonate mineral content has a positive correlation with pore SSA and the volume of macropore and mesopore. Clay mineral content is a negative correlation with pore SSA and micropore volume. Therefore, the high‐maturity Permian Gufeng shale could be more preferential high‐quality gas shale reservoir for further exploration and development in the Xuancheng area, which has more than 4% TOC content, relatively higher carbonate mineral content and relatively lower clay mineral content. [ABSTRACT FROM AUTHOR]

The fast growth of micro-flexible electronic devices has increased the amount of heat generated and electronic waste, which has increased the demand for eco-friendly nanocellulose-based composites with great flame resistance and strong thermal conductivity. Nevertheless, creating appropriate thermally conductive fillers and enhancing the flame retardancy of materials based on nanocellulose remain extremely difficult tasks. This study describes the production of extremely in-plane oriented composite films using TEMPO-oxidized nanocellulose (TOCNF) as the matrix, boron nitride nanosheets (50 wt% BNNS@PDA) as the filler for thermal conductivity, and a small number of phosphorus lignin nanoparticles (2 wt% PL) as an auxiliary filler. First, the orderly organization of thermally conductive fillers in the composite film may be achieved using one-step ball milling, stripping, and non-covalent modification of hexagonal boron nitride, offering an efficient thermal conductivity channel to raise thermal conductivity. After filling in PL (2 wt%), due to the highly compact oriented structure and rich flame-retardant functional groups, the thermal conductivity and flame-retardant properties of the composite film are improved at the same time. The final results demonstrate that the composite film exhibits a high thermal conductivity of 23.49 W mK−1. Compared with a pure nanocellulose film, the TOCNF/BNNS@PDA/PL composite film has a better flame retardant effect and thermal stability. In addition, the composite films show satisfactory flexibility and mechanical properties due to their tight structure and strong interfacial interactions. In conclusion, this work provides a feasible solution for the application of nanocellulose-based thermal conductivity and flame-retardant dual-function composites in thermal management applications for next-generation flexible electronic devices. [ABSTRACT FROM AUTHOR]

To shield significantly serious radiation pollution and reduce fire disasters, fire-retardant MXene-based electromagnetic interference (EMI) shielding nanocomposites featuring superb mechanical properties are highly desired, but remain a major challenge to prepare. Here, we propose a Janus structural engineering strategy to manufacture all-natural cellulose nanofiber (CNF)/montmorillonite (MMT)-supported MXene papers (CMMPs) using a sequential deposition followed by hot-pressing. Inspired by natural nacre, MMT nanosheets are incorporated into CNFs to construct a substrate layer with a "brick-mortar" layered structure that serves to provide mechanical properties, while the independent MXene layer ensures electrical conductivity. The resultant CMMPs exhibit extraordinary mechanical performances involving a mechanical strength of 272.7 MPa and Young's modulus of 10.8 GPa, high electrical conductivity, and a superb EMI shielding effectiveness of 56.1 dB and EMI SE/t of 19 140.8 dB cm−1. Moreover, the designed CMMPs possess impressive flame-retardant and electro-/photothermal heating features, demonstrating their reliability, safety, and versatility. Therefore, such high-performance CMMPs developed by a facile and sustainable preparation strategy possess substantial application prospects in EMI shielding, thermal management, and fire protection. [ABSTRACT FROM AUTHOR]

High-performance materials with versatile functionalities are highly desirable for modern electronic devices. Inspired by natural nacre with a layered aragonite platelet/chitin nanofiber/protein ternary structure, a high-strength nanopaper is fabricated by introducing two-dimensional (2D) montmorillonite (MTM) nanoplates and 1D cellulose nanofibrils (CNFs) into a 3D aramid nanofiber (ANF) framework via vacuum filtration. The obtained ANF/MTM/CNF nanopapers yield record-high tensile strength (δc) (484.58 MPa) and outstanding toughness (εc) (53.70 MJ m−3). Furthermore, the incorporation of Ag nanowires (AgNWs) enables the nanopapers to achieve high heating temperatures (up to ∼200 °C) and satisfactory electromagnetic interference shielding effectiveness (24.14 dB). Moreover, the ANF/MTM/CNF/AgNW nanopapers maintain excellent mechanical properties, where their δc and εc are 488.48 MPa and 52.74 MJ m−3. Normalized by weight, the specific tensile strength of the nanopapers reaches 359 MPa g−1 cm3, that is even superior to that of a commercial titanium alloy (257 MPa g−1 cm3). Besides, the nanopapers have outstanding mechanical durability, in which, being electrically heated at 170 °C for 1 h, the nanopapers still retain 93.69% of the original δc. This bioinspired nanopaper presents a novel approach to create mechanically strong nanopapers with diverse outstanding functionalities, catering to the demands of high-end electronics. [ABSTRACT FROM AUTHOR]

Carbon reduction targets urge people to develop potential alternatives to traditional energy-intensive kraft pulping. To address this need, this work reported a sustainable pulping technology for eucalyptus slabs based on a deep eutectic solvent (DES) consisting of benzyltriethylammonium chloride (BTEAC) and formic acid (FA). Under mild cooking conditions (T = 130 °C, t = 2.0 h), the pulp yield reached 53.83%, and fibers had a length of 0.65 mm and a fines content of 6.21%. The physical properties of DES pulp were similar to those made by other traditional processes. Meanwhile, approximately 85% of FA and 92% of BTEAC could be reused in the improved chemical recovery process, and the cooking efficiency of recycled DES was largely maintained after 5 times of recycling. Moreover, compared with the kraft process, DES pulping could extract more lignin with high purity and narrow molecular weight distribution. The results proved that this technology could produce high-quality pulp and lignin by-products simultaneously with less energy and chemical consumption. [ABSTRACT FROM AUTHOR]

Thermal drying makes cellulosic fibers shrink, resulting in pore collapse and degraded fiber performance. However, in this work, the pores of cellulose fibers expanded in the later stage of low-temperature thermal drying by regulating the fiber stacked structure before drying, which was called "low-temperature pore expansion effects". The results showed a high content of lignin was required because there were no low-temperature pore expansion effects during the drying process of low lignin-containing cellulosic fibers. Three-dimensional fiber stacked structure was also necessary because cellulose fiber materials with two-dimensional stacked structure, such as paper, had no pore expansion effects. The pore expansion effects first strengthened and then weakened with increasing temperature, and the optimum temperature was 60 °C. According to the results, the pore expansion effects included the pore shrinkage period and pore expansion period. Finally, a possible lignin-cellulose phase separation mechanism was proposed to explain this phenomenon. This work reveals the special ultrastructural transformation of cellulosic fibers under low-temperature drying, providing a reference for precise regulation of the properties of dried fibers. [ABSTRACT FROM AUTHOR]

The charge plays an important role in cellulose nanocrystal (CNC) self-assembly to form liquid crystal structures, which has rarely been systematically explored. In this work, a novel technique combining atomic force microscopy force and atomistic molecular dynamics simulations was addressed for the first time to systematically investigate the differences in the CNC self-assembly caused by external positive and negative charges at the microscopic level, wherein sodium polyacrylate (PAAS) and chitosan oligosaccharides (COS) were used as external positive and negative charge additives, respectively. The results show that although the two additives both make the color of CNC films shift blue and eventually disappear, their regulatory mechanisms are, respectively, related to the extrusion of CNC particles by PAAS and the reduction in CNC surface charge by COS. The two effects both decreased the spacing between CNC particles and further increased the cross angle of CNC stacking arrangement, which finally led to the color variations. Moreover, the disappearance of color was proved to be due to the kinetic arrest of CNC suspensions before forming chiral nematic structure with the addition of PAAS and COS. This work provides an updated theoretical basis for the detailed disclosure of the CNC self-assembly mechanism. [ABSTRACT FROM AUTHOR]

In view of great difficulties in the exploration of Permian shale gas under complex geological conditions in Xuancheng Area, Lower Yangtze Block, an effective shale gas exploration method under complex geological conditions is explored by applying a joint exploration with high-accuracy gravity prospecting, high-precision magnetic method and complex resistivity method (CR method) based on rock property testing. The study shows that The shale of Gufeng Formation in Xuancheng Area is characterized by " low magnetic intensity, low density, medium low resistivity and high polarization", the carbonaceous siliceous shale characterized by low resistivity and high polarization, and the intrusive rock (granite porphyry) that mainly affects Gufeng Formation characterized by "low magnetic intensity, low density, low resistivity and low polarization". In the shale gas exploration at Gufeng Formation, Weidun Belt, Xuancheng Area, high-accuracy gravity prospecting and high-precision magnetic method are applied to identify the areas with low magnetic intensity and low gravity and to deduce the distribution of rock mass. Then, CR profile is arranged in the area where magmatic rock is not developed, and wells are drilled for verification at the locations with low resistivity (less than 1 000.00 Ω·m) and high polarisation (more than 4.00%). A total of 50.89 m thick carbonaceous siliceous shale and siliceous mudstone of Gufeng Formation are drilled, achieving excellent application effect. This study provides an important guide to the identification of organic-rich shale formations and the selection of shale gas "sweet spot" in Xuancheng Area and even in the area with complex geological conditions in Lower Yangtze Block. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most lethal primary tumor in the human brain and lacks favorable treatment options. Sex differences in the outcome of GBM are broadly acknowledged, but the underlying molecular mechanisms remain largely unknown. To identify the sex‐dependent critical genes in the progression of GBM, raw data from several microarray datasets with the same array platform were downloaded from the Gene Expression Omnibus (GEO) database. These datasets included tumorous and normal tissue from patients with GBM and crucial sex features. Then, the differentially expressed genes (DEGs) in female and male tumors were identified via bioinformatics analysis, respectively. Functional signatures of the identified DEGs were further annotated by Gene Ontology (GO) and pathway enrichment analyses. Venn diagram and functional protein–protein interaction (PPI) network analyses were performed to screen out the sex‐specific DEGs. Survival analysis of patients with differences in the expression level of selected genes was then carried out using the data from The Cancer Genome Atlas (TCGA). Here, we showed that ECT2, AURKA, TYMS, CDK1, NCAPH, CENPU, OIP5, KIF14, ASPM, FBXO5, SGOL2, CASC5, SHCBP1, FN1, LOX, IGFBP3, CSPG4, and CD44 were enriched in female tumor samples, whereas TNFSF13B, CXCL10, CXCL8, CXCR4, TLR2, CCL2, and FCGR2A were enriched in male tumor samples. Among these key genes, interestingly, ECT2 was associated with increased an survival rate for female patients, whileTNFSF13B could be regarded as a potential marker of poor prognosis in male patients. These results suggested that sex differences in patients may be attributed to the heterogeneous gene activity, which might influence the oncogenesis and the outcomes of GBM. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system (CNS). Anxiety and depression are the most common psychiatric comorbidities of MS, which seriously affect patients' quality of life, treatment compliance, and prognosis. However, current treatments for anxiety and depression in MS show low therapeutic efficacy and significant side effects. In the present study, we explored the therapeutic effects of a novel low-toxic anti-inflammatory drug, nanoparticulate magnesium hydride (MgH2), on mood disorders of MS. We observed that anxiety/depression-like behaviors in experimental autoimmune encephalomyelitis (EAE) mice were alleviated by MgH2 treatment. In addition, disease severity and inflammatory demyelination were also diminished. Furthermore, we confirmed the suppressive effect of MgH2 on depression in the acute restraint stress model. Mechanistically, MgH2 may play a therapeutic role by promoting microglial M2 polarization, inhibiting microglial M1 polarization, and reducing oxidative stress and mitochondrial damage. Therefore, nanoparticulate MgH2 may be a promising therapeutic drug for psychiatric comorbidities of MS. [ABSTRACT FROM AUTHOR]

In this work, a short-term thermal drying procedure of cellulosic fibers was designed to present pore expansion and increase via lignin-cellulose phase separation. The applicability of this procedure was studied by using four never-dried cellulosic fibers with different lignin contents and tree species (poplar, eucalyptus, bamboo) as raw materials. This procedure significantly improved the properties of high lignin containing fibers, especially pore parameters and water retention capacity. When heated at 150 °C, the increased yields of fiber properties reached 38% (specific surface area), 26.8% (pore volume), 30.5% (average pore size), and 29.4% (water retention value), respectively. Based on its most critical change, this phenomenon was called "thermal drying-induced pore expansion effects". Key factors for pore expansion effects were temperature, time, lignin content, and the stacked structure (i.e., fiber arrangement structure). Pore expansion effects could be used to enhance pore related applications, such as lignocellulosic enzymatic hydrolysis and papermaking. Pore expansion effects under heating at 105 °C for 10 min increased enzymatic digestibility at 6 h by 11%. After the same treatment, the water absorption and bursting index of papers made of the treated fibers were increased by 9.09% and 40%, respectively. The pore expansion effect proposed in this study expands the drying research of cellulosic fibers and provides a reference for using drying to enhance biomass conversion and improve the properties of cellulose materials. [ABSTRACT FROM AUTHOR]

In recent years, distributed energy has been gradually applied in residential electricity consumption, and smart devices have been rapidly developed among residential households. This paper establishes a model of optimal scheduling system for building load, taking into account the needs of grid side and customer side, and takes the total cost of electricity consumption and total deviation of electricity consumption of building residents as the optimization objectives. Then, a multi-objective equilibrium optimizer algorithm integrated competition mechanism (CMOEO) is proposed to solve the multi-objective optimization scheduling problem of building loads with multi-decision variables. The algorithm is improved from the equilibrium optimizer algorithm by introducing the competition mechanism, replacing the original exploration and exploitation constant coefficients with dynamic factors and integrating differential evolution. Through the comparison experiments of different algorithms and the different capacity of photovoltaic energy storage system (PESS), the results show that the CMOEO has fast convergence speed, strong merit-seeking ability and better population diversity. In addition, the configuration of PESS is conducive to reducing the cost of electricity for building residents and playing the role of peak-shaving and valley-filling. [ABSTRACT FROM AUTHOR]

According to the natural language perspective, UGC has been significantly used for the screening of key nodes in knowledge discovery and strategic investment. This article presents a new research framework that is proposed for the decomposition of UGC knowledge feature extraction into topic recognition and language analysis, mainly. For visual analysis of associated topics, the LDAvis approach is utilized. Then, risk features of UGC knowledge are assigned according to language attribution. Based on previous studies, the risk attribute lexicon is further updated by judging semantic distance through word vectors. This research uses platform data and individual stock data as samples for subject recognition and knowledge feature extraction. A regression model is constructed based on the panel data after natural language processing to verify the feedback effect of the market at strategic risk measurement. It can be found from the conclusion that the change in market behavior is regular and correlates with the change in the UGC risk degree of individual stocks. The purpose of this paper is to examine the value of UGC in investment decision-making from the perspective of knowledge discovery. The research content can provide a reference for data mining, fintech, strategic risk monitoring, and other related works. [ABSTRACT FROM AUTHOR]

Nanocellulose, a unique and promising nanosized cellulose fibers extracted from renewable biomass, has gained much attention from both the scientific and industrial communities due to abundant resources, good mechanical properties, distinct surface chemistry, and biological properties. Thus, nanocellulose is a appealing biomaterial for exciting applications, including super absorbent materials, electronic components, energy devices, and reinforcements. Cellulose nanocrystal (CNC), cellulose nanofibril (CNF), and bacterial cellulose (BC) are the three main kinds of typical nanocellulose from different routes, thus the comprehensive comparison of CNC, CNF, and BC is highly desirable. In order to better understand their special characteristics, we have described detailedly of CNC, CNF (including TEMPO oxidized CNF and mechanically ground CNF), and BC in current work. Meanwhile, this study systematically compared their preparation method, morphologies, chemical structure, surface chemistry, degree of polymerization, thermal behavior, mechanical property, and so on, all these are good for understanding the structure–property–function relationships of nanocellulose. The systematic comparative study can help to develop the criteria for selecting proper nanocellulose as biobased nanomaterials for high value-added applications. We believe that these detailed information presented here have the potential to achieve true sustainable, economic, and tailored production of nanocellulose at large scale, thus contributing to the advancement of biobased nanocellulose. [ABSTRACT FROM AUTHOR]

This work investigated the relationship between freeze-drying and supercritical drying of cellulosic fibers with different moisture contents based on pore and crystallinity measurements. The results showed that freeze-drying reduced the specific surface area and pore volume of cellulosic fibers by 20–160-fold, compared to supercritical drying. At the same time, freeze-dried fibers had a higher crystallinity index and crystal size than supercritically dried fibers. Freeze-drying also significantly changed the nitrogen adsorption–desorption isotherm and pore size distribution of cellulosic fibers. However, most importantly, freeze-dried fibers had linear positive correlations with supercritically dried fibers in terms of pore parameters and crystallinity, indicating that freeze-dried samples retained the trends and qualitative relationships of supercritically dried fibers. Therefore, freeze-drying can be used as the pretreatment procedure for pore and crystallinity measurements of cellulosic fibers from poplar and eucalyptus when comparing the effects of thermal drying. This work also deepens the understanding of the drying of cellulosic fibers. [ABSTRACT FROM AUTHOR]

The exacerbation of progressive multiple sclerosis (MS) is closely associated with obstruction of the differentiation of oligodendrocyte progenitor cells (OPCs). To discover novel therapeutic compounds for enhancing remyelination by endogenous OPCs, we screened for myelin basic protein expression using cultured rat OPCs and a library of small-molecule compounds. One of the most effective drugs was pinocembrin, which remarkably promoted OPC differentiation and maturation without affecting cell proliferation and survival. Based on these in vitro effects, we further assessed the therapeutic effects of pinocembrin in animal models of demyelinating diseases. We demonstrated that pinocembrin significantly ameliorated the progression of experimental autoimmune encephalomyelitis (EAE) and enhanced the repair of demyelination in lysolectin-induced lesions. Further studies indicated that pinocembrin increased the phosphorylation level of mammalian target of rapamycin (mTOR). Taken together, our results demonstrated that pinocembrin promotes OPC differentiation and remyelination through the phosphorylated mTOR pathway, and suggest a novel therapeutic prospect for this natural flavonoid product in treating demyelinating diseases. [ABSTRACT FROM AUTHOR]

The Shikou gold deposit, a newly discovered gold deposit with prospect potential, is tectonically located in Qinzhou-Hangzhou metallogenic belt. In order to further expand the prospecting results, this paper analysis the primary halo characteristics of orebody No. III-2, and discusses the prospecting potential of the Shikou gold deposit in combination of the results of soil geochemical measurement,. The research results show that; (1) As, Ag and Sb are strongly related to Au which is the main metallogenic element. F is a typical indicator element in this region, (2) the mineralization of orebody No. III-2 might have experienced multiple-stage superposition, and the rear halo elements appears in the front of axial zoning sequence of the primary dispersion halo, which indicate certain metallogenic potential in deep area. The authors hold that there might be a further ore-prospecting space along the strike of the ore section - and in the deep of orebody No. III-2. [ABSTRACT FROM AUTHOR]

Having the advantages of a higher yield, lower cost and less environmental impact, lignin-containing cellulose nanofibrils (LCNFs) obtained by mechanically fibrillating unbleached pulps have been demonstrated to be a promising alternative to high-purity nanocellulose. In this study, the structural changes after four drying methods containing freeze-drying (FD), oven-drying (OD), centrifugal followed by vacuum-drying (CVD), and evaporation followed by vacuum-drying (EVD), and efficient reuse of LCNFs were extensively explored. It was found that the structural characteristics of LCNFs after drying were maintained by freeze drying with high lignin contents where the aggregation of fibrils was alleviated by lignin. The freeze-dried LCNFs were further redispersed by homogenizer in water, which exhibited excellent dispersion characteristics. In addition, the redispersed LCNFs were further assembled into PVA films to fabricate high-strength composites. The results showed that when the addition of redispersed LCNFs was up to 16.9%, the tensile strength and elongation at break of the as-prepared composite film increased by 325.2% and 335.2%, respectively. This study demonstrated a more sustainable approach to utilize LCNFs to produce biomass-based composite films than those of CNF-based composite films. [ABSTRACT FROM AUTHOR]

This study aims to investigate the relationship between mechanical fibrillation, morphological properties, and rheological behavior of cellulosic fiber. Three types of cellulosic fibers were obtained by adjusting mechanical fibrillation, namely squashed cellulose, incompletely nanofibrillated cellulose, and completely nanofibrillated cellulose, respectively. The squashed cellulose with large size and small aspect ratio had low entanglement capacity, thus forming a weak fiber network. The corresponding suspension exhibited low viscosity, weak elastic behavior, small yield stress, and low dynamic stability. An obviously increasing aspect ratio and entanglement capacity were observed with increasing mechanical fibrillation, resulting in entangled fiber network structure. Hence, the cellulosic fiber suspension obtained by more mechanical fibrillation exhibited higher viscosity, stronger gel-like behavior, and bigger yield stress. Moreover, the extremely entangled fiber network structure has better anti-deformation capacity and recovery capacity. We revealed the fundamental insights into the relationship between morphologies and rheological properties of cellulosic fiber, paving the way for designing cellulose-based materials. [ABSTRACT FROM AUTHOR]

The production of sustainable bioaerogel by using renewable biomass via eco‐friendly techniques is a meaningful research topic. This study reports a facile bottom‐up green strategy to construct dimensionally stable bioaerogel derived from bacterial cellulose (BC). Taking advantages of the natural hierarchical and interconnected network structure of BC, the preparation of bioaerogel comprises directional freezing, followed by freeze‐drying approach. Aside from the multifunctional characteristics such as high porosity, low density, and large specific surface area, the resultant BC bioaerogels show superhydrophilic property, excellent water absorption, and swelling characteristics. In addition, the extremely compressed bioaerogel film exhibits flexibility and good mechanical properties. And the BC bioaerogels display a low coefficient of thermal conductivity (25.8 mW m−1 K−1). Moreover, the BC bioaerogels reveal excellent sound absorption at board frequencies from 200 to 6000 Hz with a maximum sound‐absorption coefficient of 0.97. The BC bioaerogel is further used as the green, sustainable, and degradable cigarette filter tip, exhibiting good adsorption effect for the smoke main components. In summary, this study provides a feasible solution to rationally construct lightweight, high porous, heat‐insulating, and highly efficient sound‐adsorption BC bioaerogel, which has potential applications in the future as green advanced functional materials. [ABSTRACT FROM AUTHOR]

The aim of this work is to study and compare the morphology and rheology of cellulose nanofibrils (CNFs) from bleached softwood kraft pulp by several mechanical treatment methods. Three different kinds of CNFs were prepared in this work: (i) ones produced by PFI milling and microfluidic homogenization (RM-CNFs), (ii) ones produced by grinding and microfluidic homogenization (GM-CNFs), and (iii) ones produced by ball milling and ultrasonication (BU-CNFs). RM-CNFs had a high aspect ratio and the highest viscosity, storage modulus, and loss modulus. GM-CNFs had homogeneous size distributions, but low aspect ratio due to severe shearing of narrower orifice of chamber in microfluidic homogenization process. For BU-CNFs, the size distributions were heterogeneous, but they had a high aspect ratio. The three kinds of CNFs all had a lower crystallinity index than BSKP, and the degree of polymerization decreased with the increase of treatment intensity. Results of rheology measurements showed that those CNFs had a high degree of fibrillation and had a wider linear viscoelastic region in oscillatory strain measurements. Also the CNFs with high aspect ratio had a high viscosity and modulus. Additional treatments did not always increase the viscosity and modulus due to too severe treatments, which could cause the decrease of aspect ratio of CNFs. The RM-CNFs had a high viscosity and modulus, which means they are suitable in applications of rheology control. [ABSTRACT FROM AUTHOR]

We describe an effective method to create nanocomposites of silver nanoparticles that were stabilized by cellulose nanofibrils (CNF-AgNPs) that were then mixed with a starch matrix. The incorporation of CNF-AgNPs nanocomposites significantly enhanced the mechanical and antibacterial properties of hybrid films. The starch-based films with only 5.0 wt% CNF-AgNPs content exhibited superior mechanical properties in which the Young's modulus increased from 80.3 to 381.5 MPa and tensile strength increased from 6.06 to 9.96 MPa at 50% RH. Taking advantage of the denser microstructure and strong interfibrillar networks, the nanocomposite film can resist more external tensile forces and show excellent barrier property and thermostability. Moreover, antibacterial analysis indicated that CNF-AgNPs/starch nanocomposite films exhibited strong bactericidal effects against representative both Escherichia coli and Staphylococcus aureus. The cell viability of 87.71% and clear morphologies of live cells implied good biocompatibility of nanocomposite films. The demonstrated characteristics of CNF-AgNPs/starch nanocomposite film verified its suitability as a sustainable material for food packaging. [ABSTRACT FROM AUTHOR]

Plant fiber isolated cellulose nanofibers (CNFs) are the materials with excellent mechanical properties. However, application of CNFs in polymer reinforcement is normally unsatisfactory due to its intertwined size distribution. Efforts to produce uniform sized CNFs have yet to be studied. In present work, spiral microchannel was used to fractionate CNFs based on the balance between inertial lift force (FL) and Dean drag force (FD) exerted on CNFs. The results showed that the smaller length of CNFs equilibrated near the inner microchannel while the larger length of CNFs occupied the equilibrium position away from the inner wall. With the increase of flowrates from 50 to 220 μL/min, fractionation efficiency between inner and middle outlet (EIM) of spiral microchannel A with larger radius curvature (R) from 5 to 15 mm increased from 0 to 75.4%. However, stronger Dean flow attributing to decrease of R (3 mm to 10 mm) of single spiral microchannel B enabled satisfactory fractionation efficiency of 70.9% at flowrate of 90 μL/min. Moreover, the fractionation efficiency of double spiral microchannel with twice as length as microchannel A and three times as length as microchannel B was lower than that of single spiral microchannel at flowrate lower than 90 μL/min. Furthermore, this study exhibited a versatile and simple method for CNFs fractionation with high fractionation efficiency. [ABSTRACT FROM AUTHOR]

The microstructure and properties of lignocellulosic fibers usually change during the drying process due to the hornification of fibers. The water retention ability of fibers is an effective way to reflect the degree of fiber hornification. In this study, the effects of lignin content on the microstructural properties of dried-redispersed LCNFs (DLCNFs) were extensively explored. The results showed that the high content of lignin could maintain the microstructural integrity of DLCNFs. The water retention value and hornification degree of high lignin content DLCNFs (22.1%, w/w) were 289.8% and 6.9%, which were much lower than those of low lignin content (6.2%, w/w) DLCNFs. This was probably because that the crosslinking between lignin and carbohydrate effectively prevented the hydrogen bonding formation in the interior-fibers and exterior-fibers, and reduced the irreversible hornicficatoin of LCNFs. This study will be beneficial for the development of the LCNF drying mechanism. [ABSTRACT FROM AUTHOR]

Industrial emissions and oil spills as worldwide challenges have induced severe pollution and threatened the ecological environment. Conventionally, superhydrophobic surfaces show underwater lipophilicity, whereas superhydrophilic surfaces exhibit underwater oleophobicity. However, the intrinsic characteristics of these materials limit their practical applications for dealing with industrial oily wastewater. Here, from a chemical point of view, a lignocellulosic fiber surface with superwetting characteristics was successfully fabricated by the strategically adjusted condensation reaction of melamine and formaldehyde, making it underoil superhydrophobic and underwater superoleophobic. The formation of the dual superlyophobic surface in oil/water systems was related to the surface topography and the essential chemistry of the modified lignocellulosic fibers. After being pre-wetted by water, the dual superlyophobic melamine formaldehyde lignocellulosic (DSMFL) fibers were able to separate a light-oil/water mixture by gravity filtration. Simultaneously, the DSMFL fibers were sufficient to separate a heavy-oil/water mixture when they were pre-wetted by a heavy oil under a gravity-driven mechanism. In addition, the DSMFL fibers still showed excellent dual superlyophobicity along with robust chemical stability and had high separation efficiencies for dichloroethane (DCE)/water or kerosene/water mixtures after 50 separation cycles. The effective absorption of the light oil on the upper layer of the aqueous phase exceeded 1000%. Finally, the DSMFL fibers could be degraded into a nitrogen source for plant growth. [ABSTRACT FROM AUTHOR]

Lipstick is a kind of popular cosmetic, which can give the lip a beautiful color and improve its appearance. The problem is that dye molecules would be in contact with the skin, whereas the lipstick made with dyed CNCs (CNC-lipstick) would reduce the contact. Herein, we demonstrated that the deficiency of color migration can be overcome by using the cellulose nanocrystal (CNC) dye to replace conventional dye in the lipstick substrates. The lipstick containing CNC dye (CNC-lipstick) could effectively inhibit the color migration and was easily erased as compared to ordinary lipsticks. The color change on the scoured skin was as high as ΔE* = 30.4 after using red ordinary dye-lipstick for 8 h, and red residue was clearly observed in the texture of the skin. Further cleaned with makeup remover, the color change on the scoured skin was ΔE* = 6.4. Notably, the color change of CNC-lipstick was ΔE* < 5, and only a small amount of red residue could be observed in the texture of the skin. The reduction of color migration from the lipstick to the skin was probably due to the fact that the dye absorbed by the CNC, which slowed down the diffusion rate of dye molecules. Our work paves the way for using CNC dye for inhibiting color migration in the lipstick application. Cellulose nanocrystals were applied to prepare the color easy-cleaned lipstick. [ABSTRACT FROM AUTHOR]

Lignin is a low-cost and sustainable alternative precursor for manufacturing carbon fibers (CFs). However, the properties of lignin-based CFs are inferior due to the heterogeneity and complex three-dimensional structure of lignin. In this work, a facile stepwise fractionation extraction method is devised to extract lignin. This stepwise fractionation extraction method effectively removes the small molecular branching structure of lignin, thus obtaining fractionated lignin with a high molecular weight, narrow polydispersity index, and linear structure. Based on the results of XRD and Raman spectroscopy, the high molecular weight, narrow polydispersity index, and linear structure are conducive to improving the graphitization degree of CFs. Compared with the lignin-based CFs from original lignin, the tensile strength and Young's modulus of the lignin-based CFs from the fractionated lignin increase significantly, extraordinarily approaching those of PAN-based CFs. This facile stepwise fractionation extraction method for lignin is promising for the industrial production of high performance lignin-based CFs. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces have received increasing attention in a broad range of important fields including oily wastewater treatment and oil collection in spills accidents. However, the preparation of such superhydrophobic surfaces has been proven to be energy-intensive and these surfaces are non-degradable. Herein, a naturally abundant fibrous substrate (i.e., lignocellulosic fibers and cotton fabric), mainly composed of cellulose, combining inexpensive bulk chemicals (melamine, formaldehyde, and octadecylamine) was cleverly designed and strategically exploited for the low-cost, easy scale-up, and eco-friendly superhydrophobic surface. These superhydrophobic surfaces can be used to clean different forms of oil-contaminations, including floating light-oil and sedimentary heavy-oil (with an efficiency above 700 wt% for various oils). This study showed that the superhydrophobic surfaces created via a scalable and green water solvent-assisted condensation reaction can achieve high water repellency both in air and in oil, and exhibited a single efficient avenue for gravity-driven active filtration of oil. The superhydrophobicity of the octadecylamine–melamine–formaldehyde (OMF) lignocellulosic fibers remained unperturbed even after long-term exposure to UV radiation (at both 254 nm and 365 nm) for 168 h. The OMF lignocellulosic fibers showed good antifouling properties and maintained high separation efficiency (＞95%) as well as a high water contact angle (＞150°) after being repeatedly used for 70 cycles. Furthermore, this strategy exhibited good versatility for superhydrophobic cotton fabrics with high contact angles (＞160°) and high water/oil separation efficiency (96%). [ABSTRACT FROM AUTHOR]

Correction for 'Fireproof ultrastrong all-natural cellulose nanofiber/montmorillonite-supported MXene nanocomposites with electromagnetic interference shielding and thermal management multifunctional applications' by Rui Cheng et al., J. Mater. Chem. A, 2023, 11, 18323–18335, https://doi.org/10.1039/D3TA03798C. [ABSTRACT FROM AUTHOR]

ABSTRACT In order to optimize the use of residues of enzymatic hydrolysis of corn stalk (REHCS) and explore the low-cost and sustainable raw material substitute for carbon fibers, three types of lignin samples were extracted from REHCS by various extraction methods, and then they were converted into carbon fibers (CFs) by electrospinning, thermostabilization, and carbonization under the same process conditions. The microstructure and mechanical properties of the three types of carbonized fibers were different. The CFs from the ethanol organosolv lignin were actually smooth and brittle carbon films. The CFs from the formic acid/acetic acid organosolv lignin had microscopic pores, causing poor mechanical properties. Comparatively, the CFs from the alkaline lignin demonstrated preferable microstructure and mechanical properties. The reasons for the differences were analyzed by characterizing the lignin samples, precursor fibers, and resultant CFs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45580. [ABSTRACT FROM AUTHOR]

Addition of precipitated calcium carbonate (PCC) to cellulosic products can reduce production costs and modify their physical properties. This study investigated the effects of adding PCC on the properties of reconstituted tobacco sheet (RTS), a cellulosic product. Scanning electron microscopy (SEM) analysis showed that adding PCC to the coating could modify the surface microstructure of RTS. With increasing PCC addition, the strength and tar release per cigarette of RTS decreased. However, the filling capacity, bulk, and CO release content in the mainstream smoke reached optimal values when the proportion of PCC in the coating was 8%. Thermogravimetry (TG) and differential thermogravimetry (DTG) analysis indicated that the main thermal pyrolysis stage occurred in the range of 200-400 °C, similar to cellulosic components. The Coats-Redfern equation was used to analyze the thermal pyrolysis mechanism. The fitting results showed that, in the range of 200-280 °C, the best fit model for RTS with 4 or 8% PCC was diffusion-controlled reaction (D1) with fitting correlation coefficient ( r ) of 0.9630 and 0.9576, respectively. Meanwhile, in the range of 280-400 °C, the most reliable fitting model for RTS with 4% PCC was chemical reaction (F2) with r = 0.9681. One reaction model could not describe the thermal pyrolysis of RTS with 12% PCC in the main decomposition stage. The thermal kinetic parameters suggested that addition of PCC to RTS coatings could modify the thermal pyrolysis mechanism, but did not change the peak temperatures in the main thermal decomposition stage. This study demonstrates that addition of PCC to RTS coating is a promising method to improve its quality. [ABSTRACT FROM AUTHOR]

In this study, the removal of tungsten from electroplating wastewater by adsorption on sepiolite has been investigated. To improve its performance, the natural sepiolite, was treated using H2SO4, followed by a heat treatment. The results obtained from the adsorption experiments showed that the acid- and heat-treated sepiolite had much higher adsorption for tungsten compared to the untreated (natural) sepiolite. The pH and temperature were important parameters in the adsorption process: the tungsten adsorption onto the acid- and heat-treated sepiolite increased at a lower pH and higher temperature, and the maximum adsorption capacity of 48.3 mg/g was obtained at pH 4.0, 55°C, initial concentration of tungsten of 300 mg/L, and the sepiolite to liquid ratio of 0.5 g/100 mL. The acid- and heat-treated sepiolite was applied to electroplating industrial wastewater containing 265 mg/L tungsten, under the conditions of pH ≤ 6, 25–55°C, more than 98% of tungsten was removed. It was concluded that the acid- and heat-treated sepiolite is a potential adsorbent that can be commercially used to remove the residual tungsten in industrial wastewater. [ABSTRACT FROM PUBLISHER]

ABSTRACT Heat-sealing properties are necessary for packaging materials. Soy protein isolate/polyvinyl alcohol (SPI/PVA) blend film is a biodegradable potential packaging material. We analyzed the effects of PVA content (0-20%), glycerol content (1-3%), and sealing temperature (180-230°C) on the heat-sealing properties of SPI/PVA blend film. Results showed that SPI/PVA film obtained the desired sealing properties when the PVA content exceeded 15%. The sealing strength increased with the PVA content, reaching a maximum upon blending with 20% PVA and 1% glycerol at 220°C. The temperature at sealing strength was approximately twice that at 180°C. However, glycerol migrated to the surface and hindered the entanglement of macromolecular chains in the sealing interface, thereby resulting in reduction of seal strength. Glycerol vaporization at 204°C led to aesthetically unacceptable blistering in the sealing area. Therefore, the optimum sealing temperature of the blended film was ∼200°C. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40308. [ABSTRACT FROM AUTHOR]

Reversible light-responsive nanogels were constructed from an amphiphilic spiropyrane-modified pullulan (SpP). The polymer was synthesized by modifying a biodegradable pullulan with carboxyl-containing spiropyrane (Sp) molecules. The SpP structure was confirmed by the appearance of a carbonyl signal in the FT-IR and 1H NMR spectra. The nanogels can be controlled by photostimulation, which results in the reversible structural transformation of the hydrophobic Sp to the hydrophilic merocyanine. The physical properties of the nanogels were confirmed to change dramatically after being irradiated with different wavelengths of light. Drug delivery tests showed that the model drug pyrene was completely captured by the nanogels and then released from the SpP nanogels in a light-dependent manner. This study provides an alternative approach to constructing light-responsive nanocarriers with excellent biocompatibility for drug uptake and release. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40288. [ABSTRACT FROM AUTHOR]

Accurate determination of the thermal properties of cellulose is of particular significance in studying the mechanism of cellulosic cigarette paper combustion. This paper probes into the influence of four kinds of potassium carboxylates on the thermal degradation kinetics and the heat properties of cigarette paper through simultaneous thermogravimetric analysis (TGA) coupled with differential scanning calorimetry (DSC) measurement under air atmosphere. Reduced mass loss and mass loss rate, and increased solid residue for samples containing four potassium salts implied that potassium carboxylates may retard the formation of levoglucosan and volatiles by inhibiting the depolymerization reaction and simultaneously accelerate char formation by catalyzing the dehydration reaction. Kinetic parameters were analyzed based on three non-isothermal models available in literature. The results indicated that three modeling methods exhibit good consistency. A global activation energy range of 106–155 kJ mol −1 was proposed for cigarette paper with potassium carboxylates. The four potassium salts studied considerably reduced the activation energy in the following descending order: potassium 1,2,3,4-butane tetracarboxylate (PBTCA) > citrate > gluconate > ascorbate. The heat properties of cigarette paper were also determined by integrating the DSC curves. The results demonstrated that both cellulose degradation and char oxidation have strong exothermic peaks. Cigarette paper samples with potassium salts have lower exothermic cellulose degradation process and higher exothermic char oxidation process, which were further confirmed by greater differences as the amounts of salt citrate or PBTCA increased. [ABSTRACT FROM AUTHOR]

ABSTRACT A study using coagulation-flocculation method for the treatment of papermaking-reconstituted tobacco slice wastewater had been carried out. Polyaluminum chloride (PAC) and polyferric sulfate (PFS) as coagulants, and four kinds of polyacrylamides (PAMs) as flocculants, were employed during the coagulation-flocculation process. The effects of three factors, that is, the dosage of coagulants, the dosage of flocculants and pH on the treatment efficiency of the process were evaluated. The results showed that the efficiencies of PAC and PFS on the reduction of COD, ammonia nitrogen (NH3-N) and total suspended solids (TSS) in the treated effluents were equivalent; however, the efficiency of PAC on the color reduction was much higher than that of PFS. In the presence of PAC, a cationic polyacrylamide with very high molecular weight and low charge density (i.e., PAM4) was found to give the highest coagulation-flocculation efficiency. At the optimal conditions, that is, pH of 6.5, PAC dosage of 500 mg/L, and PAM4 dosage of 5 mg/L, the reductions of COD, NH3-N, color, and TSS in the process were found to be 70.8, 84.8, 72.3, and 98.5%, respectively. The study also showed that the PAC-PAM4 scheme can remove the most of aluminum from the raw water. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1092-1097, 2013 [ABSTRACT FROM AUTHOR]

Stock movement prediction is important in the financial world because investors want to observe trends in stock prices before making investment decisions. However, given the non-linear non-stationary financial time series characteristics of stock prices, this remains an extremely challenging task. A wavelet is a mathematical function used to divide a given function or continuous-time signal into different scale components. Wavelet analysis has good time-frequency local characteristics and good zooming capability for non-stationary random signals. However, the application of the wavelet theory is generally limited to a small scale. The neural networks method is a powerful tool to deal with large-scale problems. Therefore, the combination of neural networks and wavelet analysis becomes more applicable for stock behavior prediction. To rebuild the signals in multiple scales, and filter the measurement noise, a forecasting model based on a stock price time series was provided, employing multiresolution analysis (MRA). Then, the deep learning in the neural network method was used to train and test the empirical data. To explain the fundamental concepts, a conceptual analysis of similar algorithms was performed. The data set for the experiment was chosen to capture a wide range of stock movements from 1 January 2009 to 31 December 2017. Comparison analyses between the algorithms and industries were conducted to show that the method is stable and reliable. This study focused on medium-term stock predictions to predict future stock behavior over 11 days of horizons. Our test results showed a 75% hit rate, on average, for all industries, in terms of US stocks on FORTUNE Global 500. We confirmed the effectiveness of our model and method based on the findings of the empirical research. This study's primary contribution is to demonstrate the reconstruction model of the stock time series and to perform recurrent neural networks using the deep learning method. Our findings fill an academic research gap, by demonstrating that deep learning can be used to predict stock movement. [ABSTRACT FROM AUTHOR]