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As a new type of biomass-based molecular material, nanocrystalline cellulose (NCC) has become a research hotspot in many fields. In present work, a novel microfluidic technology was employed to produce NCC from microcrystalline cellulose (MCC) via sulfuric acid hydrolysis. The microfluidic chip was designed and made with complete load-bearing reaction according to flow characteristics. A closed reaction environment and fully automated operations can ensure the safety of experimenters. NCC (MN-60) with high yield and uniformity was obtained via acid hydrolysis in microfluidic system by 60 % sulfuric acid solution at 35 °C for 40 min. The characteristics of MN-60 and conventional method NCC (N-60) under the same reaction conditions were compared. It was found that the yield of MN-60 reached 48.13%, while it was only 17.30 % in the absence of microfluidic chip. Although the results showed that MN-60 and N-60 exhibited similar rod-like structures, the size distribution of MN-60 was narrower than that of N-60. Furthermore, the width, length, and height of MN-60 were 15±5 nm, 150±75 nm, and 5±2 nm, respectively. The main functional groups and crystal forms of MN-60 were similar to MCC, but the crystallization index of MN-60 was higher than MCC. In conclusion, microfluidic technology could realize the preparation of high-yield and uniform NCC.

The development of structure/function integrated materials is an important trend in military field. Herein, a hierarchical structure was introduced on carbon fiber surface via the successively grafting of polyacrylic acid (PAA) layer and Fe3O4 nanoparticles. It is found that this hierarchical structure could simultaneously improve the composites interfacial strength (30.5%) and toughness (82.6%), due to the mechanical interlocking by Fe3O4 and polarity matching by PAA layer. Moreover, for fiber's microwave absorption (MA) performance, the introduced magnetic Fe3O4 nanoparticles facilitate the impedance matching and magnetic loss, and large number of dipoles from PAA provide polarization loss for microwave dissipation, and finally lead to enhanced MA properties with strong absorption (−40.6 dB) and a wide effective bandwidth (6.13 GHz). In all, the present study offers a facile strategy for the preparation of structural/microwave-absorbing integrated carbon fiber, and could further provide guidance for other carbon fiber-based multifunctional materials.

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.

The complex [Pb(phen)(4-NB)(CH3COO)] of lead(II) was prepared and characterized by means of elemental analysis, FT-IR, and single crystal X-ray analysis, where phen = 1,10-phenanthroline, 4-NB = 4-nitrobenzoate. The single crystal X-ray analysis indicates that the complex is a monomeric species, including two carboxylate ligands, and adopts a hemidirected structure. It is further extended by intermolecular C−H⋯O hydrogen bonds, π–π interactions and secondary Pb⋯O interactions to form two-dimensional supramolecular architecture.

The stereochemistry of tetraphenylethene (TPE) derivatives with aggregation induced emission (AIE) characteristics has demonstrated significant value in advanced materials and life sciences. Geometric Z/E-diamino substituted TPE (Z/E-2NH2-TPE) suffers from tautomerization and separation. To resolve this problem, pure geometric Z/E diamino and dichloro dual-substituted TPE (Z/E-2Cl-2NH2-TPE) molecules were designed precisely and separated via common column chromatography by introducing chlorine. Tautomerization would not occur even after being kept at increased temperature (200 °C) for 2 hours or at room temperature for 6 months. The role of chlorine atoms in geometric Z/E-2Cl-2NH2-TPE molecules has been deeply elucidated through theoretical computational chemistry methods and intermolecular interaction. Compared with Z/E-2NH2-TPE molecules, the Frank–Condon excitation, transition state of the tautomerization process, conical intersection, and photoluminescence in the potential energy surface of Z/E-2Cl-2NH2-TPE molecules were similar to those of Z/E-2NH2-TPE molecules. The energy barrier of tautomerization seldom clarified the role of the chlorine atoms while enhanced intermolecular interaction provided by chlorine atoms effectively rigidified the conformation of the tautomerization process. Thereafter, different mechanochromism (MC) photochemical properties were probed in depth, which were induced by structure-dependent molecules’ H/J-aggregation state and reorganization energy. The tautomerization-inhibited Z/E-2Cl-2NH2-TPE molecules with a reactive functional group provided a good template for designing advanced materials.

A photocatalytic protocol for the divergent dearomative functionalization of indole derivatives is reported. Under the irradiation of visible light, either dimerization or reduction occurs selectively by modifying the reaction conditions, leading to the formation of the corresponding cyclobutane-fused polycycles and 2-substituted indolines in good yields with exclusive selectivity.

Electrochemical organic synthesis has attracted increasing attentions as a sustainable and versatile synthetic platform. Quantitative assessment of the electro-organic reactions, including reaction thermodynamics, electro-kinetics, and coupled chemical processes, can lead to effective analytical tool to guide their future design. Herein, we demonstrate that electrochemical parameters such as onset potential, Tafel slope, and effective voltage can be utilized as electro-descriptors for the evaluation of reaction conditions and prediction of reactivities (yields). An "electro-descriptor-diagram" is generated, where reactive and non-reactive conditions/substances show distinct boundary. Successful predictions of reaction outcomes have been demonstrated using electro-descriptor diagram, or from machine learning algorithms with experimentally-derived electro-descriptors. This method represents a promising tool for data-acquisition, reaction prediction, mechanistic investigation, and high-throughput screening for general organic electro-synthesis.

Summary In this study, we developed a pathway to valorize sugarcane bagasse left from sugar production to food-related end products through pulp molding, which represents a sustainable material and clean manufacturing. The sugarcane bagasse from the sugar industry is naturally safe for food-related applications. The produced tableware is fully biodegradable, renewable, and environmentally friendly. We also developed a hybrid fiber strategy that long bamboo fibers were blended with short sugarcane fibers, which formed abundant physical interwinding in the obtained tableware with superior performances as required for food containers, including high tensile strength, superior oil stability, excellent hydrophobicity, and low heavy metal content. Of note, our tableware was mostly biodegraded under natural conditions within 60 days, which is largely shorter than the degradation time for synthetic plastics. Moreover, in comparison with polystyrene production, pulp molding produced much less CO2 emission. The tableware made from biomass thus represents an eco-friendly, low cost, and biodegradable alternative to synthetic plastics for food packaging.

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.

Fluorine-free cellulosic paper was successfully obtained by coating the glassine base paper with eco-friendly cellulosic coating, which was made from dissolving cellulose in 8 wt% NaOH/12 wt% urea aqueous solution. Then the coated paper was severally immersed into CH3COOH, Na2SO4, and H2O solution to coagulate and regenerate. Benefiting from the compact matrix and fully covered surface, the resultant cellulosic paper exhibited favorable barrier properties and mechanical performance. Notably, the paper coagulated with CH3COOH displayed the reduction in water–vapor transmission rate, air permeability, and uptake of organic solvents due to its low porosity (26.8%) and narrow pore size distribution (0.1–0.36 µm). The tensile strength and elongation at break of papers treated by CH3COOH at coating weight of 5 g/m2 were increased by 72.1% and 34.0%, respectively. In summary, the fluorine-free cellulosic paper with high oil and grease resistance is attractive for the development of high-performance materials for food packing applications. Fluorine-free paper was obtained from the glassine base paper coated with eco-friendly, non-fluorinated, and degradable cellulosic coating, then coagulated with CH3COOH, Na2SO4, and H2O solution, respectively. The resultant functional papers displayed enhanced barrier properties (oil, organic solvent, vapor, and gas) and mechanical performance.

Cellulose nanofibril (CNF) is a class of promising and renewable nanocellulosic material due to its unique dimensional characteristics and appealing properties. CNF preparations based on TEMPO pretreatment followed by high-pressure homogenization have been studied intensively, while the high energy consumption and the environmental issues remain challenges to their application. Mechanical refining processes have been commonly applied at the academic and industrial relevant scales for CNF production. In this study, bleached softwood kraft pulp was subjected to high-efficiency wet ball milling (following enzymatic pretreatment) and mechanical grinding to obtain CNF. The effects of ball milling time, grinding gap, and grinding passes on structure and properties of CNF were evaluated. Scanning electron microscopy images confirmed that the diameter of CNF was decreased with the increment of ball milling time and number of grinding passes. The results indicated that ball milling time, grinding gap, and grinding passes were important to increase the dispersity of CNF suspensions. The degree of polymerization and crystallinity index of CNF decreased with increasing ball milling time and grinding passes.

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.

Efficient selective separation of oils or organic pollutants from water is important for ecological, environmental conservation and sustainable development. Various absorption methods have emerged; the majority of them still suffer from defects including low removal efficiency, a complicated preparation process, and high cost. Herein, we present a highly porous and mechanical resilient bacterial cellulose (BC) carbon aerogel directly from BC hydrogel via facile directional freeze-drying and high-temperature carbonization. The resultant BC carbon aerogel showed excellent mechanical compressibility (maximal height compression ∼99.5%) and elastic recovery due to the porous structure. Taking advantages of the high thermal stability and superhydrophobicity, the BC carbon aerogel was directly used as a versatile adsorbent for oil/water separation. The result demonstrated that the BC carbon aerogel showed super oil/water separation selectivity with the oil absorption capacity as high as 132-274 g g

Background Ideal bowel cleansing regimens should be both effective and well tolerated. The European Society of Gastrointestinal Endoscopy recommends 4L Polyethylene Glycol (PEG) as the standard regimen for the bowel preparation (BP). This large volume of PEG ensures a better-quality bowel cleansing but might be poorly tolerated amongst the Chinese population given their different characteristics. The current study compared the 3L and 4L PEG with regard to their effectiveness, tolerability, and safety amongst Chinese patients to identify the better suitable bowel cleansing method for this population. Methods This study employed a prospective, observer-blinded, randomized and controlled design in a high-volume endoscopic center. Consecutive patients undergoing colonoscopy were randomly assigned (1:1) to the 3L-PEG or 4L-PEG group. The quality of bowel cleansing, procedure time, adenoma detection rate (ADR), patient tolerance, and adverse events were compared. Results A total of 330 patients were included in the study. The quality of the bowel cleansing (Boston Bowel Preparation Scale) for both the whole intestine and each segment showing no significant differences between the groups. No significant differences were present with regard to the procedure time or ADR. The incidences of adverse events such as nausea (P = 0.001) and bloating (P

Nanopapers derived from nanofibrillated cellulose (NFC) are urgently required as attractive substrates for thermal management applications of electronic devices because of their lightweight, easy cutting, cost efficiency, and sustainability. In this paper, we provided a facile fabrication strategy to construct hybrid nanopapers composed of dialdehyde nanofibrillated cellulose (DANFC) and silver nanoparticles (AgNPs), which exhibited a favorable thermal conductivity property. AgNPs were in situ proceeded on the surface of DANFC by the silver mirror reaction inspired by the aldehyde groups. Owing to the intermolecular hydrogen bonds inside the hybrid nanopapers, the DANFC enables the uniform dispersion of AgNPs as well as promotes the formation of the hierarchical structure. It was found that the AgNPs-coated DANFC (DANFC/Ag) hybrid nanopapers could easily form an effective thermally conductive pathway for phonon transfer. As a result, the thermal conductivity (TC) of the obtained DANFC/Ag hybrid nanopapers containing only 1.9 vol % of Ag was 5.35 times higher than that of the pure NFC nanopapers along with a significantly TC enhancement per vol % Ag of 230.0%, which was supposed to benefit from the continuous heat transfer pathway constructed by the connection of AgNPs decorated on the cellulose nanofibers. The DANFC/Ag hybrid nanopapers possess potential applications as thermal management materials in the next-generation portable electronic devices.

The cellulose microfibril-precipitated calcium carbonate (CMF–PCC) composite filler has been studied in improving the printing and optical properties of ordinary paper. However, the effect of CMF–PCC composite filler on the properties of Xuan paper, especially the ink diffusion properties, has rarely been investigated. In this study, the CMF–PCC composite filler was prepared by double-exchange reaction. The effects of CMF–PCC composite filler on the physical properties and ink diffusion properties of Xuan paper were detailedly studied. The results showed that the PCC particles in the CMF–PCC composite filler were rhombohedral calcite, with a uniform particle size and high adhesion rate, under the optimum reaction conditions. The Xuan paper filled with the CMF–PCC composite filler had higher tensile strengths and opacity than the conventional PCC or GCC loading. Notably, the CMF–PCC composite filler can effectively improve and regulate the Chinese ink diffusion properties of Xuan paper.

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.

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*

Purpose: Somatic inactivating mutations in ARID1A, a component of the SWI/SNF chromatin remodeling complex, are detected in various types of human malignancies. Loss of ARID1A compromises DNA damage repair. The induced DNA damage burden may increase reliance on PARP-dependent DNA repair of cancer cells to maintain genome integrity and render susceptibility to PARP inhibitor therapy. Experimental Design: Isogenic ARID1A−/− and wild-type cell lines were used for assessing DNA damage response, DNA compactness, and profiling global serine/threonine phosphoproteomic in vivo. A panel of inhibitors targeting DNA repair pathways was screened for a synergistic antitumor effect with irradiation in ARID1A−/− tumors. Results: ARID1A-deficient endometrial cells exhibit sustained levels in DNA damage response, a result further supported by in vivo phosphoproteomic analysis. Our results show that ARID1A is essential for establishing an open chromatin state upon DNA damage, a process required for recruitment of 53BP1 and RIF1, key mediators of non-homologous end-joining (NHEJ) machinery, to DNA lesions. The inability of ARID1A−/− cells to mount NHEJ repair results in a partial cytotoxic response to radiation. Small-molecule compound screens revealed that PARP inhibitors act synergistically with radiation to potentiate cytotoxicity in ARID1A−/− cells. Combination treatment with low-dose radiation and olaparib greatly improved antitumor efficacy, resulting in long-term remission in mice bearing ARID1A-deficient tumors. Conclusions: ARID1A-deficient cells acquire high sensitivity to PARP inhibition after exposure to exogenously induced DNA breaks such as ionizing radiation. Our findings suggest a novel biologically informed strategy for treating ARID1A-deficient malignancies.

We used cellulose and a nonclassical mineralization process to fabricate a bioinspired nanohybrid material that exhibited structural features and properties similar to those of human hard tissues. We made a hydrogel with highly compacted and aligned cellulose nanofibers. We thoroughly mineralized the cellulose hydrogel with hydroxyapatite nanocrystals, using poly(acrylic acid) as a soluble template for precursor minerals, which infiltrated the nanocompartments of the aligned cellulose nanofiber network. The ultrastructure and mechanical properties of the mineralized gels were strikingly similar to those of bone and dentin, which supports further use of cellulose-based fibrillary materials as affordable, biocompatible scaffolds for repair and regeneration of hard tissues. The versatility of the bioinspired mineralization processes used here can broaden the applications of these cellulosic nanohybrids.

A new Pb(II) complex, [Pb(8-OQ)(4-NB)], where 8-OQ = 8-hydroxyquinolinate, 4-NB = 4-nitrobenzoate, has been synthesized and characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. The single crystal X-ray analysis reveals that the complex possesses a tetranuclear Pb4O4 cubane structure. The Pb(II) atom is coordinated by three triply bridging phenolic hydroxyl O atoms of 8-OQ ligands, then the tetranuclear Pb system is formed resulting in a tetrahedral cage. The interaction of complex with HS-DNA in Tris buffer was studied by UV−vis absorption spectrum and fluorescence ethidium bromide displacement experiment with an intrinsic binding constant of 1.52×104 M-1 and a linear Stern–Volmer quenching constant of 6.77×103 M-1. Anticancer activity against MCF-7, HepG-2 and A549 cell lines of complex was also determined by the MTT-based assay. The results showed the complex can inhibit proliferation of these three kinds of tumor cells and is less cytotoxic than cisplatin.

Bacterial cellulose is an attractive material due to its outstanding biocompatibility, nanometer size and high purity, but the difficulty of dispersing has restricted its wide applications. In this study, chitosan was grafted onto bacterial cellulose by Schiff base reaction, and then obtained the nano-sized fibrils by ultrasonic dispersion process. Different concentrations of NaIO4 with various time and temperature were applied, and the maximum grafting amount of chitosan was 12.38%. The obtained products were characterized by FTIR, XRD, SEM and TEM. From the dispersibility and stability behavior research, the suspension containing chitosan was more uniform and showed better acid and temperature stability. It can also be observed in SEM and TEM images that the bacterial cellulose were dispersed into single ones and the diameter of the isolated fibril was 30–80 nm.

Poor adhesion to resin and low axial compressive strength are two prominent problems for application of aramid in fiber-reinforced composites. Simultaneously enhancing interfacial shear strength (IFSS) and compressive strength is still challenging. Herein, 4-(bromomethyl) benzoic acid (BBA) was utilized as external cross-linker to modify (Poly-p-phenylene-benzimidazole terephthalamide) (PBIA) fibers through post-swelling process. It was confirmed that bromomethyl groups of BBA could react with benzimidazole units of PBIA upon 80 °C and carboxyl of BBA could form cross-linking upon 300 °C by decarboxylation coupling reaction. Therefore, both surface grafting and bulk cross-linking can be obtained simultaneously by controlling temperature during modification process. After modification, IFSS and compressive strength of PBIA fibers are enhanced by nearly 27% and 100% respectively while maintaining excellent mechanical properties. Therefore, the method is nearly non-destructive and effective to simultaneously improve IFSS and compressive strength of PBIA fibers.

The poor atomic oxygen (AO) resistant property of polyimide (PI) film is the bottom problem for its application in aerospace. Coating SiO2 layer on PI is expected to solve this problem efficiently ...

The permeability modeling of self-healing due to calcium carbonate precipitation in cement-based materials with mineral additives was studied in this work. The parameters of calcium carbonate precipitation during self-healing were simulated. A permeability modeling of self-healing, combined with numerical simulation of calcium carbonate formation, was proposed based on the modified Poiseuille flow model. Moreover, the percentage of calcium carbonate in healing products was measured by TG-DTA. The simulated results show that self-healing can be dramatically promoted with the increase of pH and Ca2+ concentration. The calculated result of permeability is consistent with that measured for cracks appearing in middle or later stages of self-healing, it indicates that this model can be used to predict the self-healing rate to some extent. In addition, TG-DTA results show that the percentage of calcium carbonate in healing products is higher for mortar with only chemical expansion additives or cracks appearing in the later stage, which can more accurately predict the self-healing rate for the model.

Herein, we explore a new carbon source for preparation of carbon quantum dots (CQDs) with controllable composition using a porous organic polymer (POP) derived porous carbon via a nitric acid oxidation method. The POP used for the preparation of CQDs was synthesized by mechanochemical Friedel–Crafts alkylation under solvent free conditions. Using the as-prepared CQDs, we develop a simple and effective electrochemiluminescence (ECL) detection method for dopamine (DA) using a CQD/chitosan–graphene composite modified glassy carbon electrode (GCE). Both the electrochemical and ECL behaviors were studied in detail with ammonium persulfate as a coreactant. The complementary structure and synergistic function of the composite give the ECL sensor special properties. Apart from the high stability, it also presents good repeatability and high sensitivity to DA with a wide linear range from 0.06 to 1.6 μM. And a satisfactory detection limit of 0.028 μM (S/N = 3) was achieved for the prepared sensor. Furthermore, the ECL also shows high selectivity toward DA with an excellent interference resistance ability at a high concentration ratio of 100 (Cinterference : CDA = 100). In addition, the ECL sensor was successfully applied for effective detection and quantitative analysis of the actual dopamine in human body fluids for disease diagnosis and pathological studies.

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%).

A novel pretreatment method named nitrogen-assisted headspace solid-phase extraction (NA/HS-SPE) was developed for the analysis of volatile organic pollutants in water, sediment, honey, and juice. The target compounds including trichloroethylene, tetrachloroethylene, 1,2-dichlorobenzene and 1,2,3,5-tetrachlorobenzene were measured via gas chromatography with an electron capture detector. Factors affecting the extraction efficiency such as the adsorbent, elution solvent, purge gas type, gas flow rate, salinity, pH, temperature and purge time were optimized using ultrapure water via a single factor optimization method. Under optimum conditions, the recoveries were 90.76–100.22%. The limits of detection (LODs) and limits of quantitation (LOQs) were 0.002–0.0371 μg L−1 and 0.008–0.122 μg L−1, respectively. The method can be used to analyze pollutants in rainwater, river water, underground water, sediment, honey, and juice. Recovery tests using real samples at three concentrations showed that the recoveries ranged from 71.29% to 116.06% with relative standard deviations (RSDs) ranging from 0.9% to 15.3%. In addition, the method remained satisfactory when the SPE cartridges were used three times. The NA/HS-SPE method can be easily carried out in the laboratory with no matrix interferences.

Recycled paper and some hardwood paper often display poorer mechanical properties, which hinder its practical applications and need to be addressed. In this work, cellulose nanofibrils (CNFs) obtained by a combined process of enzymatic hydrolysis and grinding (EG-CNFs), grinding and microfluidization (GH-CNFs) or TEMPO-mediated oxidation and grinding (TE-CNFs) were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Moreover, CNFs were made into films on which some characterizations including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and UV–Vis transmittance spectroscopy were implemented. Results showed that CNF fibrillation was promoted as times of passes increased in microfluidization, and CNFs pretreated by enzyme possessed shorter length. Crystallinity of CNFs was related to CNF manufacturing methods, while CNF films’ transparency was correlated to CNF diameter distributions. Moreover, CNFs were applied with different dosages on recycled and hardwood paper. Lengths of CNFs, strength of CNF network, and pulp properties were critical factors affecting the mechanical strength of CNFs-enhanced paper. GH-CNFs showed better strengthened effect on tensile strength of paper than TE-CNFs and EG-CNFs. The best overall improvement was achieved at GH-CNF10 dosage of 5.0 wt% on hardwood paper. The increment of tensile index, burst index, and folding endurance were 108.32%, 104.65%, and 600%, respectively. This work aims to find out the relationship between production methods and morphologies of CNFs and how the morphological characteristics of CNFs affecting the mechanical performance of paper when they are added as strength additives.

This work aimed to study the stabilization mechanism induced by different morphologies of cellulosic fiber in O/W emulsion. Three types of cellulosic fibers were named squashed cellulose, incompletely nanofibrillated cellulose, and completely nanofibrillated cellulose, respectively. Squashed cellulose acted as barriers between the droplets to stabilize emulsion via depletion flocculation, whereas incompletely nanofibrillated and completely nanofibrillated cellulose formed covering layer via interfacial adsorption and connected adjacent droplets to create the droplet-fiber network structure via bridging flocculation. Differently, completely nanofibrillated cellulose formed the denser covering layer leading to a more stability of droplet. Importantly, it had the higher capacity of bridging flocculation, which can tightly connect the adjacent droplets to form a stronger droplet-fiber 3D network structure. Consequently, in rheological analysis including creep compliance, and dynamic modulus, the corresponding emulsions showed excellent anti-deformation ability and dynamic stability. This study provides practical guidance on the productions of foodstuff and cosmetic.

Iron selenide (FeSe) is an iron-based superconductor which shows unique properties, including strongly anisotropic superconducting gap, paramagnetism in undoped compound and extremely small Fermi pocket size. In this work, we demonstrate that the sizes of electron and hole pockets in FeSe monolayer become much smaller than those in bulk. The Fermi energy is in the order of a few meV and can be fine-tuned by the thickness of graphene layers underneath. Despite the low carrier density, the FeSe monolayers grown on trilayer or multi-layer graphene are superconducting. The superconducting gap size is sensitive to the Fermi energy of the hole band. Remarkably, the FeSe monolayer provides the opportunity to study the physics in the crossover regime where the Fermi energy and superconducting gap are comparable to each other.

In current study, CNFs produced by different mechanical methods, were used to improve the mechanical properties of recycled paper. The result showed the morphology of CNFs had great impact on reinforced effect and the length of fibrils determined their contribution in recycled paper strength. For different CNFs with similar diameter, the higher aspect ratio resulted in better reinforced effect. The CNFs produced by microfluidic homogenization and suitable PFI milling conditions (RM-CNF1) got best reinforced effect which improved tensile index and burst index by 35.5 % and 49.4 % at 5.0 wt% addition, respectively, due to their high aspect ratio. Although the CNFs produced by ball milling and ultrasonication (BU-CNF2) still had many bundles that were not fibrillated completely, their reinforced effect just below RM-CNF1 due to their special morphology and high retention rate. This work aims to study the influence of CNFs on recycled fibers reinforcement.

The development of biopolymer films is crucial for the replacement of conventional plastics. Tremendous effort is made to improve their performances by introducing biopolymers through the film manufacturing process. Herein, a sandwich-architectured film was proposed to efficiently improve the adhesion between the PS and PLA layers by using octenyl succinic anhydride-modified pea starch (OMPS) layer as the interlayer, leading to a highly mechanically enhanced interpenetrating network. Accordingly, the properties of the films were enhanced due to the synergism effect of sandwich architecture. In particular, the WVP value of the sandwich-architectured films (0.25 ∼ 0.89×10-10g·m-1·s-1·Pa-1) decreased more than 7-fold compared with the OMPS20 film, and the OP value of the sandwich-architectured films (0.256 ∼ 1.229×10-12cm3·m·m-2·s-1·Pa-1) decreased more than 10-fold in comparison to the PLA film. Benefitting from the characteristics investigated above, the films exhibited a favorable effect on strawberry storage. Overall, the fabricated eco-friendly sandwich-architectured films have shown great potential for biodegradable packaging applications.

An intermolecular hydroalkylative dearomatization of naphthalenes with commercially available α-amino acids is achieved via visible-light photoredox catalysis. With an organic photocatalyst, a series of multi-substituted 1,2-dihydronaphthalenes are obtained in good-to-excellent yields. Intriguingly, by tuning the substituents at the C2 position of naphthalenes, formal dearomative [3+2] cycloadditions occur exclusively via a hydroalkylative dearomatization-cyclization sequence. This overall redox-neutral method features mild reaction conditions, good tolerance of functionalities, and operational simplicity. Diverse downstream elaborations of the products are demonstrated. Preliminary mechanistic studies suggest the involvement of a radical-radical coupling pathway.

BACKGROUND Rhubarb and astragalus capsule (RAC) has been used in the clinical treatment of chronic kidney disease for decades. However, the mechanism of RAC has not been fully elucidated. This study aimed to investigate the protective effect and mechanisms of RAC on unilateral ureteral obstruction (UUO)-induced renal interstitial fibrosis. MATERIAL AND METHODS The main components of RAC are detected by high-performance liquid phase (HPLC). A rat model of UUO was established, and a subset of rats underwent treatment with RAC. Renal function and renal pathology were examined at 14 days and 21 days after the UUO operation. Renal cell apoptosis was detected by TUNEL staining. The levels of Bcl-2 and Bax in the kidney were examined by western blotting, and the levels of collagen I, alpha-SMA, transforming growth factor (TGF)-s1, and p38 MAPK in the kidneys were detected by immunohistochemistry. RESULTS High-performance liquid phase chromatography showed that RAC contained 1.12 mg/g aloe-emodin, 2.25 mg/g rhein, 1.75 mg/g emodin, and 4.50 mg/g chrysophanol. Administration of RAC significantly decreased the levels of urinary N-acetyl-s-D-glucosaminidase (NAG), serum blood urea nitrogen (BUN), and creatinine (Scr) and also reduced renal tissue damages and interstitial fibrosis induced by UUO in rats. Moreover, the increased levels of collagen I, alpha-SMA, TGF-s1, p38 MAPK, and the Bax/Bcl-2 ratio, as well as cell apoptosis in the kidney, were induced by UUO, and were all found deceased by RAC treatment. CONCLUSIONS RAC can improve the renal interstitial fibrosis induced by UUO, and the mechanism may be related to inhibition of renal tubular cell apoptosis via TGF-s1/p38 MAPK pathway.

Objective This study aimed to investigate the effect of high fluoride on runt-related transcription factor 2 (Runx2) expression and to explore the possible relationship among Runx2, forkhead box o1 (Foxo1) and kallikrein 4 (KLK4) in high fluoride-treated ameloblasts. Design Ameloblast-like cells (LS8 cells) were exposed to various concentrations of sodium fluoride (NaF) for up to 48 h. Runx2 expression was downregulated by gene silencing, and Foxo1 expression was up- and downregulated by gene overexpression and silencing, respectively. The mRNA and protein levels of Runx2, Foxo1, KLK4 and matrix metalloproteinase 20 (MMP20) were detected by qRT-PCR and western blotting. Results Runx2 expression was decreased in a dose- and time-dependent manner in NaF-treated LS8 cells. The knockdown of Runx2 markedly decreased KLK4 expression in LS8 cells under NaF conditions. However, the variation trend of MMP20 was unclear. In addition, forced Foxo1 expression led to significant upregulation of Runx2 in LS8 cells under NaF conditions. In contrast, the knockdown of Foxo1 markedly decreased the Runx2 protein levels under NaF conditions. Moreover, Foxo1 downregulation markedly decreased runx2 mRNA levels, and this inhibition in LS8 cells was intensified when combined with NaF treatment. Conclusion The results indicated that NaF reduces Runx2 expression in LS8 cells and that decreased Foxo1/Runx2 expression induced by high fluoride is a cause of low KLK4 expression.

Surface modification of aramid fiber to improve its interfacial adhesion with epoxy resin is always a meaningful topic. Herein, a layer of coordination polymer (CP) was introduced on aramid fiber surface via chemical grafting, and the thickness of CP layer could be controlled by reaction time. The experimental results showed that CP layer with a thickness of 40 nm to 60 nm is optimal for fiber’s interfacial properties. Also, it is found that this CP layer could be degraded by HCl, making the fiber recyclable in fiber/resin composite with typical fabrication techniques.

As one of the most important high-performance fibers, the facing challenges of poly(p-phenylene terephthalamide) fibers are the poor compressive properties and weak adhesion with resins. Here we fabricated a novel high performance aramid fiber containing benzimidazole moieties and chloride substitutions. The results of Fourier transform infrared spectra indicate the presence of benzimidazole moiety strengthens hydrogen bonds. The results of insolubilization in H2SO4 and electron paramagnetic resonance spectra of the captured radical intermediate indicate chemical crosslinking reaction occurs during heat treatment, and the degree of crosslinking shows an increasing trend with increasing chloride substitutions. The aggregation structure of aramid fibers obtained is studied in detail. The fibers show excellent tensile strength (2.58–3.42 GPa) and initial modulus (88.4–112.0 GPa). What is more, the values of compressive strength of those aramid are highly improved owing to the reinforcement of cohesive strength resulting from crosslinking and strong hydrogen bonding interactions. The highest compressive strength is 51.5% higher than that of poly(p-phenylene terephthalamide) fibers. Interestingly, interfacial shear strength of those aramid fibers is also improved compared to poly(p-phenylene terephthalamide) fibers. Keywords: Aramid fibers, Chemical crosslinking, Hydrogen bond, Compressive properties

Hierarchical-structured electrodes having merits of superior cycling stability and high rate performance are highly desired for next-generation energy storage. For the first time, we reported a compressible and hierarchical porous carbon nanofiber foam (CNFF) derived from a sustainable and abundant biomaterial resource, bacterial cellulose, for boosting the electrochemical performance of potassium-ion batteries. The CNFF free-standing electrode with a hierarchical porous three-dimensional structure demonstrated excellent rate performance and outstanding cyclic stability in the extended cycling test. Specifically, in the long-term cycling-stability test, the CNFF electrode maintained a stable capacity of 158 mA h g–1 after 2000 cycles at a high current density of 1000 mA g–1, which has an average capacity decay of 0.006% per cycle. After that, the CNFF electrode maintained a capacity of 141 mA h g–1 at a current density of 2000 mA g–1 for another 1500 cycles, and a capacity of 122 mA h g–1 at a current den...

The selective fluorination of aramid fiber surface was reported by Fe3+ coordination on the benzimidazole unit. After the coordination, both of the two parts in benzimidazole unit, benzene ring and imidazole ring, take priority in the reaction with the fluorine gas, while the reaction with the amide bond is restrained. In this way, selective fluorination on benzimidazole unit is achieved, with the surface polarity increasing and chain scission behavior suppressed simultaneously. What’s more, the increased surface polarity enables the improvement of the interfacial shear strength by 24%, compared with that in a traditional fluorination way. In all, the study offers an easy and effective strategy for the regulation and controlling of direct fluorination reaction, and it provides a guideline for further adjustment of the reaction mechanism to meet the requirement in other applications.

Green electronics on biodegradable substrates from natural sources have gained broad interest because of the advantages of being biodegradable, recyclable, sustainable, and cost-efficient. This study presents a low-cost, yet simple extraction and purification method that explores aqueous extraction and precipitation with ethanol for the synthesis of galactomannan films. In salient contrast to the other materials of natural origin, the process to obtain galactomannan films is energy efficient and environmentally friendly. As an alternative biodegradable material, galactomannan has direct relevance to the recent emerging biodegradable or transient electronics. The galactomannan substrate with temperature sensors and electrodes fabricated from zinc, a biodegradable material noted for its essential biological function, demonstrates a high-precision measurement of temperature and high-fidelity monitoring of electrophysiological signals (electromyogram or electrocardiogram). The resulting disposable sensors disappear without a trace in water and produce environmentally benign end products that could even be used for alkaline soil amendments. The set of materials explored in this study is also stable in organic solutions, enabling solvent-based fabrication that may be combined with recent advances in additive manufacturing techniques for a novel manufacturing method.

Antibiotic contamination in agricultural lands through manure application causes changes in soil enzyme activity and the abundance of microbes, which may affect the fate of agrochemicals. A clear understanding of antibiotic-pesticide interactions is very limited. The objective of this study was to investigate the effect of oxytetracycline (OTC) on the persistence of triazine and chloroacetanilide herbicides in soil under a combined application scenario. Soil enzyme activity and the abundance of soil microbes disturbed by OTC were measured. The results showed that OTC inhibited the dissipation of the herbicides and the effect depended on OTC concentration. For example, the half-lives of acetochlor increased from 6.9 days to 21.6 days with the presence of OTC at 50 mg/kg. It was also found the dissipation of the herbicides would still be affected after a month of OTC exposure at high concentration. Co-application also decreased activity of soil urease, dehydrogenase and catalase during earlier incubation periods, then recovered gradually. Furthermore, OTC reduced the abundance of fungi and bacteria, which might relate to inhibition of herbicide dissipation. Co-application of antibiotics and herbicides resulted in greater herbicide persistence, possibly increasing risk of environmental contamination.

The oxidation residue coming from the process of production of PTA is an important secondary resources. PTA residue was used as raw material, and the battery grade cobalt carbonate was made after r...

The presence of organochlorine pesticides (OCPs) in dairy products can lead to human exposure. This study investigated the behavior of OCP residues in milk during yogurt and cheese production. Gas chromatography with electron-capture detection (GC-ECD) was used to detect α-hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), γ-HCH, g-chlordane, and α-chlordane in fresh milk, yogurt, and cheese. The results showed that fermentation reduced the residual concentration of OCPs in yogurt, with processing factors (PFs) ranging from 0.42 to 0.64. The reductions in residue levels during fermentation were due to the activity of the starter. The cheese making process increased the residual concentration of OCPs in cheese compared to raw milk, with PFs ranging from 2.37 to 4.93. Additionally, milk, yogurt, and cheese samples were purchased from local markets and OCP levels were analyzed. The target OCPs ranged from ND to 16.50 μg/kg in these samples.

Here is reported the novel determination of hydrogen peroxide by electrochemiluminescence using a chitosan–graphene composite film doped cadmium-tellurium quantum dot modified glassy carbon electrode. The cadmium-tellurium quantum dots were studied by absorption and fluorescence spectroscopy. Scanning electron microscopy and electrochemical impedance spectroscopy were used to characterize the structure morphology of the composite matrix. The electrochemiluminescence emission was linear with the concentration of hydrogen peroxide in the range of 3.5 × 10−7 to 1.1 × 10−5 M with a determination limit of 2.1 × 10−7 M. Furthermore, the modified electrode showed excellent reproducibility and stability.

In this study, the eco-friendly heteropoly acids-phosphotungstic acid (PTA) was chosen as a catalyst to assist neutral deep eutectic solvents (DESs) for deconstructing corn straw. The reactions were performed with a shorter time at 110–150 °C than other DES system. The results revealed that most of the lignin (86.1 %) and hemicellulose (89.7 %) were removed while cellulose was obtained in high yields (88.9–94.3 %). Benefiting from the removal of hemicellulose and lignin, the enzymatic digestibility of pretreated materials was noticeably boosted to 94.4 %, which was 5.3-fold higher than the untreated corn straw. Meanwhile, the regenerated lignin nanoparticle was acquired with a relatively high purity (more than 85 wt%), low and homogeneous molecular weight (5669−2437 g/mol). Furthermore, the PTA/DES demonstrated excellent cycle performance. Overall, technically feasible PTA catalyzed DES pretreatment presented in-depth analysis for effective deconstruction of corn straw recalcitrance for crops valorization in the future.

Ethnopharmacological relevance Rheum palmatum L; Astragalus membranaceus (Fisch.), is referred to as ‘Dahuang, Huangqi’ in China. As an important medicinal plant, the rhizome of rhubarb and astragalus is traditionally used in the treatment of kidney diseases associated with renal failure, inflammation and tumors. Aim of the study: This study aimed to investigate the effect of a drug-containing serum of rhubarb-astragalus capsules (composed of rhubarb and astragalus) and to elucidate its mechanism in the epithelial-mesenchymal transformation of renal tubular epithelial cells. Materials and methods Epithelial-mesenchymal transformation (EMT) of HK-2 cells was induced by TGF-β1, and rhubarb-astragalus and losartan drug-containing serum from rats, as well as SB203580 (a specific inhibitor of p38 MAPK), were used. High-performance liquid chromatography analysis was performed to determine the main components of the drug-containing serum of rhubarb-astragalus from rats. Western blotting and immunofluorescence analysis were used to determine the levels of protein expression, and real-time quantitative PCR analysis was used to detect the levels of gene expression. Results The drug-containing serum of rhubarb-astragalus contained emodin (0.36 μg/ml) and danthraquinone (0.96 μg/ml). Rhubarb-astragalus significantly decreased the protein expression levels of α-SMA, FN, vimentin and N-cadherin in HK-2 cells that were increased by TGF-β1, while it significantly increased the E-cadherin protein expression level that was decreased by TGF-β1. Rhubarb-astragalus also significantly decreased the protein expression levels of TGF-β1 and p38 MAPK and the mRNA expression levels of α-SMA, vimentin, TGF-β1, p38 MAPK, Smad2 and Smad3 in HK-2 cells that were increased by TGF-β1. It is worth noting that SB203580 (a p38 MAPK inhibitor) had similar effects as rhubarb-astragalus in this study. Conclusion The drug-containing serum of rhubarb-astragalus can inhibit EMT in HK-2 cells by downregulating the TGF-β1/p38 MAPK/Smad2/3 pathway.

This study investigated the process intensification strategies for the pretreatment of Radiata Pine with the green deep eutectic solvent (DES) system composed of benzyltrimethylammonium chloride/formic acid (BTMAC/FA). The results showed that DES pretreatment drastically improved the delignification and hemicelluloses-removal capacity. The conducted process acceptably remained most of the cellulose in pretreated biomass (88.3%–91.8%). Benefiting from the overcoming of recalcitrance, the enzymatic digestibility of pretreated residues reached 92.4%. The efficient conversion was mainly ascribed to the lignin and hemicelluloses co-extraction. Meanwhile, the lignin yield and enzymatic saccharification was still largely maintained after five reuses. Further structural characteristics of lignin nanoparticles revealed that the lignin possessed high purity (95.19–97.51%), medium molecular weight (9600 to 6495 g/mol), and low polydispersity (ca 2.0), which was attributed to cleavage of ether bonds in lignin as well as linkages between lignin and hemicelluloses. Overall, this study illustrated that DES pretreatment was promising to achieve an efficient fractionation of woody biomass into fermentable glucose and high-quality lignin.

Bletilla striata polysaccharides (BSPs) are effective for anti-inflammatory, detumescence, and radicals scavenging, with important applications in the area of food chain, pharmacy science, and health care. In this study, we comprehensively studied the interplay between the polysaccharides' formation, physicochemical properties, rheological properties, and associated antioxidant activities of BSPs from different extraction methods. The crude polysaccharides obtained from Bletilla striata by using the hot water extraction (BSPs-H), alkali-assisted extraction (BSPs-A), boiling water extraction (BSPs-B), and ultrasonic-assisted extraction (BSPs-U) methods showed different molecular weights, monosaccharide compositions, glycosidic bond compositions, and zeta potentials, but with the same IR spectra characteristic and thermal stability. By the above-mentioned four kinds of extraction methods, the resultant BSPs exhibited various degrees of reticular and lamellar structure. All the BSPs solutions exhibited shear-thinning behavior with the increase of the shear rate. Among these BSPs, BSPs-A exhibited better DPPH and ABTS radical scavenging activities and reducing power, whereas BSPs-H showed better hydroxyl radical scavenging activities.