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This paper reports a graphene oxide (GO) confined strategy to synthesize reduced GO-coated lithium titanate (Li 4 Ti 5 O 12, LTO) microspheres using as-prepared TiO 2 microspheres and GO as raw materials. The obtained samples are characterized by X-ray diffraction, field emission scanning electron microscopy and spectrophotometer. Results show that the spherical LTO is formed with approximate 1 μm diameter after hydrothermal reactions, which is due to a confined effect of GO on the surface of TiO 2 spheres. Electrochemical tests reveal that the presence of rGO can increase the capacity and cycling stability of LTO anodes, especially at higher C rate. The 3 wt% rGO-coated LTO anodes present a higher reversible Li-ion storage with a specific discharge capacity of 131.6 mAh g −1 at 5 C and 97% retention even after 500 cycles, which are more excellent than those of pristine LTO. The GO-confined method is anticipated to synthesize other electrode materials with high electrochemical performances. [ABSTRACT FROM AUTHOR]

The silkworm forms cocoon to protect its pupa that survives for months inside the cocoon without being affected by various environmental stresses. To understand the possible mode of pupal survival within the cocoon encasement, we investigate the cause that protects the cocoon. During the end of the spinning process, we have isolated different bacterial species from the cocoon surface. These are identified using molecular techniques and checked for their abilities to form biofilm in vitro. The bacteria are able to form biofilm either individually or in consortia. Of which, Bacillus and Erwinia species are prominent biofilm formers. Interestingly, these bacteria have the ability to form biofilm on the cocoon mimetic surface of the silk protein Sericin Hope that contains only sericin. The origin and the behavior of the bacteria lead us to hypothesize the possible role of biofilm layer on the cocoon surface, which provides protection from adverse environmental conditions. [ABSTRACT FROM AUTHOR]

Different techniques are being developed for fabricating microcapsules; it is still a challenge to fabricate them in an efficient and environment-friendly process. Here, a one-step green route to synthesize silk protein sericin-based microcapsules without any assistance of organic solvents is reported. By carefully changing the concentration of calcium ions accompanied with stirring, the morphology of the microcapsules can easily be regulated to form either discoidal, biconcave, cocoon-like, or tubular structures. The chelation of Ca2+ and shearing force from agitation may induce the conformational transformation of sericin, which possibly results in the formation of microcapsules through the self-assembly of the protein subsequently. The as-prepared cocoon-like microcapsules exhibit pH-dependent stability. A potential application of microcapsules being fabricated from natural water-soluble silk protein sericin for controlled bioactive molecules loading and release system by a pH-triggered manner is quite feasible. [ABSTRACT FROM AUTHOR]

Abstract: This work presents a synthesis process and flocculation characteristics of an eco-friendly flocculant based on bamboo pulp cellulose (BPC) from Phyllostachys heterocycla. Ployacrylamide (PAM) was grafted onto the BPC by free-radical graft copolymerization in homogeneous aqueous solution. The optimal synthesis conditions of the bamboo pulp cellulose-graft-ployacrylamide flocculant (BPC-g-PAM) and its performance on wastewater treatments were investigated. A UV-based method was used to rapidly determine the degree of substitution (DS) of BPC. The results showed that, under the optimal synthesis conditions, the obtained BPC-g-PAM held a grafting ratio of 43.8% and DS of 1.31. Turbidity removal of the product reached 98.0% accompanying with the significant flocculation and sedimentation in target suspensions. The flocculation mechanism was explored by means of zeta potential method. For negatively charged contaminants, like kaolin clay particles, the BPC-g-PAM could remove the contaminants efficiently via bridging and charge neutralization in acidic or neutral environment. [Copyright &y& Elsevier]

• Crystallization rate of PEG/Cu composite was determined by heterogenous nucleation and diffusion of the PEG molecular chains. • Strong dependence of the PEG crystal growth in the PEG/Cu composite on the temperature was found. • Addition of Cu particles in PEG matrix supported more helical conformations of PEG molecular chains. Poly(ethylene glycol) (PEG) is used as phase change materials while the low thermal conductivity restricted the thermal storage efficiency. Incorporation of the metal particles (MPs) into PEG could enhance the thermal conductivity while the crystallization kinetic mechanism of the MP-filled PEG composites is altered. Flake MPs are characterized with layer structure and a large aspect ratio, while there are few research works related to the effect of flake MPs on the crystallization kinetic mechanism of flake MP-filled polymer composites. In this work, different micro flake copper (Cu) particles contents were introduced into the PEG matrix via the physical blending method. The Fourier transform infrared instrument (FT-IR) was used to characterize the chemical compatibility of the PEG/Cu composites. The differential scanning calorimetry (DSC) method was to characterize the crystalline kinetic mechanism of the micro flake Cu particle-filled polymer composites by using the isothermal model and non-isothermal model. It was found that the COC conformation of the confined PEG in the composites was altered, and more helical conformations were transferred from the zigzag conformations. The addition of the Cu particles in the PEG matrix enhanced the heterogeneous nucleation meantime hindered the diffusion of the PEG molecular chains. As a result, the crystallization rate of the PEG/Cu composites was optimized only when there was a middle Cu content in the PEG matrix (14.89 wt% in this work). Additionally, the PEG/Cu composites had 3D PEG crystal growth geometry in the isothermal crystallization process while the stronger dependence of the PEG crystal growth geometry on the temperature was found in the non-isothermal crystallization especially when the Cu amount was higher than 14.89 wt%. [ABSTRACT FROM AUTHOR]

Coating of PTFE on the fabrics is one facial method to obtain the hydrophobic/superhydrophobic property. However, the breathability of the PTFE-coated fabrics prepared by traditional methods (e.g., sputtering) is significantly affected. Electrospraying technology was able to create the pure PTFE coating layer on any substrates and the following sintering process is necessary to obtain the hydrophobic/superhydrophobic property. In this work, the PTFE-coated viscose fabrics were firstly prepared via electrospraying technology and then stabilized after 10 min sintering process with different temperatures ranging from 150 °C to 210 °C. The morphology, hydrophobicity, breathability, and water moisture transfer of the PTFE-coated viscose fabrics as well as the chemical compatibility between PTFE microparticles and viscose fabric were investigated. With increased sintering temperature, the PTFE coating layer on the viscose fabric became physically denser, which corresponded to the reduced breathability. Only when sintering temperature was equal to or higher than 190 °C, the stable hydrophobicity of PTFE-coated viscose fabric was found. When sintering temperature was increased from 190 °C to 210 °C, the contact angle hysteresis of the hydrophobic PTFE-coated viscose fabric decreased from 9.2° to 3.4° and the one-way water moisture transfer was enhanced. [Display omitted] • Critical sintering temperature to obtain hydrophobic PTFE-coated viscose fabric was found. • The R q value accounted for contact angle hysteresis of PTFE-coated viscose fabric. • Higher sintering temperature reduced crystallinity of PTFE coating layer. • Higher sintering temperature enhanced one-way water moisture transfer of hydrophobic PTFE-coated viscose fabric. • Higher sintering temperature reduced breathability of PTFE-coated viscose fabric. [ABSTRACT FROM AUTHOR]

[Display omitted] • Durable and restored fireproof cotton fabrics were prepared via a facile strategy. • Prominent fire resistance and durability to 50 LCs with LOI of 32.7% was achieved. • The reduction in washing durability can be recovered by feasible acetic acid soaking. • Improved fire resistance was due to graphitized carbon layers and C/N heterocycles. Novel, durably flame-retardant cotton fabrics with fascinatingly restorable fire resistance were prepared by simple grafting of phosphate and melamine, which contributed to a phosphorous-nitrogen (P/N) synergism. During the preparation process, phosphate was grafted with the hydroxyl groups of cellulose to form P-O-C bonds; subsequently, melamine reacted with the aldehyde groups of cellulose generated from phosphorylation to form P/N modified fabrics (P/N-Cotton). The P/N synergistic effect endowed cotton fabric with prominent fire resistance and durability. The Limit oxygen index (LOI) was as high as 51.1 ± 0.3% and was maintained at 32.7 ± 0.8% after 50 laundering cycles (LCs). The total heat release (THR) and peak values of heat release rate (pHRR) of P/N-Cotton were significantly reduced by 70.11% and 64.19%, respectively. Amazingly, the modified cotton fabrics exhibited restorable fire resistance once immersed into the acetic acid solution due to the ion exchange between Na+ from detergent and H+ from acetic acid. The LOI of P-Cotton and P/N-Cotton after 50 LCs can be restored to 32.4 ± 0.7% and 35.7 ± 0.7% from 20.8 ± 0.7% and 32.7 ± 0.8%, respectively. The analysis of gas-phase products and residual char demonstrated that the incorporation of phosphate and melamine facilitated cellulose fibers to convert to dense and stable graphitized carbon layers and carbon-nitrogen heterocycles, effectively protecting the fabric from decomposing to flammable gases. [ABSTRACT FROM AUTHOR]

[Display omitted] • L-cysteine is first introduced into cotton fabric facilely using its hydrochloride. • Two antimicrobics are efficiently loaded and their synergistic effects are studied. • The integration of TA can significantly improve antibacterial activity of Ag NPs. • The presence of Ag NPs evidently makes cytotoxicity of tannic acid negligible. In this paper, L-cysteine (Cys) is firstly bonded to the surface of cotton non-woven (CO) fabric as esterification. In this way, Ag+ and tannic acid (TA) are adsorbed onto the modified fabric via complexation and hydrogen bond interaction. After a sustainable one-step redox reaction, a Cys modified CO fabric decorated with Ag NPs and TA (CO-Cys-Ag-TA) is prepared. Because of the stabilizing effect of Cys and TA, the synthesized Ag NPs with a mean size of 88.9 nm are uniformly distributed on the modified fabric surface. Through the comparative test, it has been revealed that the antibacterial activity of Ag NPs is improved after loading TA, and the loading of Ag NPs significantly reduces the cytotoxicity of TA. In this context, the bacteriostatic reduction rate of CO-Cys-Ag-TA against S. aureus and E. coli is close to 100%, and its antibacterial activities are greater than 98.5% after 50 washing cycles. Meanwhile, its cell viability value reaches up to 88.0% with the presence of 0.1 mg/mL to 0.8 mg/mL CO-Cys-Ag-TA. [ABSTRACT FROM AUTHOR]

Abstract: We have demonstrated a facile approach for the fabrication of flexible and reliable sulfydryl functionalized PVA/PEI nanofibers with excellent water stability for the self-assembly of Au nanocrystals, such as Au nanoparticles (AuNPs), Au nanoflowers (AuNFs) and Au nanorods (AuNRs), used as the highly efficient surface-enhanced Raman scattering (SERS) substrates for the detection of rhodamine B (RhB). Various methods were employed to cross-link the PVA nanofibers with better morphology and porous structures after immersing in water for desired times. Various SERS-active Au nanocrystals, such as AuNPs, AuNFs, and AuNRs have been successfully synthesized. After the grafting of MPTES on the cross-linked PVA/PEI nanofibers, the Au nanocrystals can easily be self-assembled on the surfaces of the nanofibers because of the strong interactions of the Au–S chemical bondings. The Au nanocrystals self-assembled throughout the PVA/PEI nanofibers used as SERS substrates all exhibit enhanced SERS signals of RhB compared with their individual nanocrystals. It is mainly due to the close interparticle distance, mutual orientation and high density of “hot” spots, that can strongly affect the overall optical response and the SERS enhancement. By changing the amounts of the self-assembled AuNFs on the nanofibers, we can control the density of the “hot” spots. With the increased amounts of the AuNFs throughout the nanofibers, the SERS substrates show enhanced Raman signals of the RhB, indicating that the increased density of “hot” spots can directly lead to the SERS enhancement. The AuNFs/(PVA/PEI) SERS substrates show good sensitivity, reliability and low detection limit (10−9 M). The presented approach can be broadly applicable to the assembly of different types of plasmonic nanostructures and these novel materials with strong SERS enhancement can be applied in bioanalysis and biosensors. [Copyright &y& Elsevier]

Abstract: Deep infection of prosthesis is one of the most frequent complications after joint replacement. One of the most effective ways is to introduce directly some antibiotics in the local site of the surgery. In the present study, an antimicrobial composite has been fabricated using nano-hydroxyapatite particles as carriers for the antimicrobial drug of vancomycin hydrochloride (VAN) and the mixture of oxidation sodium alginate (OSA) and gelatin (GT) as a sticky matrix. Samples have been characterized using X-ray diffraction instrument (XRD), field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and Fourier transform infrared (FTIR) spectra, Brunauer–Emmett–Teller (BET) methods, the rotational rheometer and the texture analyzer. The release of VAN from nano-hydroxyapatite (nHAP) particles was detected by the ultraviolet–visible (UV–vis) spectrophotometer and then bactericidal property of the composite was evaluated using the Staphylococcus aureus (S. aureus) as a bacterial model. Experimental results showed that the composite possessed an adhesive property derived from the gel of OSA and GT, which implied that the composite could bond directly to the fracture surface of bones in surgery. Furthermore, VAN was loaded efficiently on the surface of nHAP particles and could be released slowly from these particles, which endowed the composite with an obvious and continuous antimicrobial performance. The sticky and antimicrobial composite may has a potential application in arthroplasty to overcome deep infection in a simple and direct manner. [Copyright &y& Elsevier]

Abstract: A novel, facile and green approach for the fabrication of H2O2, glutathione (GSH) and glucose detection biosensor using water-stable PVA and PVA/PEI nanofibers decorated with AgNPs by combining an in situ reduction approach and electrospinning technique has been demonstrated. Small, uniform and well-dispersed AgNPs embedded in the PVA nanofibers and immobilized on functionalized PVA/PEI nanofibers indicate the highly sensitive detection of H2O2 with a detection limit of 5μM and exhibit a fast response, broad linear range, low detection limit and excellent stability and reusability. [Copyright &y& Elsevier]

Abstract: The influence of soluble silk sericin (SS) protein on the formation of CaCO3 particles was investigated and the CaCO3 particles were then used as a template to synthesize the hydroxyapatite microspheres. The SS showed a strong preference to the mineralization of vaterite and the fine controls over the shape, size and uniformity of vaterite were carried out by the variation of pH value and reaction time in the presence of SS. Using the vaterites as a template, the homogeneous and monodispersed hydroxyapatite microspheres, copying faithfully the shape and size of original vaterites, were fabricated under the assistance of microwave irradiation. The research may provide a feasible method for the fabrication of hydroxyapatite-based biomaterials with controllable configuration. [Copyright &y& Elsevier]

Abstract: A facile and green approach has been demonstrated for the fabrication of highly uniform and monodisperse noble metal (Ag, Au, Pt) nanoparticles (NMNPs) in polyvinyl alcohol (PVA) nanofibers by combining an in situ reduction and electrospinning technique, which are used as efficient biosensor for the detection of H2O2. The small and stable NMNPs can be easily obtained in aqueous solution using EGCG as both reductant and stabilizer. Through electrospinning technique, uniform and smooth nanofibers can be obtained and the NMNPs with narrow size distributions are well dispersed in PVA nanofibers. The investigation indicates that the viscosity of the PVA solution play an important role in controlling the size of NMNPs. The fabricated AgNPs/PVA nanofibers functionalized electrodes exhibits remarkable increased electrochemical catalysis toward H2O2 and excellent stability and reusability. The biosensor allows the highly sensitive detection of H2O2 with a broad linear range span of the concentration of H2O2 from 10μM to 560μM. The rapid electrode response to the change of the H2O2 concentration is attributed to the fast diffusion of the H2O2 onto the surface of small AgNPs through the porous nanofibers structures. [Copyright &y& Elsevier]

[Display omitted] • Cellulose-based absorbents with the highest reported uranium uptake are achieved. • Homogeneous reactions are beneficial to grafting density and material utilization. • Excellent hydrophilicity contributes to rapid mass transfer and antifouling property. • The adsorbents could be filled into filtration columns for dynamic adsorption. • The adsorbents collect 50 mg uranium/g from simulated seawater in 24 d adsorption. Highly efficient extraction of uranium from seawater is regarded as an important guarantee for the promotion of nuclear electricity generation. Amidoxime based adsorbents are considered as the most promising materials for uranium recovery due to their high selectivity and binding capability to uranyl ions. Herein, natural celluloses with advantages of low cost, biodegradability, renewability were chosen as the raw materials. Moreover, amidoximated cellulose-based adsorbents are fabricated by two steps of homogeneous reactions including the Michael addition and amidoximation reaction. Compared with traditional surface grafting methods, both the grafting density of active adsorption sites and the utilization of raw materials could be greatly improved because of the lower steric hindrance as well as more exposed reactive sites during the homogeneous reactions. The adsorption capacity of our adsorbents can reach as high as 517.07 mg/g at pH = 7, one of the best cellulose-based adsorbents as far as we know. In addition, excellent hydrophilicity of the adsorbents, which is inherited from the natural cellulose, can endow them with enhanced mass transfer as well as resistance to marine pollutants. More importantly, the adsorption microspheres would be filled into filtration column for dynamic adsorption benefited from their aforementioned merits. The average adsorption capacity could maintain above 2.5 mg/g per day when the filtration column was exposed to simulated seawater for 24 days. All these characteristics make the amidoximated cellulose-based adsorbents potentially applicable to the uranium recovery from seawater. [ABSTRACT FROM AUTHOR]

• Sericin acts as a biosorbent to anchor iron ions (Fe3+) by coordination. • Fe 3 C is uniformly dispersed in sericin-derived carbon (SC) by in-situ synthesis. • The modification of Fe 3 C to SEI film is confirmed by ex-situ EIS analysis. • Fe 3 C/SC presents high reversible capacity, rate capability and stable cyclability. • The strategy can be used to design other carbon-based materials for energy storage. [Display omitted] Biomass-derived carbon is considered a promising alternative to commercial graphite anode because of its renewability and tunable physical/chemical properties. However, the specific capacity and rate capability of biochar anode materials must be further enhanced to satisfy the increasing energy demand. Here, we report a facile strategy to synthesize uniform Fe 3 C inserted sericin-derived porous carbon (Fe 3 C/SC) via coordination with Fe3+ ions to the carboxylate radicals of sericin protein. The obtained composite retains a hierarchical pore structure with an interconnected carbon scaffold. In particular, the embedded Fe 3 C nanoparticles (NPs) in the carbon matrix will serve as a catalyst for the modification of the solid electrolyte interphase (SEI) layer during the cycles, which effectively enhance reversible capacity. The resulting anode provides high reversible capacity (584.0 mAh g−1 at 0.1 A g−1 after 150 cycles), superior rate capability (259.0 mAh g−1 at 2 A g−1) and remarkable cycling stability under high current density (219.7 mAh g−1 retention at 2 A g−1 after 600 cycles). This composite is expected to be one of the most potential anode materials for lithium-ion batteries, owning to its cost-effective, facile synthesis and efficient performance with excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

The conventional skin sensor detection of human physiological signals can be an effective method for disease diagnosis and health monitoring, but the poor biocompatibility, low sensitivity and complex design largely limit their applications. Developing natural nanofiller-reinforced composites as strain biosensors is an appealing solution to reduce environmental impacts and overcome technical bottleneck. Herein, a versatile nature skin-inspired composite film as flexible strain biosensor was developed based on cellulose nanocrystals-polyaniline (CNC-PANI) composites by utilizing their percolated conductive network in polyvinyl alcohol (PVA) matrix. The composite electronic skin showed robust mechanical strength (50.62 MPa) and high sensitivity (Gauge Factor = 11.467) with easy water-induced self-healing abilities. Moreover, we investigated the functioning mechanism of percolated network and the sensory behavior determined by CNC nanocomposite alignment. The percolation threshold of CNC-polyaniline (PANI) was determined at 4.278% and 5% CNC-PANI composite film shows the best overall sensing property. It was also discovered that the sensitivity of this type of conductive-filler electronic skin can be divided into two separate regions at different strain range due to its percolated network. With films prepared by dry casting and dip coating, the alignment of CNC-PANI also contributes to this unique change in electrical property. Generally, our results demonstrated the mechanism and tunability of conductive nanofiller-based composite strain biosensors as a potential alternative to commercial synthetic sensors. • Conductive cellulose nanocrystals incorporated PVA composite strain biosensor were prepared. • The self-healed composite showed robust mechanical strength and excellent sensitivity. • Working mechanism of percolated network-based conductivity and sensitivity was reported. • Self-healing mechanism of PVA nanocomposite film was proposed. [ABSTRACT FROM AUTHOR]

Abstract: Cuprous oxide (Cu2O) nanocrystals have been successfully synthesized using copper acetate as precursors via a polyol process. The as-synthesized products were easily deposited on the surface of carbon nanofibres (CNFs) and then were characterized through XRD, FESEM, TEM and FTIR, etc. The photocatalytic performance of these composite films was evaluated using methyl orange as a model organic compound under visible light irradiation. Results showed that the shape of Cu2O nanparticles could be changed from irregular nanoparticle to cubic, flower-like particle assembled by Cu2O nanocubes with the change of the reaction conditions. All of these Cu2O/CNFs composite films showed the satisfied photocatalytic activity to methyl orange even after 3 cycles of degradation experiment due to the protectable function of carbon fibre films to the Cu2O nanocrystals. The Cu2O/CNFs composite films may offer a feasible method for the potential application of Cu2O nanocrystals in the treatment of organic contamination. [Copyright &y& Elsevier]

For preparation of an ideal wound dressing, a series of novel polyurethane-based asymmetric membranes with acetic starch and poly (ethylene glycol) as fillers were successfully fabricated by a combination of polymer-filler hybridization and immersion precipitation phase inversion. These resultant polyurethane-based asymmetric membranes consisted of an integral and dense skin layer supported by a porous sublayer as designed. The porosity and internal substructure of asymmetric membranes could be controlled by adjusting species and amount of fillers. The polyurethane-based asymmetric membranes showed promoted fluid absorption capability and controlled water vapor transmission, but could inhibit exogenous microorganisms invasion deriving from its dense skin layer. In vitro biodegradation assay indicated that the polyurethane/acetic starch composite membrane exhibited faster degradation behavior. These results indicated that the polyurethane-based asymmetric membranes prepared in this study has potential for application as an ideal wound dressing. [ABSTRACT FROM AUTHOR]

Abstract: The injectable chitosan/β-glycerophosphate (CS/GP) hydrogels were prepared with dexamethasone (Dex)/recombinant human bone morphogenetic protein (rhBMP-2) loaded hydroxyapatite nanoparticles (nHAP). The obtained samples were characterized by TEM, SEM, XRD and nitrogen adsorption tests, and the effect of Dex and rhBMP-2 on the mesenchymal stem cells (MSCs) was evaluated. The results showed that nHAP could be dispersed homogeneously in the matrix of injectable CS/GP hydrogels and the combination of Dex and rhBMP-2 could promote the proliferation and osteoblastic differentiation of MSCs, indicating that the prepared injectable CS/GP hydrogels with Dex and rhBMP-2 loaded nHAP have great potential in different orthopedic regenerative applications. [Copyright &y& Elsevier]

Abstract: In order to develop an eco-friendly superabsorbent composite, flax yarn waste (FYW) was used as raw material to synthesize a novel flax yarn waste-g-poly(acrylic acid-co-acrylamide) (FYW/PAA) superabsorbent composite. Acrylic acid (AA) and acrylamide (AM) were grafted onto the pretreated flax yarn waste (PFYW) by free-radical graft copolymerization in homogeneous aqueous solution. The properties and synthesis conditions of the FYW/PAA superabsorbent composite were investigated. As a result, the prepared FYW/PAA attained the best water absorbency of 875g/g in distilled water, 490g/g in rainwater and 90g/g in 0.9wt% NaCl solution. The urea loading percentage of FYW/PAA could be modulated by the concentration of urea. The release of urea from FYW/PAA in water showed a typical three-stages sustained release behavior. Meanwhile, a weight residue of 53.6wt% was attained after being buried in soil for 90d. [Copyright &y& Elsevier]

Abstract: A new, low-cost, and eco-friendly cellulose-based superabsorbent was successfully prepared from flax yarn waste. The method used was a free-radical graft copolymerization of AA and AM onto a cellulose backbone in a homogeneous aqueous solution. APS was used as the initiator in the presence of a crosslinker, MBA. The effects of various factors on water absorbency were discussed. The factors included reaction temperature, initiator amount, monomer amount, salt solution type, and solution pH. Under the optimized conditions, the water absorbencies of the obtained superabsorbent composite were 875g/g distilled water, 490g/g natural rainwater, and 90g/g 0.9wt% aqueous NaCl solution. The product also had excellent water retention and salt resistance properties. Fourier-transform infrared spectroscopy and scanning electron microscopy were employed to examine the structure of the prepared superabsorbent. [Copyright &y& Elsevier]

Porous calcium phosphate nanospheres were successfully fabricated by a simple sonochemical method, and used as a drug carrier of ibuprofen. Morphology, structure, ibuprofen storage capacity, and release rate of the calcium phosphate nanospheres were characterized using FE-SEM, TEM, Nitrogen adsorption, XRD, FTIR, and UV-vis adsorption spectroscopies. Results showed the obtained calcium phosphate nanospheres held a porous structure with an average diameter of 48.9 ± 17.42 nm. Moreover, the porous nanospheres possessed an adjustable load amount and release rate for ibuprofen by changing drug concentrations during the drug loading process. In addition, the effects of size and dispersancy of porous spheres on drug release rate were discussed, which was found that larger or agglomerate porous spheres could delay drug release process. This study indicated that porous calcium phosphate nanospheres were a perfect drug carrier for ibuprofen, which has potential application for the therapy of skeletal disease. [ABSTRACT FROM AUTHOR]

A novel silk fibroin spongy wound dressing (SFSD) incorporated with nano-Ag particles was prepared by coagulating with 1.25-5.0% (v/v) poly(ethylene glycol diglycidyl ether) (PGDE). The mechanical properties, moisture permeability and hygroscopicity of SFSD, and the nano-Ag release behavior from SFSD were evaluated. The results showed that the soft SFSD had satisfying tensile strength and flexibility, as well as excellent moisture permeability and absorption capability of wound exudates. The moisture permeability was 101 g/m2 per h and the water absorption capacity of SFSD was 595.2% and 251.9% of its own weight in dry and wet states, respectively. The nano-Ag in the SFSD was released continuously at a relatively stable rate in PBS resulting in a remarkable antibacterial property. A rabbit model was used to dynamically observe the healing process of full-thickness skin defects. Full-thickness wounds were created on the dorsal side of rabbits, which were covered with SFSD and porcine acellular dermal matrix (PADM) for comparison. The mean healing time of the wounds covered with SFSD was 17.7 ± 2.4 days, significantly shorter than that with PADM. The histological analysis showed that the epidermal cell layer formed with SFSD was very similar to normal skin, suggesting that SFSD may provide a good component for the development of new wound dressings. [ABSTRACT FROM AUTHOR]

Abstract: Hydroxyapatite-modified titanate nanowire scaffolds as alternative materials for tissue engineering have been developed via a titanate nanowire matrix assisted electrochemical deposition method. The macroporous titanate nanowire matrix on Ti metal was fabricated by a hydrothermal method, and then followed by an electrochemical synthesis of hydroxyapatite nanoparticles on titanate nanowire. The incorporation of titanate nanowire matrix with high oriented hydroxyapatite nanoparticles generates hierarchical scaffolds with highly osteogenic, structural integrity and excellent mechanical performance. As-prepared porous three dimensional interconnected hydroxyapatite-modified titanate nanowire scaffolds, mimicking the nature’s extracellular matrix, could provide a suitable microenvironment for tissue cell ingrowth and differentiation. The ceramic titanate nanowire core with HA nanoparticle sheath structure displays superhydrophilicity, which facilitates the cell attachment and proliferation, and induces the in vitro tissue-engineered bone. Human osteoblast-like MG63 cells were cultured on the hydroxyapatite-modified titanate nanowire scaffolds, and the results showed that the scaffolds highly promote the bioactivity, osteoconductivity and osteoblast differentiation. [Copyright &y& Elsevier]

Abstract: The paper reported a facile and green synthesis of silver nanoparticles by using hyaluronan (HA) as a reducing agent and soft template. The effect of reaction conditions on the Ag nanoparticle formation was investigated using UV–vis spectrophotometer, field-emission scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The application of Ag nanoparticles in surface enhanced Raman scattering (SERS) of HA was also evaluated. The results showed that the high pH value, temperature and molar ratio of HA to AgNO3 could accelerate the reduction rate of Ag+ and affect the Ag nanoparticle size. The Ag nanoplates could be fabricated with a low molar ratio of HA to AgNO3 by aging, which may be due to the selective adsorption and desorption of HA on the different crystallographic planes of Ag nanoparticles. The enhancement of Raman scattering effect was greatly dependent on the size and morphology of Ag nanoparticles. [Copyright &y& Elsevier]

Abstract: Plenty of techniques have been developed to modify the surface character of titanium (Ti) and its alloys in order to realize their biological bond to natural bone. In this work, a biomimetic process was employed to form a hydroxyapatite (HAp) coating on the alkali-heat treated Ti substrate in 1.5 times simulated body fluid (1.5×SBF) with the addition of a recombinant collagen-like protein. The coating was characterized using SEM-EDX, FESEM, and XRD. Results showed that the recombinant collagen-like protein could accelerate the preferential nucleation and directional growth along c axis of HAp on the pretreated Ti substrates. The investigation of in vitro cell cultivation showed that the existence of recombinant collagen-like protein in coating could improve the initial cell adhesion, proliferation and differentiation of MG-63 cells, which implied the materials possessed excellent biocompatibility and had a wide potential in biomedical application. [Copyright &y& Elsevier]

Abstract: In this work, the recombinant human bone morphogenetic protein 2 (rhBMP-2) gene was cloned from MG-63 cells by RT-PCR, and the protein was expressed in Escherichia coli expression system, purified by Ni–NTA column under denaturing conditions and refolded at 4°C by urea gradient dialysis. We found that the protein refolding yield was increased with the increase of pH value from pH 6.0 to pH 9.0. The yield was 42% and 96% at pH 7.4 and pH 9.0, respectively, while that at pH 6.0 was only 3.4%. The cell culture results showed that the rhBMP-2 refolded at pH 7.4 urea gradient dialysis had higher biological activity for MG-63 cell proliferation and differentiation than that refolded at pH 9.0 since pH 7.4 is closer to the conditions in vivo leading to the formation of dimers through the interchain disulfide bond. Moreover, the biological activity for MG-63 was promoted with the increase of rhBMP-2 concentration in the cell culture medium. This work may be important for the in vitro production and biomedical application of rhBMP-2 protein. [ABSTRACT FROM AUTHOR]

Abstract: Pectins were extracted from mulberry branch bark, a byproduct of the sericulture industry. A single-factor experiment was used to optimize the production conditions. Under optimal conditions, the galacturonic acid yields from bark with and without epidermis were 61.73±1.39% and 35.12±0.24%, respectively. The extracted pectins mainly consisted of galacturonic acid with a trace amount of neutral sugars, and the total galacturonic acid content in the pectins extracted from the bark without epidermis reached 85.46±2.76%. Pectins extracted from bark without epidermis had a higher degree of esterification (71.13±1.67%) than those extracted from bark with epidermis (24.27±2.89%). Pectin solution from bark without epidermis showed higher apparent viscosity, suggesting its higher gelation ability. Thus, the mulberry branch bark is a potential source of pectin with different degrees of esterification. [Copyright &y& Elsevier]

Abstract: A kind of cellulose whiskers were extracted from the branch-barks of mulberry (Morus alba L.) by an alkali treatment at 130°C and subsequently a sulfuric acid hydrolysis. AFM image showed that the diameter of obtained whiskers was ranged from 20 to 40nm. The chemical compositions analysis, FT-IR, XRD results indicated that the hemicellulose and lignin were removed extensively in the cellulose whiskers, with a crystallinity of 73.4%. The TGA curves implied a two-stage thermal decomposition behavior of cellulose whisker due to the introduction of sulfated groups into the crystals in the sulfuric acid hydrolysis process. The obtained whiskers may have the potential applications in the fields of composites as a reinforcing phase, as well as in pharmaceutical and optical industries as additives. [Copyright &y& Elsevier]

Abstract: Novel composite films of Bombyx mori silk fibroin (SF) and hydroxyapatite (HA) composite films, with glycerin as an additive, were fabricated by means of co-precipitation, where the theoretical HA content was varied from 2 (w/w)% to 31 (w/w)%. The structure and properties of the composite films were investigated by SEM, XRD, AFM, TGA and tensile testing. The results showed that the composite films were smooth and transparent with the uniform distribution of HA into the composites when the final HA content was lower than 21 (w/w)%. XRD and TGA data showed that the silk fibroin in the composites was predominantly in a β-sheet crystalline structure, which was induced not only by the addition of glycerin, also by the HA crystal growth during the composite fabrication, leading to the thermal stable composite films. On the other hand, the HA crystals had the anisotropic growth with high extent of lattice imperfection and the preferential orientation along c-axis, probably promoted by the silk fibroin. The mechanical testing results showed that both break strain and stress were declined with the increase of HA content in the composites, presumably due to the original brittleness of HA compound. [Copyright &y& Elsevier]

Abstract: Bombyx mori silk fibroin is of practical interest for its excellent intrinsic properties utilizable in the biotechnological and biomedical fields. Here, the silk fibroin films were pretreated with different methods and then used as the template for the hydroxyapatite (HA) crystal growth. To study the effect of silk films’ surface structure on the protein biomineralization, the films were immersed into 1.5 times simulated body fluid (1.5×SBF) to induce the HA deposition at 37°C. The results showed that an anisotropic growth of HA crystals was observed on the different films as judging from XRD, TEM and HRTEM data. This was thought that the positions and density of carboxyl groups, Cno groups on the surface of SF films may be different, which play the key effect on HA crystal growth. [Copyright &y& Elsevier]

Phase change fibers (PCFs) as a kind of composite material, the composition and spatial distribution of each phase have a great influence on its thermal and mechanical properties. In this article, PCFs with polyvinylpyrrolidone (PVP), polyvinyl butyral (PVB), and polyacrylonitrile (PAN) as sheath and 30% octadecane kerosene as core were prepared by coaxial electrospinning. It was found that octadecane had the highest supercooling degree when it was encapsulated in PVB. Thus, we used pure octadecane, 30% octadecane of isopropanol, chloroform, and kerosene solutions as core solutions, adjusted the fine structure of octadecane in PVB sheath, and four kinds of PCFs with different octadecane particle size and spacing were prepared. Successfully reduced the supercooling degree of octadecane. To compare the mechanical properties of the four fibers. It was found that the composite fiber obtained by using isopropanol as octadecane solvent had the most comprehensive mechanical performance. To find a universal method to control the distribution structure of phase change materials (PCMs) in fibers by coaxial electrospinning, we used PAN and PVDF as the sheath solution, pure octadecane, 30% octadecane in isopropanol, chloroform, petroleum ether, and kerosene solutions as a core solution to prepare the PCFs. Characterization results and analysis of the properties of solutions showed that only when the viscosity of the core and sheath solution was relatively low, it could obtain the bamboo-like structured fibers. And continuous core-sheath structured fibers could be obtained in two situations. First, the low viscosity of sheath solution and high viscosity of core solution; second, the high viscosity of sheath solution. [Display omitted] • Successfully prepared phase change fibers with different internal structures. • Optimize core distribution can suppress supercooling. • Optimize core distribution can improve mechanical properties. • Adjusting the solution viscosity can change the internal structure of the fiber. [ABSTRACT FROM AUTHOR]

Abstract: Porous 3D silk fibroin (SF) scaffolds were prepared directly from the SF solution with the addition of methanol and glutaraldehyde by a freeze-drying method. The scaffolds were then soaked in the simulated body fluid (SBF) for the deposition of hydroxyapatite (HA) crystals. The XRD and FTIR results showed that the SF were in β-sheet structure, resulting in the high thermal stability and mechanical properties of scaffolds. The XRD and AAS data revealed that the SF scaffolds could induce the continuous growth and enrichment of HA crystals onto the scaffolds with the extension of soaking time. The mechanical properties of scaffolds increased first with the HA-deposition within 3d of soaking, then it declined. During the full soaking period, no significant change was observed on the porosity and water-binding ability, which were kept at about 84% and 800%, respectively. The cell cultivation results showed that the scaffolds have the satisfied cell biocompatibility, which was promoted after the HA-deposition. This work suggests that the porous 3D SF scaffolds may be a potential candidate in the bone engineering. [Copyright &y& Elsevier]

The introduction of metal particles (MP) in the phase change materials (PCM) realizes the highly efficient thermal energy storage. However, a suitable carrier is necessary for PCM/MP composites for various applications. In this work, the polyethylene glycol (PEG) was used as PCM, five MPs including copper (Cu), aluminum (Al), silver (Ag), iron (Fe), and zinc (Zn) particles were used, and the viscose fabric was selected as a carrier for coating of PEG/MPs. The PEG was blended with different MPs with the same weight ratio of 72.3:23.7. Then, the PEG/MP-coated viscose fabric was prepared by applying PEG/MP composites on the viscose fabric with the same weight ratio of 90:10 and the PEG-coated viscose fabric (86.7:13.3) was set as reference. The phase transition of the prepared PEG/MP composites and the PEG/MP-coated viscose fabrics was investigated via the differential scanning calorimetry (DSC). The thermal behavior of the PEG/MP-coated viscose fabric was investigated via Alambeta device and the T-history method. The results revealed that the enthalpy of all the PEG/MP-coated viscose fabrics were larger than 100J/g. Besides, only the higher theoretical enthalpy of the PEG in the PEG/MP composites was found, and the MPs assisted in the higher crystallization of PEG. Results from the Alambeta device proved that the thermal conductivity was increased when MPs were introduced in the coated viscose fabric. T-history curves of all the PEG/MP-coated viscose fabric revealed that the heating constant of the phase transition stage mainly accounted for the quick heat transfer. • Metal particles (MPs) were considered as the good nuclei sites for the PEG nucleation while the viscose fiber did not. • Newton's cooling law was proposed to evaluate the T-history of PEG/MP-coated viscose fabric. • Higher efficient thermal energy storage relied on the improved heating constant of the phase transition stage. [ABSTRACT FROM AUTHOR]

Abstract: The Bombyx mori silk fibroin films (SFFs) were modified by a Cecropin B (CB) antimicrobial peptide, (NH2)-NGIVKAGPAIAVLGEAAL-CONH2, using the carbodiimide chemistry method. In order to avoid the dissolution of films during the modification procedure, the SFFs were first treated with 60% (v/v) ethanol aqueous solution, resulting a structural transition from unstable silk I to silk II. The investigation of modification conditions showed that the surface-modified SFFs had the satisfied antimicrobial activity and durability when they were activated by EDC·HCl/NHS solution followed by a treatment in CB peptide/PBS buffer (pH 6.5 or 8) solution at ambient temperature for 2h. Moreover, the surface-modified SFFs showed the smaller contact angle due to the hydrophilic antimicrobial peptides coupled on the film surface, which is essential for the cell adhesion and proliferation. AFM results indicated that the surface roughness of SFFs was considerably increased after the modification by the peptides. The elemental composition analysis results also suggested that the peptides were tightly coupled to the surface of SFFs. This approach may provide a new option to engineer the surface-modified implanted materials preventing the biomaterial-centered infection (BCI). [Copyright &y& Elsevier]

There are a variety of silkworms and silk fibroins produced by them. Silks have many inherent suitable properties for biomaterials. In this paper, a novel silk-like hybrid protein, [DGG(A)12GGAASTGRGDSPAAS]5, which consists of polyalanine region of silk fibroin from a wild silkworm, Samia cynthia ricini, and cell adhesive region including Arg-Gly-Asp (RGD) sequence, derived from fibronectin, was designed and produced. The genes encoding the hybrid protein were constructed and expressed in Escherichia coli. The main conformation of the polyalanine region, that is, either α-helix or β-sheet, could be easily controlled by treatment with different acidic solvents, trifluoroacetic acid or formic acid, respectively. This structural change was monitored with 13C CP/MAS NMR. Higher cell adhesive and growth activities of the hybrid protein compared with those of collagen were obtained. [Copyright &y& Elsevier]

Stable energy storage materials have become the research focus today. Coaxial electrospinning can prepare core-sheath nanofibers loaded with phase change materials (PCMs). This method requires the sheath solution have good spinnability and encapsulation ability. Suitable solutions can be prepared by the thermal cross-linking method to improve the properties of nanofibers. Choose hexamethylene diisocyanate (HDI) and β-cyclodextrin (β-CD) as cross-linking agents to adjust the performance of polyvinyl butyral (PVB)/N, N-dimethylformamide (DMF) solution. The adjustment of β-CD addition amount and thermal cross-linking time prepared the best sheath solution as PVB/50CD/HDI. The latent heat of nanofibers prepared by using this sheath solution could be as high as 137.05 J/g. In the meantime, the properties of nanofibers in thermal decomposition, mechanical strength, and elongation rate were also improved. The thermal cycle test proved the good stability of core-sheath nanofibers. This work lays the foundation for the further development of temperature-regulating fibers with high latent heat and performance. [Display omitted] • The core-sheath nanofibers with high latent heat were successfully prepared. • The thermal cross-linking has a good auxiliary effect on coaxial electrospinning. • It has good applications in energy storage systems and thermal regulating garments. [ABSTRACT FROM AUTHOR]

P-aminophenol is a hazardous environmental pollutant that can remain in water in the natural environment for long periods due to its resistance to microbiological degradation. In order to decompose p-aminophenol in water, manganese oxide/polytetrafluoroethylene (PTFE) hollow fiber membranes were prepared. MnO2 and Mn3O4 were synthesized and stored in PTFE hollow fiber membranes by injecting MnSO4·H2O, KMnO4, NaOH, and H2O2 solutions into the pores of the PTFE hollow fiber membrane. The resultant MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were characterized using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermal analysis (TG). The phenol catalytic degradation performance of the hollow fiber membranes was evaluated under various conditions, including flux, oxidant content, and pH. The results showed that a weak acid environment and a decrease in flux were beneficial to the catalytic degradation performance of manganese oxide/PTFE hollow fiber membranes. The catalytic degradation efficiencies of the MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were 70% and 37% when a certain concentration of potassium monopersulfate (PMS) was added, and the catalytic degradation efficiencies of MnO2/PTFE and Mn3O4/PTFE hollow fiber membranes were 50% and 35% when a certain concentration of H2O2 was added. Therefore, the manganese oxide/PTFE hollow fiber membranes represent a good solution for the decomposition of p-aminophenol. [ABSTRACT FROM AUTHOR]

We successfully prepared a Mo 0.2 Co 0.8 P nanowires growing vertically on carbon cloth through hydrothermal and phosphorization processes. This work provides a feasible way for the preparation of non-precious metal electrocatalysts. [Display omitted] • Mo 0.2 Co 0.8 P/CC nanowire arrays was prepared via hydrothermal and low-temperature phosphorization methods. • Mo 0.2 Co 0.8 P/CC possesses outstanding HER activity and strong stability in both 0.5 M H 2 SO 4 and 1 M KOH. • The introduction of Mo atoms lead defects and distortions on the material surface. • The strong synergistic effect between Co and Mo atoms. Exploring an efficient non-noble metal catalyst for hydrogen production by electrolysis of water is one of the effective ways to solve energy shortage and environmental problems. Herein, we report a Mo 0.2 Co 0.8 P nanowires based on carbon cloth (Mo 0.2 Co 0.8 P NWAs/CC) as an efficient HER catalyst in wide-range pH, via facile hydrothermal and phosphorization methods. This Mo 0.2 Co 0.8 P NWAs/CC exhibits the outstanding electrocatalytic performance with low overpotentials of 60 and 66 mV at 10 mA cm−2 and small Tafel slopes of 69.5 and 78.3 mV dec−1 in acidic and alkaline solution, respectively. Moreover, the long-term stability of Mo 0.2 Co 0.8 P NWAs/CC also presents excellent for 50 h at η 10. The superior electrochemical properties of Mo 0.2 Co 0.8 P NWAs/CC material are attributed to its smaller nanoscale, lattice defects and distortions, and strong synergistic effect between Co and Mo atoms. This work provides an effective electrocatalyst for the water electrolysis process. [ABSTRACT FROM AUTHOR]

COVID-19, classified as SARS-CoV-2, is causing an ongoing global pandemic. The pandemic has resulted in the loss of lives and has caused economic hardships. Most of the devices used to protect against the transmission of the novel COVID-19 disease are related to textile structures. Hence, the challenge for textile professionals is to design and develop suitable textile structures with multiple functionalities for capturing viruses, passivating them, and, at the same time, having no adverse effects on humans during the complete period of use. In addition to manufacturing efficient, biocompatible, and cost-effective protective face masks, it is also necessary to inform the public about the benefits and risks of protective face mask materials. The purpose of this article is to address the concerns of efficiency and efficacy of face masks by primarily reviewing the literature of research conducted at the Technical University of Liberec. The main focus is on the presentation of problems related to the specification of aims of face mask applications, mechanisms of capture, durability, and modes of sterilization. The recommendations, instead of conclusions, are addressed to the whole textile society because they should be leading players in the design, creation, and proper treatment of face masks due to their familiarity with the complex behavior of textile structures and targeted changes of structural hierarchy starting from polymeric chains (nano-level) and ending in planar textile structures (millimeter level) due to action by mechanical, physical and chemical fields. This becomes extremely critical to saving hundreds of thousands of lives from COVID-19. [ABSTRACT FROM AUTHOR]

• The tree-like structure of AgNPs/PVDF nanofiber membrane was fabricated by electrospinning. • The AgNPs/PVDF nanofiber membrane with high filtration efficiency and low pressure drop. • The AgNPs/PVDF air filter with durable antibacterial activity against both for S. aureus and E. coli. High filtration performance and antibacterial property have been the main concerns of air filters. In this work, the silver nanoparticles (AgNPs) were produced by liquid phase reduction method and were added into polyvinylidene fluoride (PVDF) solutions at a ratio of 0.2%, 0.4%, 0.6%, 0.8%, and 1% for electrospinning. Nanofibers with the tree-like structure were fabricated by controlling the processing parameters. Therefore, a tree-like AgNPs/PVDF nanofiber membrane containing AgNPs was successfully developed. The AgNPs solutions were analyzed by UV–vis absorption spectrum to determine the size of AgNPs, and the nanofiber membranes were also evaluated in terms of morphology, structure, hydrophobic property, filtration performance, and antibacterial property. The results showed that the size of AgNPs was approximately 10 nm, the average diameters of branch-like fibers and stem-like fibers were about 30.8 nm and between 90 nm with 140 nm, respectively. The addition of AgNPs did not change the hydrophobic property of the PVDF nanofiber membrane; the filtration efficiency of AgNPs/PVDF nanofiber membrane was 99.95–99.97% and the lowest pressure drop was 137.5 Pa; the bacterial reduction rates (BR) value against for S. aureus and E. coli were kept at a level of higher than 99.6% after exposure to sunlight for two weeks. Therefore, a kind of air filter with high filtration performance and durable antibacterial property was successfully developed by adding AgNPs and by creating tree-like structure fibers. [ABSTRACT FROM AUTHOR]

• Magnetic cellulose nanocrystals hybrids reinforced PCF composites were prepared. • Dipole responsive magnetic/solar driven thermal energy storage of PCF composites have reported. • PCF composite exhibited magnetic or solar thermal energy storage efficiencies of 32.1 and 58.6 %. • The PCF composites showed excellent thermal performance and shape stability. • The PCF composites can be used as an integrated collector for potential fruits dryer devices. The intrinsic intermittence of solar energy raises the necessity for thermal energy storage (TES) systems to balance the contradiction between energy supply and demand energy. This work experimentally provides solid-liquid phase change materials (PCMs) with sufficient storage capacity and discharging rate to offer heating for agriculture products by enhancing heat transfer in phase change fiber composites (PCF). To achieve this, we prepared dipole responsive magnetic/solar-driven PCF composites reinforced with magnetic cellulose nanocrystals hybrids (M CNC). The obtained PCF/ M CNC-5% showed excellent magnetic property with a saturation magnetization (MS) value of 1.3 emu/g and effective latent heat phase change enthalpies of 69.2 ± 3.5 J/g – 83.1 ± 4.2 J/g. More importantly, PCF/ M CNC-5% showed robust high magnetic to thermal energy storage efficiency of 32.5 % and solar light accelerated energy storage efficiency of 58.5 %. These advantages make the PCF composites promising and more desirable for drying and preservation of the fruits and other agriculture products. [ABSTRACT FROM AUTHOR]

• Feasible approach for converting waste vinasse into activated carbon was proposed. • AC had abundant micropores of 0.9613 cm3/g and ultrahigh specific surface areas of 2015 m2/g. • AC displayed superior performance with the maximum adsorption capacity of 2251 mg/g for MB. • Removal efficiency for industrial wastewater reached up to 99%. In this work, a simple and feasible approach for converting waste vinasse generated from the alcohol industries into high value-added activated carbon (AC) was proposed. The obtained AC possessed abundant micropores with micropore volume of 0.9613 cm3/g and ultrahigh specific surface areas (2015 m2/g), indicating prominent adsorption capacity. The adsorption ability of AC to cationic methylene blue (MB) was investigated systematically. The resultant AC exhibited superior adsorption ability to MB with a maximum amount of 2251 mg/g, derived from its excellent pore textural features and abundant surface O-containing functional groups. Moreover, AC showed excellent removal efficiency for treating industrial polyacrylonitrile wastewater with 99% removal within 60 min. Our results provide great inspirations in solid waste treatment and their high value-added transformation, meanwhile exploit a promising application of AC for practical wastewater purification. [ABSTRACT FROM AUTHOR]

• In-situ synthesis of cuprous oxide (Cu 2 O) on cotton and coating with nanocellulose, the Cu 2 O crystal structures was ideal octahedron and not easy to ditch. • COCO-5 exhibited high photocatalytic degradation of dyes, and the catalytic degradation process was monitored by comprehensive technical tests. • COCO-5 exhibited highly effective antibacterial properties against Staphylococcus aureus and Escherichia coli. • COCO-5 maintained high stability after multiple photocatalytic degradation of dyes or antibacterial tests, and the mechanical properties of this composite had not decreased. In this study, the cotton fabrics/cuprous oxide-nanocellulose (Cu 2 O-NC) flexible and recyclable composite material (COCO) with highly efficient photocatalytic degradation of dyes and antibacterial properties was fabricated. Using flexible cotton fabrics as substrates, Cu 2 O were in-situ synthesized to make Cu 2 O uniformly grew on cotton fibers and were wrapped with NC. The photocatalytic degradation ability of COCO-5 was verified by use methylene blue (MB), the degradation rate was as high as 98.32%. The mechanism of COCO-5 photocatalysis and the process of dye degradation were analyzed by using electron paramagnetic resonance (EPR) spectrum, transient photocurrent response (TPR) spectrum, Fourier transform infrared (FTIR) spectroscopy and ion chromatography (IC). This study analyzed the complete path from electron excitation to dye degradation to harmless small molecules. Qualitative and quantitative experiments demonstrate that COCO-5 has high antibacterial activity against S. aureus and E. coli , the highest antibacterial rate can reach 93.25%. Finally, the stability of COCO-5 was verified by recycling and mechanical performance tests. The textile-based Cu 2 O functionalized material has photocatalytic degradation and antibacterial properties, and the preparation process is simple and convenient for repeated use, so it has great potential in wastewater treatment containing dyes and bacteria. [ABSTRACT FROM AUTHOR]

Embedding of the functional materials into aerogel powders was realized via the filtration method. In this work, the effect of aerogel on the molecule structure of the embedded polyethylene glycol (PEG) was investigated by dispersing aerogel powders in 20 wt% PEG aqueous solution with subsequent filtration method. The encapsulation of the PEG in the aerogel was characterized by isothermal nitrogen (N 2) adsorption/desorption. The structure of the embedded PEG in the aerogel powders was investigated via SEM-EDS, FE-SEM, FT-IR, XRD. TG-DTA, DSC, and leakage test. It was found that the only physical capillary force worked to adsorb PEG molecules from its solution by the aerogel powders. The BET surface area and the DFT pore volume of the PEG/aerogel powders were reduced obviously when compared with pure aerogel powders. The ability of the pores in the aerogel powders ranging from 14 nm to 16 nm to adsorbing the PEG molecules from the water system was weak. The crystallinity of the PEG was significantly reduced because of the limited space for crystal growth, and the decomposed temperature and thermal capacity decreased correspondingly. Image 1 • Selective adsorption of PEG by pores in aerogel. • Space limitation of PEG crystal growth in aerogel. • Stable thermal property of PEG/aerogel powders. [ABSTRACT FROM AUTHOR]

• Synthesis of bimetallic silver-gold NPs was realized in a cellulose dope. • The dissolved cellulose played as reductant and support matrix for the NPs. • Structure of the NPs was facially tuned by adjusting the feeding operations. • Correlation of bioactivity with nanostructure of the NPs was investigated. • Flexible cellulose decorated with the NPs endowed its efficient SERS activity. Introducing functional metal nanoparticles (NPs) into flexible substrate is being increasingly attempted to expand their application. Here, we extend the synthesis of cellulose to its unmodified dope achieving freestanding nanocomposite decorated with bimetallic Ag-Au NPs through the one pot reaction. In the procedure, cellulose chain not only acts as a reducing agent but also a biocompatible support for NPs with a mean size of 7.9–9.7 nm. Meanwhile, changing the addition order of Ag+ and AuCl 4 − generated different atom arrangement in the bimetallic NPs. Moreover, the correlation of bioactivity to NP atom arrangement was studied. The result revealed that the nanocomposite containing NPs with an ultrathin Ag-rich outermost shell around an Au-rich core showed better bactericidal ability while lower cytotoxicity. In addition, the nanocomposite exhibited a sensitive SERS property for determination of R6G with a high enhancement factor of 108. [ABSTRACT FROM AUTHOR]

In recent years, shape memory polyurethane (SMPU) as a smart material has been used in various applications owing to its desirable shape memory effect and biocompatibility. In this study, unidirectional SMPU nanofibers are innovated by electrospinning to clarify the mechanical and shape memory properties with nanofiber directions. The results showed that when the nanofiber alignment degree is 0° (parallel to the tensile direction), the aligned SMPU nanofibers achieved the obvious improvement of tensile strength (increased to 135%) and elastic modulus (increased to 313%), compared with the random SMPU nanofiber. Moreover, the developed aligned nanofibers exhibited good ability against stress relaxation and creep under constant strain or constant stress conditions in cyclic loading. The aligned SMPU nanofibers with a 0° alignment degree exhibited excellent shape memory properties with shape recovery rates larger than 93% and shape fixity rates larger than 90%, and a dramatic increase of shape recovery stress. • The aligned shape memory polyurethane (SMPU) nanofibers are developed with different alignment degrees. • High performance of shape memory and recovery property is obtained by the aligned SMPU nanofibers. • The relationships between shape fixity, shape recovery ratio and nanofiber alignment are investigated systemically. • Obvious improvement of mechanical properties with 0° nanofibers is identified. • The mechanism of shape memory effect with aligned nanofibers are clarified. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) can efficiently degrade stubborn organic pollutants via advanced oxidation process. However, it is essential to find ways to shape MOFs if its promise of practical application is to be realized. Herein, we develop a Zeolitic Imidazolate Framework-67 (ZIF-67)@cellulose aerogel (denoted as ZIF-67@CA) by a facile doping method. The strategy enhances actual macroscopic shape ability and external hierarchical porosity. Cellulose can provide mechanical flexibility to shape MOFs and promote recycle efficiency after water treatment. The novel doping method increases the loading and dispersibility of ZIF-67, which further increases the potential for the degradation of organic pollutants. ZIF-67@CA can take advantage of the accessible surface area and metal catalytic sites of ZIF-67 to activate peroxymonosulfate (PMS) efficiently and promote its degradation of p-nitrophenol (PNP) and tetracycline hydrochloride (TC). The degradation rate of organic pollutants is up to 80% within only 20 ​min. Furthermore, ZIF-67@CA exhibits excellent pH stability and recyclability so that it can be reused in harsh environments. Therefore, the low-cost and environmental-friendly production method can effectively recycle high-performance MOFs and expand its applications in a wider range of fields. Facile doping method is developed to fabricate the ZIF-67@CA. The strategy can effectively disperse MOFs uniformly. The ZIF-67@CA combines the degradation performance of MOFs and the shape ability of aerogels, which can effectively improve the degradation performance. The degradation mechanism shows that ZIF-67@CA can effectively purify organic pollutants in water. The strategy can be applied to various MOF catalysts in wastewater treatment and thereby expanding their application in a wider range of fields. Image 1 [ABSTRACT FROM AUTHOR]

• Supermagnetic hybrids were successfully synthesized by using CNCs as templates. • Synergistic reinforcing effect of CNCs and Fe 3 O 4 on PHBV performances were observed. • M CNC hybrids can be used as an indicator to detect water vapor. • M CNC reinforced nanocomposites offer a real-time monitoring method for water vapor. • The nanocomposites show great potentials in bioactive and smart packaging materials. In this work, cellulose nanocrystals (CNCs) incorporated with supermagnetic iron oxide nanoparticles (Fe 3 O 4 NPs) as (M CNC) hybrids by the co-precipitation method have developed. High-performance nanocomposite films consisting of poly(3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) and M CNC hybrids have prepared through a simple solution casting method. The addition of CNCs in M CNC-5% hybrids improved the surface hydrophilicity of PHBV, and displayed a reduction in water vapor permeability by 68.1 %, compared with pristine PHBV. The results prove that the addition of M CNC hybrids can be acted like a sensor to detect voltage change of the nanocomposites as functions of water vapor. The existence of CNCs in the M CNC-5% hybrids caused an increase in tensile strength and Young's modulus by 74.6 % and 120.2 %, respectively. The addition of CNCs could enhance cell-matrix interactions and thus cytocompatibility of PHBV nanocomposites. The PHBV/ M CNC-5% exhibited saturation magnetization (Ms) values of 1.5 emu g−1 and displayed almost a regular and operative voltage response signal with real-time monitoring of water vapor. This work provides sustainable smart packaging materials with high sensitivity for water vapor and excellent biocompatibility. [ABSTRACT FROM AUTHOR]

It is of great significance to capture radioiodine from nuclear-related activities. Herein, We fabricated two kinds of hybrid aerogels composed with bimetal Hofmann-type metal-organic frameworks (Co–Fe)II(pz)[NiII(CN) 4 ] and cellulose aerogels by in-situ growth and doping method (named CoFe@CA-IS and CoFe@CA-D, respectively). The hybrid aerogels possessed excellent iodine adsorption performance. The addition of (Co–Fe)II(pz)[NiII(CN) 4 ] increased the porosity of the hybrid aerogels. The porosities of CoFe@CA-IS and CoFe@CA-D were reached 86.7% and 87.8%, respectively, which are higher than pure cellulose aerogels. Furthermore, the doping method provide a significant improve of adsorption performance. The equilibrium adsorption capacity of CoFe@CA-D reached 457.99 mg g−1 and the equilibrium adsorption capacity of CoFe@CA-IS was 194.34 mg g−1. In addition, the hybrid aerogels showed excellent recycle ability, the equilibrium adsorption capacity of CoFe@CA-IS and CoFe@CA-D remained 81% and 91% after 5 cycles. The results suggested that this metal-organic framework@cellulose hybrid aerogel showed great potential in iodine treatment and could be applied in a wide field. A metal-organic framework@cellulose aerogel was synthesized and exhibited outstanding adsorption performance for iodine. Image 1 • Bimetal Hofmann-type MOFs are developed and (Co–Fe)II(pz)[NiII(CN) 4 ] shows the excellent iodine adsorption performance. • Two type of hybrid aerogels are successfully fabricated by in-situ growth and doping method. • CoFe@CA-D shows excellent iodine adsorption performance and the equilibrium adsorption capacity remained 91% after 5 cycles. [ABSTRACT FROM AUTHOR]