Volume 8, Issue 1

Rare earth upconversion nanoparticles (UCNPs) with the superior performance in the biomedical field have attracted great attention. Due to the good light stability, low toxicity, deep tissue penetration and excellent bio-compatibility, UCNPs display great potential for development in the biomedical field. Excellent related reports are increasing year by year, like molecular sensing, bioimaging and therapeutics. In this paper, the preparation, modification, application of upconversion fluorescent nanoparticles and the latest research results in the field of biomedical materials have been reported in detail. Graphical abstract : In this paper, we systematically summarize and describe the preparation, modification, application and latest discovery in biomedical field of rare earth upconversion nanoparticles (UCNP). Due to the good light stability, low toxicity, deep tissue penetration and excellent biocompatibility, UCNPs display superior performance for the development of biomedical field in cancer therapy. Our work will certainly inspire researchers in related fields to create more meaningful upconversion nanomaterials and do more contributions to human cancer treatment research.

We developed a surfactant-free spray coating process to coat commercial cellulose-based paper with carbon nanotubes (CNTs) and prepared paper-CNTs current collectors for Li-ion batteries (LIBs). The paper-CNTs were used as current collectors for replacing conventional aluminum foil. Li-ion batteries assembled using paper-CNTs were coated with LiFePO 4 as the active material and used as cathodes with Li as the anode, and the assembled LIBs showed a high energy density of 460 Wh kg −1 at a power density of 250 W kg −1 . These electrodes were stable even at a current density as high as 600 mA g −1 , and showed cycling stability for ~450 cycles at 150 mAh g −1 . Furthermore, paper-CNTs based electrodes showed ~17% improvement in areal capacity compared to commercial aluminum-based electrodes suggesting that paper-CNTs can readily displace Al foils as current collectors. Summary : Paper based current collectors have been proposed as a cost-effective and simple replacement for aluminum current collectors. This has been achieved by a scalable spray coating of CNTs on printing papers without any surfactants or binders and subsequently testing them as current collectors for Li-ion batteries.

A proper excitation wavelength is much important for the application of surface-enhanced Raman spectroscopy (SERS) in the biochemical field. Here, based on a SERS substrate model with an incident Gaussian beam, we investigate the dependence of the electric field enhancement on the incident wavelength of the excitation laser for popular nanostructures, including nanosphere dimer, nanorod dimer, and nanorod arrays. The results in the present manuscript indicate that both the nanosphere and nanorod dimer present a much broader plasmonic excitation wavelength range extending to the near-infrared region. The enhancement effect of Nanorod arrays is strongly dependent on the incident direction of excitation light. Finally, according to the conclusions above, a SERS substrate consisting of nanocubes based on the SPP eigen-mode is proposed and the electric field enhancement is homogeneous, and insensitive to the polarization of the incident laser. The enhancement factor is not ultrahigh; however, good homogeneousness permits for quantitative detection of lower concentration components in mixtures. Graphical abstract : By investigating the dependence of the electric field enhancement on the incident wavelength of the excitation laser for popular nanostructures, we propose a SERS substrate consisting of Au nanocubes based on the SPP eigenmode. The electric field enhancement is homogeneous, and insensitive to the polarization of the incident laser. Though the enhancement factor is not ultrahigh, good homogeneousness permits for quantitative detection of lower concentration components in mixtures.

BCZT (Ba 0 . 85 Ca 0 . 15 Zr 0 .1Ti 0.9 O 3 ) is a recent class of lead-free ferroelectric material associated with high piezoelectric coefficient, making it suitable to inspire hydroxyapatite (HA)-BCZT ceramics for bone materials. Nano-crystalline hydroxyapatite (HA) synthesized using the hydrothermal route was characterized via FT-IR, Raman spectroscopy, X-ray powder diffraction (XRD), and Scanning Electron Microscopy (SEM). We also rationalized its formation as a function of operating conditions such as dwell time and temperature in this route. The nano-crystalline BCZT powder was synthesized via a sol-gel technique and its structural and morphological characterization were carried out using Raman Spectroscopy, XRD and Transmission Electron Microscopy (TEM). These investigations facilitated the optimization of HA-BCZT compositions and their electrical poling conditions to achieve enhanced piezoelectric effect. The composites (HA-BCZT) sintered at 1350 ∘ C exhibited promising piezoelectric properties. We report the enhanced piezoelectric coefficient (d 33 ) of 7±1 pC/N for 50% HA-BCZT which is significant as compared to that reported in the literature for ~98% BT (barium titanate) -HA composites. We highlight the role of Simulated Body Fluid (SBF) on the intriguing phase-change of Tricalcium Phosphate (TCP) obtained at this sintering temperature, to hydroxyapatite for its essential contribution to promote bone growth. We theoretically support the confirmed in vitro biocompatibility of these composites. Graphical abstract : Novel lead-free biocompatible piezoelectric HA-BCZT nanocrystal composites for accelerated Bone regeneration

Using molecular dynamics simulations, we investigate the movement behavior of double-walled carbon nanotube containing single atom vacancy defect and Stone–Wales defect. The carbon nanotube thermal actuator consists of a short outer tube and a long inner tube driven under temperature gradient. It is found that the presence of these defects introduces resistance of the nanotube systems, which affects their amplitude and speed. The oscillation motion of the outer nanotube is found possible to be produced, which can be achieved by devising proper initial position of the outer tube, the defect type and the temperature gradient. Our results demonstrate the effect of defects on the motion of carbon nanotubes and show that it is possible to control and tune the motion behavior of nanotubes through the introduction of defects.

In the present work, Bisphenol-A Glycidyl Methacrylate / Triethylene Glycol Dimethylacrylate based dental composites filled with 0-30 wt.% silane treated nano-ZnO were fabricated and tested for their dynamic mechanical properties. Samples were kept in each of three different mediums such as cold drink, distilled water and saliva for 7 days. The dynamic mechanical properties such as storage modulus, loss modulus and Tan delta were evaluated and compared for each composite under different conditions. The finding of results indicated that on adding 30 wt.% nano-ZnO, the storage modulus was increased by 109% in case of post cured, 120% in case of cold drink, 125% in case of artificial saliva but decreased by 70% in case of distilled water. The loss modulus was increased by 175% in case of post cured, 30% in case of cold drink, 50% in case of artificial saliva but decreased by 50% in case of distilled water. Further, minimum value of storage modulus was reported in case of distilled water medium followed by cold drink and then artificial saliva. Also, cold drink seems to be better medium than distilled water in terms of dynamic mechanical properties of dental composite. Graphical abstract Variation of storage modulus of sample kept in artificial saliva for 7 days Addition of 30 wt.% nano-ZnO increased the storage modulus by 109% in case of post cured, 120% in case of cold drink, 125% in case of artificial saliva but decreased by 70% in case of distilled water. Addition of 30 wt.% nano-ZnO increased the loss modulus by 175% in case of post cured, 30% in case of cold drink, 50% in case of artificial saliva but decreased by 50% in case of distilled water. Immersion of sample in each medium led to decrease in storage modulus but increase in Tan delta. Further, minimum value of storage modulus was reported in case of distilled water medium followed by cold drink and then artificial saliva. Cold drink seems to be better medium than distilled water in terms of dynamic mechanical properties of dental composite.

To prepare antibacterial fabrics with simple approach, wood pulp/viscose fibers and amino-capped silver nanoparticles (Ag NPs) solution were utilized to form Ag Nps-coated wetlace nonwove fabric. Characterization of the Ag Nps and prepared wetlace nonwoven fabric was performed in virtue of TEM, UV-vis, XRD, ICP-AES, FESEM, EDS mapping and antibacterial test. FESEM and EDS characterizations demonstrated the hierarchical and uniform coating of high-density Ag NPs on wood pulp fibers, and antibacterial test indicated the excellent antibacterial activity of prepared wetlace nonwoven fabric.

Nano cement additive using a hybrid of graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) combines the excellent affinity of GO and the superior mechanical properties of MWCNTs. Ultrasonication is the key process to disperse the GO/MWCNTs and further optimizes the pore structures of cement-based pastes. Fractal dimension can effectively and quantitatively characterize the pore structures of cementitious composites. The present study investigates the fractal dimensions of pore structures of GO/MWCNT-OPC pastes under power- and time-controlled ultrasonication based on the mercury intrusion porosimetry (MIP) tests data. The finding of this study shows that comparing to calculating the fractal dimension of the overall pore size range, assessing the variations of fractal dimension of individual pore size range is more effective in evaluating the pore characteristic. The fractal dimension of larger capillary pores D>104nm$$\left( {{D}_{>{{10}^{4}}nm}} \right)$$can be use to describe the change of pore structure of GO/MWCNT-OPC pastes under ultrasonication treatment with sufficient accuracy as higher value of D>104nm$${{D}_{>{{10}^{4}}nm}}$$indicates better pore characteristics. The fractal dimension change trend of mesopores is always opposite to that of bigger capillary pores. Modest increment in both power- and time-controlled ultrasonication seems to result in the increase of the fractal dimension of capillary pores and lead to better reinforcement effects. Prolongation of ultrasonication time slightly influences the pore structure of the specimens, while nano cement additives exposed to excess ultrasonication power fail to afford adequate reinforcing effect and finally cause the deterioration of the pore structures. The findings of this study can provide helpful information of GO/MWCNT-OPC pastes and ultrasonication treatment in the future.

In the current investigation, the influence of polyvinyl alcohol (PVA) fibers on flowability and durability of cementitious composite containing fly ash and nano-SiO 2 was evaluated. PVA fibers were added into the composite at a volume fraction of 0.3%, 0.6%, 0.9%, and 1.2%. The flowability of the fresh cementitious composite was assessed using slump flow. The durability of cementitious composite includes carbonation resistance, permeability resistance, cracking resistance as well as freezing-thawing resistance, which were evaluated by the depth of carbonation, the water permeability height, cracking resistance ratio of the specimens, and relative dynamic elastic modulus of samples after freeze-thaw cycles, respectively. The results indicated that addition of PVA fibers had a little disadvantageous influence on flowability of cementitious composite, and the flowability of the fresh mixtures decreased with increases in PVA fiber content. Incorporation of PVA fibers significantly improved the durability of cementitious composites regardless of addition of nano-particles. When the fiber content was less than 1.2%, the durability indices of permeability resistance and cracking resistance increased with fiber content. However, the durability indices of carbonation resistance and freezing-thawing resistance began to decrease as the fiber dosage increased from 0.9% to 1.2%. The fiber reinforced cementitious composite exhibited better durability due to addition of nano-SiO 2 particles. Nano-SiO 2 particle improves microscopic structure of fiber reinforced cementitious composites, and the nano-particles are beneficial for PVA fibers to play the role of reinforcement in cementitious composites.

In order to investigate the effects of chromium on the electrical contact properties of the Al 2 O 3 -Cu/15W composites, vacuum hot-pressing sintering and internal oxidation methods were employed to fabricate the Al 2 O 3 -Cu/15W and Al 2 O 3 -Cu/15W5Cr composites. The microstructure was analyzed by scanning and transmission electron microscopy. The electrical contacts testing was performed using the JF04C testing machine at 30 V DC with 10-30 A current. The effects of Cr on the comprehensive properties, arc erosion morphology and welding force of the electrical contacts were investigated. The mass transfer mechanism was discussed. It was demonstrated that the Al 2 O 3 nanoparticles pinned dislocations. The diffraction spots of the Cu matrix and the γ -Al2O3 disclose an orientation relationship of <103> Cu //<103> γ −Al2O3 ,{020} Cu //{040} γ −Al2O3 . A typical arc erosion morphology, such as needle-like and coral structures was formed, which provides significantly enhanced arc erosion resistance of the contact material. Compared with the Al 2 O 3 -Cu/15W composite, the Al 2 O 3 -Cu/15W5Cr composite has a lower welding force. The two composites present two distinct mass transfer trends before and after 25 A. The final mass transfer direction of the composites is from the cathode to the anode. The Al 2 O 3 -Cu/15W5Cr contacts have less mass change under all testing conditions.

The self-expandable metallic stents have been widely used in tracheobronchial obstruction or fistulation, including the J-shaped and Y-shaped stents, named after the shape of the branch-stem junction of the stent. However, there is scarce data on the mechanical performance of these tracheobronchial stents, which is essential for optimal stent implantation. In this work, eight self-expandable metallic tracheobronchial stents in three types ( i.e ., straight, J-shaped, and Y-shaped), with or without cover, were characterized. The compression resistance of the stems was investigated through both compression and indentation tests. The bending resistance of the branches in the J-shaped and Y-shaped stents was assessed through the bending test. Our results demonstrated that the covered stents exhibited a significantly higher compression resistance and bending resistance than the uncovered ones. The branches had a minimal impact on the compression resistance of the stem. The branch of the J-shaped stent showed a significantly lower bending resistance than the Y shaped one. This work provides a testing framework for the J-shaped and Y-shaped stents,which could shed some light on the optimal design of stent with branches.

To explore the characteristics of nanopores in organic-rich shale, the shale of the Upper Yangtze area under different maturity are studied. Scanning electron microscopy (SEM), low temperature nitrogen experiment (LP-N2-GA) and the Frenkel-Halsey-Hill (FHH) fractal model were used. Results show that the intergranular pores and organic pores are most developed, and the pore size is distributed from a few nanometers to several tens of micrometers. The SEM gray scale images make the pore development characteristics of shale be observed more intuitively. Based on the results of low temperature nitrogen adsorption test and FHH fractal model, the results show the fractal dimension of shale is positively correlated with TOC and quartz, but negatively related to clay minerals and feldspar. There is a good relation between maturity and pore volume.With releasing of pressure, the pore evolution gradually returns to the normal compaction trend, and the pore volume of the shale decrease. Graphical abstract: There are many nano-scale pores in the shale, and the pore characteristics determine the characteristics of shale reservoirs. At the initial stage of sedimentary burial, when Ro is less than 0.7%, the pore volume and specific surface area of the initial shale are large. At the medium maturity stage (0.7%<Ro<1.3%), the pore volume and pores caused by mechanical compaction to some extent. As the degree of thermal evolution deepens to the high maturity stage (1.3% <Ro < 2.6%), the shale is generating large amount of gas. The shale belongs to the low-porosity and low-permeability reservoirs, and the generated oil and gas cannot be effectively transported in a short period of time. The overpressure of the reservoir and the inter-mineral pore characteristics caused by the organic pores and organic acids formed by the hydrocarbon generation are more complicated. When shale is in the stage of over-maturation (Ro>2.6%), as the increase of buried depth, the end of hydrocarbon generation process and long-term pressure release, the under-compacting effect gradually disappear. Porosity evolution gradually returns to normal compaction trend in the shale.

The novel braided composite stent (BCS), woven with both nitinol wires and polyethylene terephthalate (PET) strips, were characterized and compared with the braided nitinol stent in the same weaving pattern. Finite element models simulating the stent compression and bending were developed to quantify its radial strength and longitudinal flexibility. The interaction between the nitinol wires and the PET strips were also delineated. Results showed that the PET strips enforced more constrains on the BCS and thus enhance its radial strength especially at a larger compression load. The longitudinal flexibility of the BCS was less sensitive to the presence of the PET strips. This work suggested that the novel design of the BCS could acquire the advantage of a covered stent without compromising its mechanical performance. The fundamental understanding of the braided composite stent will facilitate a better device design.

Defects and temperature effects on the mechanical properties of hexagonal boron nitride sheet (h-BN) containing randomly distributed defects are investigated by molecular dynamics simulations and the reasons of the results are discussed. Results show that defect deteriorate the mechanical performance of BNNS. The mechanical properties are reduced by increasing percentage of vacancy defects including fracture strength, fracture strain and Young’s modulus. Simulations also indicate that the mechanical properties decrease with the temperature increasing. Moreover, defects affect the stable configuration at high temperature. With the percentage of defect increases the nanostructures become more and more unstable. Positions of the defect influent the mechanical properties. The higher the temperature and the percentage of defect are, the stronger the position of the randomly distributed defect affects the mechanical properties. The study provides a theoretical basis for the preparation and performance optimization of BNNSs.

Polyacrylonitrile (PAN) nanofiber membranes with different concentrations, rotary speeds and four kinds of aligned with fiber orientation of 0 ∘ , 0 ∘ /90 ∘ , 0 ∘ /90 ∘ /+45 ∘ and 0 ∘ /90 ∘ /+45 ∘ /−45 ∘ were prepared via electrospinning technique. The nanofiber membranes were morphologically characterized and mechanically tested. The results showed that nanofibers have uniform structure without any beads when the concentration increased 12wt%. The tensile strength and modulus of PAN nanofiber membranes increase with increasing the concentration. The orientation of nanofibers increases significantly with increasing rotary speed and fabricated nanofibers membrane has best orientation and tensile properties at 2500rpm. Moreover, the tensile properties can be affected greatly by the fiber structure and these decrease significantly with increasing the fiber orientation angle. The results also show that the nanofiber membranes exhibit obvious ductile fracture characteristics. Moreover, shear characteristics become more evident with increasing the concentration, and the failure mode changes from shear feature to flush fracture with increasing the rotary speed. In addition, the failure patterns vary with fiber structure and the main damage is in the form of interlayer delaminating, interface debonding, fibers tearing and breakage of the nanofibers.

Compared with traditional materials, nanomaterial has rich and excellent performance due to the size advantages. If nanotechnology is combined with pavement materials, it is foreseeable that it will have a profound impact on the development of the road. In the study, graphene oxide nanomaterial was added as modifiers to rubber asphalt and its microstructure was characterized. The rheological properties of graphene oxide rubber asphalt and the road performance of asphalt mixture were studied in accordance with the SHRP test. The results showed that graphene oxide could form a dense and stable microstructure with rubber powder and asphalt polymer. As a modifier, it could improve the anti-rutting performance of rubber modified asphalt and was more suitable for heavy traffic. Moreover, it had low sensitivity to temperature and was more suitable for areas with large temperature difference between day and night. The pavement performance of the graphene oxide rubber asphalt mixture had also been greatly improved.

The structural, mechanical and thermodynamic properties of tungsten-based alloys, including W 0.5 Ti 0.5 ,W 0 . 67 Zr 0.33 ,W 0.666 Ti 0.1667 Zr 0.1667 ,W 0.67 Hf 0.33 and W 0.666 Ti 0.1667 Hf 0.1667 , have been investigated in this paper by first-principles calculations based on density functional theory (DFT). The calculated elastic constants and mechanical stability criteria of cubic crystals indicated that all of these cubic alloys are mechanical stable. The mechanical properties, including bulk modulus (B), shear modulus (G), Young’s modulus(E), ratio B/G, Poisson’s ratio, Cauchy pressure and Vickers hardness are derived from the elastic constants C ij . According to calculated elastic modulus and Vickers hardness, the W 0.666 Ti 0.1667 Hf 0.1667 alloy has the greatest mechanical strength. The Vickers hardness of these cubic alloys rank as follows: W 0.666 Ti 0.1667 Hf 0.1667 > W 0.67 Zr 0.33 > W 0.666 Ti 0.1667 Zr 0.1667 > W 0.5 Ti 0.5 > W 0.67 Hf 0.33 . Moreover, calculated ratio B/G, Poisson’s ratio, Cauchy pressure indicated that the ductility of W 0.666 Ti 0.1667 Hf 0.1667 alloy is the worst among these alloys. The ductility of these cubic alloys rank as follows: W 0.67 Hf 0.33 > W 0 . 5 Ti 0.5 > W 0.67 Zr 0.33 > W 0.666 Ti 0.1667 Zr 0.1667 > W 0.666 Ti 0.1667 Hf 0.1667 . What is noteworthy is that both mechanical strength and ductility of W 0.666 Ti 0.1667 Hf 0.1667 are greater than pure W. Finally, Debye temperature, melting point and thermal conductivity have been predicted through empirical formulas. All these results will provide scientific data for the study on new product development of electrode materials.

Hydrophobic silica aerogels (SiO 2 (AG)) was prepared via sol-gel and solvent exchange method under ambient pressure, which could be transformed to hydrophilic after heated under 500 ∘ C. Heat treatment cannot change its structure. SiO 2 (AG) samples were the micro-porous structure formed by numerous fine particles and had high specific surface area, pore size and pore volume. The absorption performance of hydrophobic/hydrophilic SiO 2 (AG) on nitrobenzene, phenol and methylene blue (MB) showed that hydrophobic SiO 2 (AG) exhibited strong adsorption capacity on slightly soluble organic compounds, while hydrophilic SiO 2 (AG) was much more effective on adsorbing soluble compounds, which could be analyzed by the hydrophobic and hydrophilic interaction theory between the adsorbent and adsorbate.Hydrophobic/hydrophilic SiO 2 (AG) adsorption performance for MB is superior to that for phenol, which could be explained via the electrostatic interaction theory.

Mesoporous silica microspheres were prepared by the polymerization-induced colloid aggregation (PICA) and pseudomorphic synthesis methods. The prepared microspheres have high specific surface area and MCM-41 type structure. In the PICA process, acidic silica sol was utilized as silica source and the effect of molar ration (formaldehyde/urea) was investigated. Moreover, the influences of reaction time and temperature were also studied. The specific surface area of porous and mesoporous silica microspheres were 186.4 m2/g and 900.4 m2/g, respectively. The materials were characterized by SAXS, FTIR, SEM, TEM and nitrogen sorption measurements. The prepared silica microspheres were functionalized by (3-Aminopropyl)triethoxysilane and then used to remove the lead from aqueous solution. The result indicates that the grafted silica microspheres have rapid adsorption capacity and good reproducibility. The adsorption data was fitted well with the Langmuir isotherm model, and the maximum adsorption capacities for MCM-41 silica microspheres were 102.7 mg/g.

Copper matrix composites reinforced with 1, 3, 5, 7 vol.% Cu-coated SiC whiskers of consistent orientation (SiC w /Cu) were prepared by powder metallurgy and hot extrusion. The microstructure of composites was investigated by scanning electron microscopy. The SiC whiskers were arranged along the direction of hot extrusion and distributed uniformly. The composites were fabricated into specimens with different whisker orientations, and their electrical conductivity was tested. The effects of SiC whiskers orientation and content on the electrical conductivity of composites were investigated through experiment. Results show that the SiC whiskers content was the major factor affecting the electrical conductivity of the composites. With increasing SiC whisker orientations angel, the electrical conductivity of composites is improved. The electrical conductivity model has been established by taking into account the SiC whiskers content, whisker orientation and microstructure parameters, and the results were in good agreement with experimental data. Graphical abstract : Copper matrix composites reinforced with SiC whiskers of consistent orientation were prepared. The orientation of SiC whiskers changes from 0 ∘ to 90 ∘ , resulting in electrical conductivity anisotropy of composites.

An on-fiber extrinsic Fabry–Perot interferometric (EFPI) vibration sensor based on micro-cantilever beam is proposed and experimentally demonstrated. The micro-cantilever beam, with a cantilever length of 80μm and a cantilever thickness of 5μm, is created perpendicular to the fiber axis by using the femtosecond laser micro-machining technique. The on-fiber vibration sensor has same diameter with that of the single mode fiber. An acceleration sensitivity of 11.1 mV/g@300 Hz in the range of 0.5-5g is demonstrated experimentally. This on-fiber and micro-cantilever beam design allows for the sensor to be smaller size and higher temperature resistance.

In response to the widespread bacterial threat, mechanical bactericidal nanostructures with various morphologies have been reported for years. However, the relationship between morphology and bactericidal properties is still yet to be elucidated due to the lack of a fair comparison under similar density of the nanostructures. For this purpose, an electrical-field assisted hydrothermal growth method were utilized to prepare the ZnO nanoarrays with similar array density (1.9×10 9 rod·cm 2 -2.4 ×10 9 rod·cm 2 ) but gradient morphologies from hexagonal prism, hexagonal prismoid to hexagonal pyramid on stainless steel sheets. Moreover, in dark condition, a bactericidal activity was observed on the ZnO nanoarray surfaces within 30 min contact for both E. coli and S. aureus cells. The bactericidal rate was rapidly enhanced as the average tip width of the nanorods decreasing from 137 to 38 nm. These results suggest that the hexagonal pyramid ZnO nanoarrays have a rapid, efficient and broad-spectrum bactericidal activity, which could contribute to the next-generation aquatic pathogens control strategies.

With the development of electric vehicles, more and more high requirements for the lightweight design on EV body are put forward. This paper aims to study a new structure, aluminum alloy mortise-and-tenon structure, which is used for lightweight EVs. Two new types on aluminium alloy MT-T joint specimens are designed and tested under low-cycle reciprocating loading. And the failure characteristics, hysteretic curve, skeleton curve, restoring force model and energy dissipation curve are obtained by analyzing the experimental data. Moment and rotation angle relationship is conducted by joint geometric deformation and equilibrium relation. Based on theoretical model, a simplified bilinear model has been proposed for engineering calculation. When the beam bending performance is qualitatively analyzed, the theoretical model, simulation model and bilinear model are verified through experiments and finite element method simulations. The results show that mortise-and-tenon T joint main failure modes are plastic deformation caused by the upper contact area squeezed each other and the lower contact area divorced each other. Furthermore, it can be obtained from the theoretical model that MT-T joint deformation process consists of elastic segment and elastoplastic segment. Theoretical model, simulation model and bilinear model agree well with the experimental results. This fruit gives a useful reference to composite material used in EVs.

Zirconium oxide (ZrO 2 ) is the general material in dental area, with natural color, high toughness and strength. Recent years, small blocks of ZrO 2 such as micro/nano powders have been studied and developed widely. Nano scale ZrO 2 , which show simproved mechanical characteristics and superior biocompatibility, are usually incorporated into different applications used in dentistry and tissue engineering. This review provides an overview of nano-ZrO 2 materials and its applications in dentistry. The synthesis of nano-ZrO 2 powders were mainly prepared by coprecipitation, hydrothermal method and sol-gel method. Then different applications of nano-ZrO 2 biomaterials in dental ceramics, implants, radio pacifying agents, basement and tissue engineering fields were briefly introduced.

The standard sample IRB7# of nano-sized carbon black was reated by different methods, including washing by alcohol, toluene, water, the emulsion of toluene and water, and heating. Surface activity of the obtained nanoparticles was measured using inverse gas chromatography. The results showed that the dispersion free energy could be significantly increased after heating. The surface activity of three kinds of industrial carbon black was studied after heat treatment at different temperature. The results indicated that surface activity, iodine adsorption number and nitrogen surface area values of carbon black nanoparticles increased with the increase of temperature. However, the dibutyl phthalate adsorption value maintained nearly constant. The performance test of rubber showed that with the increasing heat treatment temperature of carbon black, 300% modulus of rubber increased before 450°C and decreased after 450°C.

A temperature-dependent intrinsic property of monolayer graphene, the negative Poisson’s ratio (NPR), is investigated in the present study. The classical molecular dynamics (MD) method is employed and the Erhart-Albe hybrid potential, i.e . the combination of the reactive empirical bond order (REBO) and the Tersoff potentials, is used for the graphene sheet in the numerical simulation. In the simulation process, the graphene sheet is assumed to be free standing with in-plane periodical boundary condition and under an ambient temperature up to 1000 K. Our study shows that the graphene NPR is decreased with the increase of temperature. Besides, we also perform the simulation of the graphene negative temperature expansion coefficient (NTEC) as an indirect validation of the present MD model. The characteristics of the nonlinear variations for both the NPR and the NTEC of a pristine graphene sheet are investigated. Our MD results at low temperature (0.1 K) further prove the intrinsic and anisotropic property of NPR for graphene.

This study dealt with geometrically nonlinear transient behaviors of carbon nanotube/fiber/polymer composite (CNTFPC) spherical shells containing a central cutout. A multiscale analysis using the Hewitt and Malherbe model was performed to determine the carbon nanotube (CNT)weight ratios, thickness-radius ratios, thickness-length ratios of CNTs, and cutout sizes. Based on the first-order shear deformation plate theory (FSDT),the Newmark method and Newton-Raphson iteration were used for the nonlinear dynamic solution. The proposed approach in this study has been verified by previous studies. Parametric results showed the significance of a proper CNT ratio and curvature for better structural performance on the nonlinear dynamic behaviors of CNTFPC spherical shells with a cutout.

In the field of low temperature co-fired ceramic (LTCC), it remains a challenge to design the performance of LTCC with low permittivity less than 5. Here, the K 2 O– B 2 O 3 –SiO 2 –Al 2 O 3 composites are prepared without the preparation of prior glass. Meanwhile, the factors of the CaO content on microstructure, phase structure and properties of the composites are considered systematically. The crystal structure measured by X-ray diffraction (XRD) shows that there are quartz and alumina as the crystal phases. The results reveals that the tailoring CaO content benefits sintering densification, low dielectric loss, great mechanical properties and low thermal expansion coefficient. As CaO content increases up to 2.8 wt%, the composites sintered at 850 ∘ C have a dielectric constant of 4.94 and tan δ of 8 × 10 −4 at 1 MHz, thermal expansion coefficient (CTE) of 8.5 ppm/ ∘ C, and flexural strength of 150 MPa. As the mass fraction of CaO increases up to 3.2 wt%, the maximum flexural strength of 173MPa is achieved. The above study provides an effective approach for preparing the novel composites as a promising candidate for LTCC applications.

A study on the large amplitude vibration of doubly curved graphene-reinforced composite (GRC) laminated panels is presented in this paper. A doubly curved panel is made of piece-wise GRC layers with functionally graded (FG) arrangement along the thickness direction of the panel. A GRC layer consists of polymer matrix reinforced by aligned graphene sheets. The material properties of the GRC layers are temperature dependent and can be estimated by the extended Halpin-Tsai micromechanical model. The modelling of the large amplitude vibration of the panels is based on the Reddy’s higher order shear deformation theory and the effects of the von Kármán geometric nonlinearity, the panel-foundation interaction and the temperature variation are included in the derivation of the motion equations of the panels. The solutions for the large amplitude vibration of the doubly curved FG-GRC laminated panels are obtained by applying a two-step perturbation approach. A parametric study is carried out to determine the influences of foundation stiffness, temperature variation, FG distribution pattern, in-plane boundary condition and panel curvature ratio on the natural frequencies and the nonlinear to linear frequency ratios of the doubly curved FG-GRC laminated panels.

The reinforcing effect of graphene oxide (GO) in enhancing the flexural strength and flexural modulus of aramid fiber (AF)/epoxy composites were investigated with GO-AFs at a weight fraction of 0.1-0.7%. The flexural strength and flexural modulus of the composite reached 87.16 MPa and 1054.7 MPa, respectively, which were about 21.19% and 40.86% higher than those of the pure epoxy resin, respectively. In addition, the flexural properties and interfacial shear strength (IFSS) of composite reinforced by GO-AFs were much higher than the composites reinforced by AFs due to GO improved the interfacial bonding between the reinforcement material and matrix.

The catalysts performance degradation is a crucial issue in decay of the polymer electrolyte membrane fuel cell (PEMFC). The effect of Nafion content, dispersity of Pt nanoparticles and selected types of carbon support on the degradation of electrochemical surface area (ECSA) and double layer capacitance (DLC) were experimentally discussed by accelerated stress test (AST). The catalyst with 20wt% Nafion content exhibited better catalyst performance. i.e ., the less DLC and ECSA degradation during AST. Catalysts with well Pt dispersity showed superior %ECSA (the percentage change of ECSA) retention. The heat-treated catalysts exhibited the lowest ECSA and DLC degradation rate due to the larger Pt particle and high carbon corrosion resistance. Moreover, a multi-order model describing the correlation between ECSA and DLC degradation was proposed, providing a vital reference for quantitatively investigating ECSA and DLC degradation in the catalysts with different catalysts structural parameters.

Four different minerals were investigated; hollow spheres of calcium carbonate, platy mica, needle like wollastonite and glassy perlite and characterized via iGC for surface energy, Freeman powder rheology for flow characterization, cyclic uniaxial die compaction for modulus of elasticity and frequency dependent sound absorption properties. Particle surface energy and particle shape strongly affected the packing density of powder beds. In the case of higher porosity and thus lower bulk density, the powders acoustic absorption was higher in comparison with higher packing density materials. Surface energy profiles and surface energy distributions revealed clear convergence with powder rheology data, where the character of the powder flow at defined consolidation stresses was mirroring either the high cohesion powders properties connected with the high surface energy or powder free flowing characteristics, as reflected in low cohesion of the powder matrix.

Significant research has been done in recent decades in the field of the dispersion of carbon nanotubes in aqueous solutions and the reinforcement of ordinary Portland cement (OPC). However, the cementitious mixture, as an alkaline environment, easily leads to the re-agglomeration of dispersed single-walled carbon nanotubes (SWCNTs) and influences their enhancing effects. Humic acid (HA) is a type of natural organic matter which can assist the stabilization of dispersed single-walled carbon nanotubes in cementitious composites. The present study characterizes the influence of HA in stabilizing the dispersion of SWCNTs by means of ultraviolet spectrophotometer tests. The fluidity of fresh cement slurry and mechanical performance of hardened OPC pastes were measured to better illustrate the dispersion of SWCNTs in real cement composites. The results not only reveal that the addition of an alkaline environment to the SWCNT suspensions results in a rapid decrease of the dispersion, but also suggest that the appropriate content of HA (0.12 wt.%) can play a significant role in stabilizing the dispersion of SWCNTs. When the mixed hybrid of SWCNTs and HA with a concentration of HA/c equal to 0.05 wt.% is used, the fluidity of the fresh cement slurry experiences a maximum decline and this mixture content of materials will dramatically increase the compressive and flexural strength by about 31% and 48%, which indicates that more SWCNTs are in a dispersed state under this concentration. SEM images further prove that a suitable HA/c can inhibit the expansion of cracks in the cementitious composites.

This paper attempts to investigate the effect of various parameters on the axial compressive behavior of nano-silica concrete-filled angle steel reinforced GFRP tubular columns. The proposed new composite column consists of three parts: the outer GFRP tube, the inner angle section steel and the nano-silica concrete filled between GFRP tube and angle section steel. Twenty-seven specimens with different nano-silica concrete compressive strength (20MPa, 30MPa and 40MPa), diameter-to-thickness ratio of GFRP tube (20, 25 and 40) and steel ratio (0.008, 0.022 and 0.034) were tested under axial load. The main purpose of this study is to examine the effect of the three parameters on the following: failure modes, deformation capacity, load bearing capacity, ductility and initial stiffness of the new composite column under axial load. It was found that the load bearing capacity and initial stiffness increased as the nano-silica concrete compressive strength of the specimens increased. But the specimens with higher nano-silica concrete compressive strength showed lower deformation capacity than that of the specimens with lower nano-silica concrete compressive strength. The varieties of the steel ratio have no significant effect on the specimens’ axial deformation behavior. Experimental results also showed that both load bearing capacity and deformation capacity increased with the decrease of diameter-to-thickness ratio of GFRP tube. However, diameter-to-thickness ratio of GFRP tube has no significant effect on the initial stiffness of specimens. The confinement coefficient was proposed to better evaluate the confinement effect of GFRP tube on the inner angle section steel reinforced core nano-silica concrete. The confinement effect of GFRP tube on lower strength concrete was better, and the confinement effect reduced as the diameter-to-thickness ratio of GFRP tube increased. The design formulas for the load bearing capacity of the nano-silica concrete-filled angle steel reinforced GFRP tubular columns under axial load were proposed.

The heterogeneity of the lamellar unit (LU) of arterial media plays an important role in the biomechanics of artery. Current two-component (fibrous component and a homogenous matrix) constitutive model is inappropriate for capturing the micro-structural variations in the LU, such as contraction/relaxation of vascular smooth muscle cells (VSMCs), fragmentation of the elastin layer, and deposition/disruption of the collagen network. In this work, we developed a representative volume element (RVE) model with detailed micro-configurations, i.e ., VSMCs at various phenotypes, collagen fibers, and elastin laminate embedded in the ground substance. The fiber architecture was generated based on its volume fraction and orientations. Our multi-scale model demonstrated the relation between the arterial expansion and the micro-structural variation of the lamellar unit. The obtained uniaxial response of the LU was validated against the published experimental data. The load sharing capacity of fibrous component and VSMCs of the LU were obtained. We found that the VSMC could take 30% of the circumferential load when contracted until the collagen fibers were recruited, while this value was less than 2% for the relaxed VSMC. In addition, the contribution of collagen fibers at low stretch levels was negligible but became predominant when straightened in high stretches.Moreover, aging effects by collagen deposition was modeled to estimate the arterial stiffening. It was revealed that the aortic stiffness is mainly controlled by collagen fibers, instead of VSMCs. Our findings could shed some light about the contribution of VSMCs in arterial stiffness which has been under debate in recent years.

Interfacial bonding between the fibers and matrix plays a large role in mechanical properties of composites. In this paper, poly(oxypropylene) diamines (D 400 ) and graphene oxide (GO) nanoparticles were grafted on the desized 3D multi axial warp knitted (MWK) glass fiber (GF) fabrics. The surface morphology and functional groups of modified glass fibers were characterized by scanning electron microscopy (SEM) and fourier transform infrared spectra (FT-IR). Out-of-plane compression properties and the failure mechanisms of composites at different temperature were tested and analyzed. The results revealed that GO nanoparticles were successfully grafted on fibers under the synergistic effect of D 400 . In addition, D 400 -GO-grafted composite possessed the highest mechanical properties than desized composite and GO-grafted composite. Their strength and modulus were improved by 10.16%, 10.06%, 8.92%, 8.75%, 7.76% and 40.38%, 32.74%, 29.85%, 26.98%, 25.16% compared to those of desized composites at 30 ∘ C, 60 ∘ C, 90 ∘ C, 120 ∘ C, 150 ∘ C, respectively. The damage to D 400 -GO-grafted composite was yarns fracture accompanied with fibers breakage, matrix cracking, interface debonding. At higher temperature, interlayer slipping with matrix plasticization was the main failure mode.

Experimental research on circular nano-silica concrete filled stainless steel tube (C-CFSST) stub columns after being exposed to freezing and thawing is carried out in this paper. All of forty specimens were tested in this paper, including nine C-CFSST specimens at normal temperature, 28 short columns of C-CFSST for freeze-thaw treatment and three circular hollow stainless steel stub columns. The failure mode, load-displacement curves, load-strain curves and load-bearing capacity were obtained and analyzed in this paper. The main parameters explored in the test include the number of freeze-thaw cycles ( N =0, N =50, N =75, and N =100), wall thickness ( T =1.0mm, T =1.2mm, T =1.5mm) andnano-silica concrete strength ( f c =20MPa, f c =30MPa, f c =40MPa). The result shows that C-CFSST short columns at normal temperature and subjected to freezing and thawing follow similar failure mode. The effect of freeze-thaw cycles ( N ) of 50 on bearing capacity of C-CFSST column was maximal, and then the influence of N on the bearing capacity of specimens was small when N reached to 75, finally the effect of N on bearing capacity of C-CFSST column was large when N reached to 100. The bearing capacity of C-CFSST columns increases with increasing wall thickness. In addition, the loss percentage of bearing capacity of specimens ( f c =40MPa) for freeze-thaw treatment is maximal, and the loss percentage of bearing capacity of specimens ( f c =30MPa) for freeze-thaw treatment is minimal. According to the test results, this paper proposed a formula to calculate the bearing capacity of C-CFSST short columns for freeze-thaw treatment.

Arc erosion behaviors of TiB 2 /Cu composites with single-scale and dual-scale TiB 2 particles fabricated by powder metallurgy were studied. It was revealed that the dual-scale TiB 2 /Cu composites had fewer structure defects compared with the single-scale TiB 2 /Cu composites, and TiB 2 particles with different size were uniformly distributed in the copper matrix. When the ratio of 2 μm over 50 μm TiB 2 particles is 1:2, the density of TiB 2 /Cu composite is 98.5% and shows best mechanical and thermal properties. The arc duration and energy of TiB 2 /Cu composites increase with the increase of electric current in contact material testing. Compared with the single-scale TiB 2 /Cu composites, the arc erosion of dual-scale TiB 2 /Cu composite with 2 μm+50 μm (1:2) TiB 2 was slighter. The anode bulge area and cathode erosion pit of dual-scale TiB 2 /Cu composite was smaller. The dual-scale TiB 2 particles optimize the microstructure and thermal stability of the composite, which is conducive to alleviating arc erosion. The synergistic effect of different sized TiB 2 particles in the matrix improved the arc erosion resistance of TiB 2 /Cu composite during arcing.

Melanoma is the most lethal dermal tumor, and a high recurrence rate and skin defects are two main serious problems. An antimelanoma material,which effectively inhibits tumor recurrence and possesses excellent biocompatibility, is urgently needed to treat melanoma. In this study, we developed a novel antitumor Yb 3+ [Yb(NO 3 ) 3 ]containing chitosan hydrogel (Yb-CS hydrogel) by dissolving Yb(NO 3 ) 3 and chitosan in acetic acid solution and forming composite hydrogels by a freeze-drying process after adding NaOH to the mixed solution. In vitro studies demonstrated that the Yb 3+ produces effect of inducing cell death in Yb-CS hydrogel. Moreover, we found that the Yb-CS hydrogel inhibited a focal adhesion kinase (FAK)-dependent signaling pathway and induced B-16 cell anoikis. However, the Yb-CS hydrogel was less effective on L929 normal mouse dermal cells. In vivo studies showed that the Yb-CS hydrogel inhibited the recurrence of melanoma in a mouse bare xenograft tumor model. We concluded that the Yb-CS hydrogel could potentially be used in the antimelanoma field, especially in the inhibition of melanoma recurrence.

Both selenium and reduced graphene oxide have low specific capacitance due to their chemical nature. Nevertheless, their specific capacitance could be enhanced by hybridizing Se nanomaterials with reduced graphene oxide via formation of electrochemical double layer at their interfacial area. Therefore, novel Se-nanorods/rGO nanocomposite was successfully synthesized by template free hot reflux route starting with graphene oxide and selenium dichloride. The composite of rGO decorated by Se-nanorods is characterized using X-ray diffractometry (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption– desorption. The unique architecture of the composite exhibits high specific capacitance of 390 F/ g at 5 mV/s scan rate in 1.0 M KOH solution with ~ 90% cyclic stability after 5000 cycles making it very promising electrode material for supercapacitor applications.

Graphene oxide (GO) is a nanomaterial with ultra-high strength, good hydrophilicity, and dispersibility. To study the effect of GO on chloride penetration resistance of recycled concrete, the mechanism of action is investigated. The electric flux method is used to test the chloride penetration in recycled concrete specimens with 0, 0.03%, 0.06%, and 0.09% of GO. The volume change, microscopic pore distribution, and micro-structure morphology are characterized using laser rangefinder, and techniques such as X-ray tomography and scanning electron microscopy. The results show that the "coagulation nodule" effect of GO provides a growth basis for cement hydration,which results in a more uniform distribution of the hydrate microcrystals. It fills the micro-cracks of the recycled concrete, reduces the most probable aperture, increases the number of harmless small apertures, and enhances the volume stability of recycled concrete, thereby improving the chloride penetration resistance, which is important for improving the durability of concrete.

In this study, the effects of polyvinyl alcohol (PVA) fiber content and nano-SiO 2 (NS) on bending resistance of cementitious composites were investigated including bending strength and toughness. PVA fiber contents from 0.6% to 1.5% were added in the composites. The NS contents was 0% and 2% by mass. The water to binder ratio (w/b) was 0.38 for all composites. The specimens were cured for 28 days under 20 ∘ C and relative humidity of 95% before bending test. The results show that the bending strength was improved with PVA fiber content increasing and the maximum bending strength was obtained at PVA fiber content of 1.5%. Although PVA fiber increased bending resistance regardless of NS addition, the optimal content was 1.2%. When the fiber content was less than 1.2%, the bending resistance of cementitious composites increased with fiber content. However, the toughness began to decrease as PVA fiber content increased from 1.2 % to 1.5%.2% NS addition decreased both bending strength and toughness due to the fact that NS was prone to self-desiccation and flock together, resulting in micro crack and strength loss.

Supercapacitor has gained significant attention due to its fast charging/discharging speed, high power density and long-term cycling stability in contrast to traditional batteries. In this review, state-of-the-art achievements on supercapacitor electrode based on carbon materials is summarized. In all-carbon composite materials part, various carbon materials including graphene, carbon nanotube, carbon foam and carbon cloth are composited to fabricate larger specific surface area and higher electrical conductivity electrodes. However, obstacles of low power density as well as low cycling life still remain to be addressed. In metal-oxide composites part, carbon nanotube, graphene, carbon fiber fabric and hollow carbon nanofibers combine with MnO 2 respectively, which significantly address drawbacks of all-carbon material electrodes. Additionally, TiO 2 is incorporated into graphene electrode to overcome the low mechanical flexibility of graphene. In organic active compounds part, conducting polymers are employed to combinate with carbon materials to fabricate high specific capacitance, long-term thermal stability and outstanding electroconductivity flexible textile supercapacitors. In each part, innovation, fabrication process and performance of the resulting composites are demonstrated. Finally, future directions that could enhance the performance of supercapacitors are discussed.

The stiffness of arterial wall in response to cardiovascular diseases has been associated with the changes in extracellular matrix (ECM) proteins, i.e ., collagen and elastin. Vascular smooth muscle cells (VSMCs) helped to regulate the ECM reorganizations and thus contributed to arterial stiffness. This article reviewed experimental and computational studies for quantifying the roles of ECM proteins and VSMCs in mechanical properties of arteries, including nanostructure and mechanical properties of VSMCs and ECMs, cell-ECM interaction, and biomimetic gels/scaffolds induced contractile properties and phenotype changing of VSMCs. This work will facilitate our understanding of how the microenvironments and mechanotransduction impact and regulate the arterial adaptation.

Polymer-based nanoparticles have good solubility, stability, safety, and sustained release,which increases the absorption of loaded drugs, protects the drugs from degradation, and prolongs their circulation time and targeted delivery. Generally, we believe that prevention and control of infectious diseases through inoculation is the most efficient measure. However, these vaccines including live attenuated vaccines, inactivated vaccines, protein subunit vaccines, recombinant subunit vaccines, synthetic peptide vaccines and DNA vaccines have several defects, such as immune tolerance, poor immunogenicity, low expression level and induction of respiration pathological changes. All kinds of biodegradable natural and synthetic polymers play major roles in the vaccine delivery system to control the release of antigens for an extended period of time. In addition, these polymers also serve as adjuvants to enhance the immunogenicity of vaccine. This review mainly introduces natural and synthetic polymer-based nanoparticles and their formulation and properties. Moreover, polymer-based nanoparticles as adjuvants and delivery carriers in the applications of vaccine are also discussed. This review provides the basis for further operation of nano vaccines by utilizing the polymer-based nanoparticles as vaccine adjuvants and delivery systems. Polymer-based nanoparticles have exhibited great potential in improving the immunogenicity of antigens and the development of nano vaccines in future.

Metallic nanoparticles due to their small size and unique physico-chemical characteristics have found excellent applications in various branches of industry and medicine. Therefore, for many years a growing interest has been observed among the scientific community in the improvement of our understanding of the impact of nanoparticles on the living organisms, especially on humans. Considering the delicate structure of the central nervous systemit is one of the organs most vulnerable to the adverse effects of metallic nanoparticles. For that reason, it is important to identify the modes of exposure and understand the mechanisms of the effect of nanoparticles on neuronal tissue. In this review, an attempt is undertaken to present current knowledge about metallic nanoparticles neurotoxicity based on the selected scientific publications. The route of entry of nanoparticles is described, as well as their distribution, penetration through the cell membrane and the blood-brain barrier. In addition, a study on the neurotoxicity in vitro and in vivo is presented, as well as some of the mechanisms that may be responsible for the negative effects of metallic nanoparticles on the central nervous system. Graphical abstract: This review summarizes the current knowledge on the toxicity of metallic NPs in the brain and central nervous system of the higher vertebrates.

In this study, graphene colloids were prepared using the electric spark discharge method (ESDM) with graphite rods (99.9% purity) in deionized water (DW) at a normal temperature and pressure. Five different types of graphene colloids were prepared using an electrical discharge machine (EDM) with five different pulse cycle switching times (T on :T off ) = 10:10, 30:30, 50:50, 70:70, and 90:90 μs. According to the Ultraviolet-visible spectra (UV-Vis) and Zetasizer analysis, the results showed that the 10:10 μs parameter was the most suitable for the preparation of graphene colloids. UV-Vis was also used to detect the concentration of the graphene colloids; a comparison with a graphene oxide (GO) confirmed that this method could be used to calculate the discharge time needed to produce graphene colloids with different concentrations in the ESDM process.

This review is devoted to discuss the unique characteristics of multi-jet electrospinning technique, compared to other spinning techniques, and its utilization in spinning of natural as well as synthetic polymers. The advantages and inadequacies of the current commercial chemical spinning methods; namely wet spinning, melt spinning, dry spinning, and electrospinning are discussed. The unconventional applications of electrospinning in textile and non-textile sectors are reported. Special emphasis is devoted to the theory and technology of the multijet electrospinning as well as its applications. The current status of multi-jet electrospining and future prospects are outlined. Using multi-jet electrospinning technique, various polymers have been electrospun into uniform blend nanofibrous mats with good dispersibility. In addition to the principle of multi-jet electro electrospinning, the different devices used for this technique are also highlighted.

Au@Ag nanoparticles decorated on cellulose paper could be worthful biomedical applications. Electrospinning technique is broadly employed for fabrication of nano and micro size fibers with a variety of biopolymers adding cellulose acetate nanofibers. Evolutions in cellulose research demonstrate that it is an anticipating material for the biomedical application. Nanofibers acquired by electrospinning technique were utilized in various biomedical applications. In this report, electrospinning of cellulose acetate, the solvent choice for cellulose acetate e-spun nanofabrication and decoration of AgNPs including shape and size for antimicrobial activity are argued.

This paper demonstrates a brief review of the research progress of the advanced carbon-based materials for the supercapacitor electrodes. Diverse types of carbon-based electrodes exploited and reported to the literature are summarized and classified into pure carbon electrodes, carbon/metal oxides composite electrodes, carbon/metal oxides/conducting polymers composite electrodes as well as carbon electrodes based on other materials. Pure carbon electrodes are firstly introduced, confirming their merits and shortcomings. To cover the shortage of pure carbon electrodes and further enhances their electrochemical performance, a composite electrode, combined with metal oxides and conducting polymers, is respectively presented. It is worth noticing in this article that combining various materials to form composites has been one main direction to own a positive synergistic effect on the carbon-based electrodes.

Shape memory polymers (SMPs) can be programmed to a temporary shape, and then recover its original shape by applying environmental stimuli when needed. To expands the application space of SMPs, the shape memory polymer composites (SMPCs) were fabricated either to improve the mechanical properties, or to incorporate more stimulus methods. With the deepening of research, the filler arrangement can also be used to reshape the composites from a two dimensional sheet to a three dimensional structure by a strain mismatch. Recently, SMPCs show more and more interesting behaviors. To gain systematic understanding, we briefly review the recent progress and summarize the challenges in SMPCs. We focus on the reinforcement methods and the composite properties. To look to the future, we review the bonding points with the advanced manufacturing technology and their potential applications.

Small Angle X-ray Scattering (SAXS) is an ideal characterization tool to explore nanoscale systems. In order to investigate nanostructural changes of materials under realistic sample environments, it is essential to equip SAXS with diverse in situ capabilities based on the corresponding requirements. In this paper, we highlight the representative experimental setups and corresponding applications of five widely used in situ capabilities: temperature, pressure, stretching, flow-through, and electric field. Additionally, we also briefly introduce other four in situ techniques including humidity, high-throughput, rheology, and magnetic field.

Copper alloys and copper matrix composites have been attracting a lot of attention lately. Their composition design, preparation, and processing directly affect the final performance. In this review, several typical copper alloys, such as Cu-Fe-P, Cu-Ni-Si, and Cu-Cr-Zr are analyzed. The deformation mechanisms, microstructure evolution, and dynamic recrystallization behavior are summarized. In addition, dispersion strengthened copper matrix composites and graphene reinforced copper matrix composites are reviewed.

Transparent electronics has attracted much attention and been widely studied for next-generation high-performance flat-panel display application in the past few years, because of its excellent electrical properties. In display application, thin film transistors (TFTs) play an important role as the basic units by controlling the pixels. Among them, oxide-based TFTs have become promising candidates and gradually replaced the conventional amorphous and polycrystalline silicon TFTs, due to high mobility, good transparency, excellent uniformity and low processing temperature. Even though n-type oxide TFTs have shown high device performance and been used in commercial display application, p-type oxide TFTs with the equal performance have been rarely reported. Hence, in this paper, recent progress and challenges in p-type oxide-based TFTs are reviewed. After a short introduction, the TFT device structure and operation are presented. Then, recent developments in p-type oxide TFTs are discussed in detail, with the emphasis on the potential p-type oxide candidates as copper oxide, tin oxide and nickel oxide. Moreover, miscellaneous applications of p-type oxide TFTs are also presented. Despite this, the performance of p-type oxide TFTs still lags behind, as compared with that of n-type counterparts. Thus, the current issues and challenges of p-type oxide TFTs are briefly discussed.

The solar power is one of the most promising renewable energy resources, but the high cost and complicated preparation technology of solar cells become the bottleneck of the wide application in many fields. The most important parameter for solar cells is the conversion efficiency, while at the same time more efficient preparation technologies and flexible structures should also be taken under significant consideration [1]. Especially with the rapid development of wearable devices, people are looking forward to the applications of solar cell technology in various areas of life. In this article the flexible solar cells, which have gained increasing attention in the field of flexibility in recent years, are introduced. The latest progress in flexible solar cells materials and manufacturing technologies is overviewed. The advantages and disadvantages of different manufacturing processes are systematically discussed.

The paradigm of using phenylboronic acid-decorated polymeric nanomaterials for advanced bio-application has been well established over the past decade. Phenylboronic acid and its derivatives are known to form reversible complexes with polyols, including sugar, diol and diphenol. This unique chemistry of phenylboronic acid has given many chances to be exploited for diagnostic and therapeutic applications. This review highlights the recent advances in fabrication of phenylboronic acid-decorated polymeric nanomaterials, especially focus on the interactions with glucose and sialic acid. Applications of these phenylboronic acid-decorated nanomaterials in drug delivery systems and biosensors are discussed.

In recent years, the addition of nanometer materials to concrete materials has attracted a group of increasing number of scholars’ research interests, and nano-SiO 2 is one of the research hotspots. In this paper, we briefly introduce the influence of nano-SiO 2 on setting time, slump, shrinkage, durability and mechanical properties of concrete. In addition, this review also includes the microstructure measured by scanning electron microscope (SEM) and the content of various hydration products obtained by X-ray diffraction (XRD). The result shows that the setting time of nano-SiO 2 concrete is shortened, the slump is reduced and the shrinkage is improved owing to the high activity and nucleation of nano-SiO 2 . The improvement effect of nano-SiO 2 on concrete is remarkable, especially in the aspect of enhancing the durability of concrete. It should be noted that nano-SiO 2 shows limited improvement in the mechanical properties of concrete. In the end, this literature summary explains the macro performance of nano-silica modified concrete through microstructure.

Fluorinated carbon (CF x ), a thriving member of the carbonaceous derivative, possesses various excellent properties of chemically stable, tunable bandgap, good thermal conductivity and stability, and super-hydrophobic due to its unique structures and polar C-F bonding. Herein, we present a brief review of the recent development of fluorinated carbon materials in terms of structures, properties and preparation techniques. Meanwhile, the applications in energy conversions and storage devices, biomedicines, gas sensors, electronic devices, and microwave absorption devices are also presented. The fluorinated carbon contains various types of C-F bonds including ionic, semi-ionic and covalent C-F, C-F 2 , C-F 3 bonds with tunable F/C ratios. The controllable designing of C-F bonding and F/C ratios play a key role to optimize the properties of fluorinated carbon materials. Until now, the potential issues and future opportunities of fluorinated carbon are proposed. The present review will provide a direction for tuning C-F bonding and F/C ratios, developing a safe and efficient fluorination method and popularizing the applications of fluorinated carbon materials.

The nanoscratch test has been identified as one of the important tools for evaluating the mechanical and tribological properties of materials. This paper reviews the current researches on the nanoscratch test using to characterise the mechanical properties of three typical materials, including thin film, polymer composite and concrete, from the perspectives of the Berkovich indenter, parameter selection, mode selection, and analysis of resulting data. In addition, to provide a deep understanding on the test from different magnitude, a comparison between the microscratch test and nanoscratch test on the evaluation of tribological performance is also provided in this paper. The characterisation by nanoscratch test of two structural samples, in terms of layered film structures (thin film and coating sample) and single layer block structure (polymer composite sample and concrete samples) are also described in this paper, which aims to provides a deep understand on the evaluation the adhesion, tribological and interfacial properties of the typical materials samples by nanoscratch test. Finally, the coefficient of friction and critical load are discussed, which are two important parameters in tribological properties and adhesion properties.

Self-decontaminating cotton fabrics were designed, produced and characterized aiming at the decomposition of harmful molecules namely chemical warfare agents (CWAs) by photocatalysis under day light or indoor illumination. This was achieved through the creation of a hybrid organic-inorganic nanostructured textile composed of a thin layer of TiO 2 nanoparticles (NPs) generated in situ and chemically immobilised on the cellulose chains of cotton fibres. TiO 2 NPs were converted into anatase by a hydrothermal procedure at low temperature around 100°C. The fabrics covered with TiO 2 nanoparticles were examined in terms of their chemical composition, morphology, crystallinity, ageing, robustness and photocatalytic properties. In the whole preparation of the photocatalytic fabrics, only environment-friendly solvents (water or alcohol) were used. One of the important achievements in this work was providing fabrics with suitable photocatalytic activity under visible light. This was reached through plasmonic photocatalysis by generating noble metal nanoparticles (Au, Ag) and/ or their halides (AgBr, AgCl) neighbouring or topping the TiO 2 NPs in the fabrics. The kinetics of degradation of the different systems were analysed and proved that the resulting fabrics could efficiently decompose, under visible light, organic dyes and dimethyl methylphosphonate (DMMP), a CWA simulant. Graphical abstract