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In order to effectively improve the afterglow properties of CaAl2O4:Eu2+,Nd3+ phosphors, a series of Ca0.982–xAl2O4:0.012Eu2+,0.006Nd3+,xGd3+ (x = 0,0.012,0.024,0.036,0.048,0.060 mol) phosphors were prepared by a high-temperature solid-phase approach. Crystalline composition and microstructure were characterized by XRD, TEM, HRTEM, and XPS, luminescence properties were systematically analyzed by fluorescence spectra, afterglow decay curves and TL glow curve. Results show that all of Ca0.982–xAl2O4:0.012Eu2+,0.006Nd3+,xGd3+ phosphors belong to monoclinic CaAl2O4, without other cystalline phase. The blue emission at 442 nm is observed, which is assigned to the 4f65d →4f7 transition of Eu2+ ions. Doping with appropriate amount of Gd3+ ions (x = 0.036mol) significantly improves the afterglow properties of phosphors, but the excessive doping of Gd3+ induces the fluorescent quenching. The doping of moderate Gd3+ changes the traps states, the trap depth varies from 0.598 to 0.644 eV and the trap concentration is also greatly improved, thus significantly improving afterglow performance.

Rational design of earth-abundant transition metal oxides catalysts is highly desirable for developing sustainable chemical processes. Herein, we demonstrate a prospective interstitial nitrogen engineering for fabricating oxygen vacancies (OVs)-rich nitrogen-doped-MnxCo3−xO4 (N-MnxCo3−xO4) oxide catalyst, in which the ratio of OVs concentration of N-MnxCo3−xO4 to Mn species is as high as 1:1, according to the characterizations of X-ray absorption (XAS) and X-ray photoelectron (XPS) spectroscopies. The promising strategy of interstitial nitrogen engineering through lattice distortion caused by the Jahn-Teller effect can significantly increase the amount of interstitial nitrogen. The resulting catalyst enables an additive-free aerobic dehydrogenation coupling of aromatic amine to afford azo compounds with > 99% yield and > 99% selectivity at 60 °C. We observed the superb catalytic activity is promoted by the enhanced oxygen mobility in OVs, which were created by the interstitial nitrogen in the catalyst matrix. The presence of interstitial nitrogen in transition metal oxides in this study shows how the manipulation of catalyst matrix can increase the OV sites to promote aerobic oxidation reaction.

Through adjusting the pH of the silver ammonia solution (Ag(NH3)2OH), different microstructure of silver phosphate (Ag3PO4) was prepared via simple precipitation method. The effect of pH on the mic...

AgBr/BiVO4 photocatalysts with heterojunction structures were prepared using a hydrothermal method. To analyse phase composition and microstructure, samples were characterised by X-ray diffraction ...

Condensation of 2-amino-phenols with carboxylic acid derivatives has been practically used for the production of benzoxazoles, wherein the homogeneous catalytic system including strong acids and da...

In this study, AgBr/Ag2CO3 heterojunction photocatalysts were synthesized by an in␣situ growth method under different pH conditions. The crystal phases, microstructure, visible light absorption, and photocatalytic performance of AgBr/Ag2CO3 heterojunctions were characterized in detail. The results showed that AgBr/Ag2CO3 heterojunctions could enhance photocatalytic activity, compared with pure AgBr and Ag2CO3. In addition, pH conditions in the synthetic process cause a distinct change for photocatalytic activity of AgBr/Ag2CO3 heterojunctions because of the influence on the crystallinity. The AgBr/Ag2CO3 heterojunction synthesized at pH = 9 had the highest photocatalytic activity, and the degradation rate of rhodamine B (Rh B) solution was 98.93% within 20 min. Furthermore, the synthesis mechanism and photocatalytic mechanism were both analyzed.

Tomatoes are rich in nutrients, yet they have a short shelf life and are prone to decay due to bacterial invasion. Polysaccharides extracted from Osmunda japonica (Thunb) were briefly characterised. The inhibitory effect of polysaccharides on nine kinds of common spoilage and pathogenic bacteria in tomatoes stored postharvest was studied, and the polysaccharides had broad‐spectrum antibacterial and antifungal activities against many tested strains. The minimum inhibitory concentrations (MICs) and the minimum bactericidal (fungicidal) concentrations (MBCs) were determined, and the lowest MBC against Bacillus cereus was 0.15 g L⁻¹. Various concentrations of an O. japonica (Thunb) polysaccharide (OP) solution were sprayed onto ordinary preservation paper, which then distinctly maintained tomato freshness. OP delayed vitamin C (VC) and titratable acid decreases and increased respiratory intensity in a dose‐dependent manner, reducing malondialdehyde accumulation. The tomatoes could be stored for 30 day at 25 ± 1 °C. OP has potential as a safe, nontoxic natural plant preservative.

Oxygen delignification presents high efficiency but causes damage to cellulose, therefore leading to an undesired loss in pulp strength. The effect of ionic liquid pretreatment of [BMIM][HSO4] and [TEA][HSO4] on oxygen delignification of the eucalyptus kraft pulp was investigated at 10% IL loading and 10% pulp consistency, after which composition analysis, pulp and fiber characterizations, and the mechanism of lignin degradation were carried out. A possible dual effect of enhancing delignification and protecting fibers from oxidation damage occurred simultaneously. The proposed [TEA][HSO4] pretreatment facilitated lignin removal in oxygen delignification and provided fibers with improved DP, fiber length and width, and curl index, resulting in the enhanced physical strength of pulp. Particularly, its folding endurance improved by 110%. An unusual brightness reduction was identified, followed by detailed characterization on the pulps and extracted lignin with FTIR, UV, XPS, and HSQC. It was proposed that [TEA][HSO4] catalyzed the cleavage of β-O-4 bonds in lignin during the oxygen delignification, with the formation of Hibbert’s ketones and quinonoid compounds. The decomposed lignin dissolved and migrated to the fiber surface, where they facilitated the access of the oxidation agent and protected the fiber framework from oxidation damage. Therefore, it was concluded that ionic liquid pretreatment has a dual effect on oxygen delignification.

The thermo-mechanical properties of unidirectional carbon fiber reinforced epoxy-based shape memory polymer (SMP) composites with fiber mass fractions of 16%, 23%, 30%, 37% are evaluated by using three-point bending tests. The SMP composites show temperature-dependent flexural modulus and strength, with one order of magnitude difference between 120 °C and 20 °C. The composites show good shape recovery capability, with measured recovery ratios of more than 93% at 120 °C and 100% after 20 min at that temperature. The recovery stresses increase nonlinearly during reheating; the maximum recovery stress is approximately proportional to the fiber mass fraction. The composites show recovery capability under external loads, with the recovery ratio being inversely proportional to the partial load level. The composites feature good shape memory properties during cyclic loading and unloading at 120 °C. Their loss factors and stiffness losses decrease significantly during the first three cycles, and then stabilize after ten cycles.

Plasmonic heterojunction photocatalysts consisting of silver covered AgBr/BiVO4 structures (Ag@AgBr/BiVO4) were prepared by hydrothermal-photoreduction method. Their phase composition and microstructure were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron and transmission electron microscopies. The photo-generated electron–hole pair recombination rate was characterized by I–t curves and photoluminescence measurements. Visible light absorption range of Ag@AgBr/BiVO4 plasmonic heterojunction was significantly enhanced. Ag@AgBr/BiVO4 showed high efficiency for degradation of rhodamine B (RhB) under wLED light. RhB degraded by ~ 82% during 150 min reaction time. Ag@AgBr/BiVO4 photocatalyst remained constant after 8 cycles indicating its extreme stability. Enhancement mechanism of Ag@AgBr/BiVO4 plasmonic heterojunction photocatalyst is discussed.

Lignin is the renewable source of aromatics in nature, and the conversion of lignin into vanillin is very attractive. However, the vanillin yield is closely related to the resource of lignin and its isolation process, and relatively low yield of vanillin is always obtained from lignin. In order to improve the vanillin yield from lignin, in this work, the relationship between lignin linkages and vanillin yield was explored. Five lignins (kraft lignin, alkali lignin, lignosulfonate, and two enzymatic lignins) and various lignin model compounds (monomers, dimers, and polymers) were characterized by NMR spectroscopy and oxidized to prepare vanillin. Results indicated that the interunit linkages of the lignin had a significant influence on the vanillin yield. The more β-O-4 linkages in lignin, the higher yield of corresponding aldehydes was obtained. It is believed that the vanillin yield can be significantly improved by using lignins with high content of β-O-4 linkages.

In this paper, submicron-sized spherical Sr2MgSi2O7:Eu2+, Dy3+ phosphors were prepared via sol–gel methods and hydrothermal coprecipitation methods. The effect of different preparation methods on the luminescence properties and microstructures were studied using X-ray diffraction, fluorescence spectra analysis, decay curves, scanning electron microscopy, transmission electron microscopy and laser particle size analysis. Results indicate that the average size of the phosphors via sol–gel methods and hydrothermal coprecipitation methods were 0.711 and 0.389 µm, respectively, and their luminous intensities increased by 20 and 80% as compared to phosphors of the solid state methods, respectively.

Long afterglow phosphors of Sr1.956MgSi2O7: 0.004Eu2+, 0.04Dy3+ and Sr1.94MgSi2O7: 0.004Eu2+, 0.04Dy3+, 0.016Er3+ were successfully synthesized via the sol–gel method. The phase compositions and luminescent properties of the phosphors were analyzed by X-ray diffraction (XRD), fluorescence spectra and decay curves. Compared with the undoped phosphor, the crystallinity of Er3+ co-doping phosphors is decreased. Luminescence spectra show the main peak of excitation was 274, 356 nm and the main emission peak was 467 nm. Furthermore, Sr1.94MgSi2O7: 0.004Eu2+, 0.04Dy3+, 0.016Er3+ show excellent luminescent properties, and its initial luminous intensity increased by 1.4 times than Sr1.956MgSi2O7: 0.004Eu2+, 0.04Dy3+. The mechanism of Sr1.94MgSi2O7: 0.004Eu2+, 0.04Dy3+, 0.016Er3+ enhancement has been discussed.

Renewable, cheap and green biomass resources could meet the urgent need for producing graphene quantum dots (GQDs) on a large scale if high quality can be obtained. Here we report the gram-scale synthesis of single-crystalline GQDs derived from lignin biomass via a two-step method. The synthetic processes involve the oxidized cleavage step followed by the aromatic refusion step of alkali lignin molecules. Notably, this approach successively converts the biomass commonly considered as waste into a high-valued nanoscale product. The as-prepared single-crystalline GQDs, presenting a hexagonal honeycomb graphene network, are 1–3 atomic layers thick. Due to the bright fluorescence, up-conversion properties, long-term photostability, water solubility and biocompatibility, these high quality GQDs have potential to be excellent nanoprobes for multicolour bioimaging. The utilization of renewable biomass resources paves the way for green, low-cost and large-scale production of high quality GQDs and allows for the development of sustainable applications.

We demonstrate a novel afterglow photocatalytic system consisting of Ag3PO4 and afterglow coating. The afterglow coating include three different coating materials, respectively: (i) Sr2MgSi2O7:0.004Eu2+, 0.06Dy3+ (SMSOED); (ii) Sr4Al14O25:0.04Eu2+, 0.04Dy3+, 0.12Er3+ (SAOEDE); and (iii) SrAl2O4:0.004Eu2+, 0.012Dy3+ (SAOED). The blue (peak wavelength: 467 nm from SMSOED coating) and blue-green (peak wavelength: 485 nm from the SAOEDE coating) afterglows effectively promote the degradation of rhodamine B (RhB) with Ag3PO4 in dark environments. The afterglow photocatalytic effect follows the trend: SMSOED coating > SAOEDE coating > SAOED coating. A possible afterglow photocatalytic mechanism was discussed. This system of Ag3PO4/afterglow coating could be applied for all-weather photocatalytic applications.

This work provided an efficient strategy for degradation of organic pollutants in a bad water environment around-the-clock. In this study, a novel afterglow - catalytic system was developed, comprising Ca0.985Al2O4: 0.01Eu2+, 0.005Nd3+ coating as the light source and Ag3PO4 and Pt/Ag3PO4 as the photocatalysts. The results showed that Ca0.985Al2O4: 0.01Eu2+, 0.005Nd3+ emited a blue-violet long afterglow with the primary peak at 440 nm, which could be effectively absorbed by Ag3PO4 and Pt/Ag3PO4 photocatalysts to achieve photocatalytic function in the dark. The afterglow - catalytic activity was enhenced through modifying Nano - Pt particles on the surface of Ag3PO4. More interestingly, the chemical stability of Ca0.985Al2O4: 0.01Eu2+, 0.005Nd3+ phosphor was improved immensely by coating silicone acrylic emulsion, which could resist strong corrosion from water, acid and alkali solution for a long period.

The effect of glass fiber reinforcement on the mechanical properties and geometrical shape stability during the thermomechanical cycle of the shape memory polymer composite has been investigated. A substantial improvement in the mechanical properties due to glass fiber reinforcement has been realized. However, unexpected deformation has been observed during heating process, particularly in the first thermomechanical cycle. This unanticipated deformation negatively affects the geometrical shape stability of the composite, and as a consequence the geometry preciseness of the structural parts manufactured with shape memory polymer composites will be reduced. In this article, the unanticipated thermal deformation in the shape memory polymer composites during the heating has been observed experimentally, and constitutive relationships to describe this behavior have been developed. Furthermore, an application of a constant tensile load during the heating process on the shape memory polymer composite part was found to be a reliable solution to reduce the thermal distortion effect and improve the geometric stability of the composite. The results showed that developed constitutive relations have shown a good agreement with the experimental results. Furthermore, the proposed applied tensile load has shown significant improvement in the shape memory polymer composite samples’ geometrical shape stability when subjected to a temperature increase.

As a main component of space deployable structure, shape memory polymer composites are exposed to long-term periodic sharp temperature changes. It is necessary to investigate the influence of temperature on strength property of shape memory polymer composites. In this article, a micromechanical strength predication model was developed based on composite bridging model, which was used to define the stiffness matrix and relate the stress increment to the fiber and matrix. Furthermore, the progressive failure strength of shape memory polymer composites was simulated simply based on the properties of the material and the geometric parameters of the laminates. Comparison of the predictions with the experimental measurements was carried out. In general, the overall correlation between the theory and the experiments was reasonable. Furthermore, the model has been applied to predict the transverse strength, axial strength, and in-plane shear strength of different composite laminates (fiber content and ply angle) at different temperatures.

In this study, Sr2MgSi2O7:Eu2+,Dy3+ long-afterglow luminescent materials have been successfully prepared via sol-hydrothermal method. The sample shows good crystallinity and optical properties. The sintering time and sintering temperature have great impacts on the crystallization process and luminescence properties. Further, adding of H3BO3 has been found to be good for formation of Sr2MgSi2O7:Eu2+,Dy3+ and appropriate amount of H3BO3 addition helps to improve the performance of the sample afterglow. Crystallization of the samples can be improved by changing the sintering system and method.

In this study, the afterglow properties of Sr 4 Al 14 O 25 :Eu 2+ , Dy 3+ was successfully improved and the absorption in the visible region (>400 nm) was increased using co-doped Er 3+ ions, thus facilitating the application of Sr 4 Al 14 O 25 :Eu 2+ , Dy 3+ in daylight environment. A series of Sr 3.88−x Al 14 O 25 :0.04Eu 2+ , 0.08Dy 3+ , xEr 3+ (x = 0, 0.04, 0.08, 0.12, 0.16, and 0.20) phosphors were prepared using a conventional high-temperature solid-phase method; their structures were characterized by XRD, TEM, HRTEM, FT-IR, and XPS. The luminescence properties, with excitation at 275 nm and 360 nm, were systematically compared and analyzed by fluorescence spectra, afterglow spectra, and afterglow decay spectra. Interestingly, although the Er 3+ doping slightly affected the crystal structure of Sr 4 Al 14 O 25 :Eu 2+ , Dy 3+ phosphor, the luminescent properties of phosphors were affected to a large extent. After the Er 3+ doping, the emission peak of Eu 2+ at 485 nm split into three peaks at 481 nm, 492 nm, and 529 nm. An appropriate Er 3+ doping significantly enhanced the afterglow performance of the phosphors, whereas excessive Er 3+ doping caused concentration quenching. The absorption in the visible region (>400 nm) increased with Er 3+ doping, which was more suitable for the application of Sr 4 Al 14 O 25 :Eu 2+ , Dy 3+ in daylight environment. The initial afterglow intensities with 360 nm excitation were higher than those with 275 nm excitation, whereas the afterglow time of the former was slightly shorter than that of the later. The one-dimensional and two-dimensional lattice fringe phase of the local particles can be observed clearly from HRTEM of flaky-shaped Sr 3.76 Al 14 O 25 :0.04Eu 2+ , 0.08Dy 3+ , 0.12Er 3+ particle, which was rare in the previous reports. Moreover, the preliminarily enhancing mechanism of Er 3+ on the luminescent properties of Sr 3.88 Al 14 O 25 :0.04Eu 2+ , 0.08Dy 3+ phosphor was analyzed.

Emerging flexible supercapacitors have motivated tremendous research interest in portable energy devices. However, challenges still exist in the pursuit of cheap and renewable electrode materials. Herein, a metal-free and flexible supercapacitor was fabricated based on lignosulfonate functionalized graphene hydrogels (LS-GHs). The supercapacitor shows comparable or even higher performance than reported transition metal based pseudocapacitive supercapacitors, which can be attributed to the reversible redox charge transfer of quinone groups in lignin. It presents an impressive specific capacitance of 432 F g−1 in an aqueous electrolyte, which is nearly 2 times higher than that of a pure graphene hydrogel (238 F g−1). Moreover, the device exhibits high rate capability (81.0% capacitance retention at 20 A g−1) and cycling stability (90.0% capacitance retention over 10 000 cycles). The resulting LS-GH electrodes are further fabricated into a flexible solid-state supercapacitor using H2SO4–polyvinyl alcohol (PVA) gel as the electrolyte. The integrated flexible device not only maintains high capacitive performances (408 F g−1 at 1 A g−1, 75.4% capacitance retention at 20 A g−1 and 84.0% capacitance retention over 10 000 cycles), but also exhibits excellent mechanical flexibility. This work paves the way to develop flexible energy devices based on metal-free, renewable and low-cost biomass resources.

In this study, Ag3PO4@holmium phosphate (HP) composite photocatalysts were first prepared by silver-ammonia-solution-assisted solution co-deposition. During co-deposition, Ag3PO4 particles were encapsulated by a flocculent amorphous substance layer of HP, affording a Ag3PO4@HP core–shell heterojunction structure with a Ho/Ag molar ratio of 0.05/2.95. The core–shell structure significantly improved the photocatalytic activity of Ag3PO4. In addition, the photocatalytic mechanism of Ag3PO4@HP was discussed.

In this study, Sr1.94MgSi2O7: 0.02Eu2+, 0.04Dy3+ and Sr1.928MgSi2O7: 0.02Eu2+, 0.04Dy3+, 0.012Nd3+ long afterglow luminescent materials were successfully synthesized via the sol–gel method under reducing atmosphere at 1100 °C for 3 h. No phase structure effect of Sr2MgSi2O7, or significant lattice distortion occurred while a small amount of rare earth ions were doped. Moreover, co-doping Sr2MgSi2O7: Eu2+, Dy3+ with Nd3+ has virtually no effect on the morphology of Sr2MgSi2O7: Eu2+, Dy3+. Co-doping Sr2MgSi2O7: Eu2+, Dy3+ with Nd3+ has also no evident effect on the position of the fluorescence emission peak. However, the applied concentration of Nd3+ co-doping created deeper traps and enhanced the afterglow properties of Sr2MgSi2O7: Eu2+, Dy3+.

To achieve the effective separation of trivalent lanthanides and actinides, a novel NTAAMIDE process based on a non-heterocyclic N-donor NTAamide(n-Oct) extraction system has been developed. It was shown that NTAamide(n-Oct) could extract Am3+ and Eu3+ rapidly to achieve equilibrium within 10 min and has a large loading capacity of 0.75 mol Eu3+/mol NTAamide(n-Oct) in pH = 3.0 HNO3 solution. Meanwhile, relatively high nitrate concentration and low temperature are beneficial for increasing the distribution ratios of metal ions. Further back extraction experiment indicated that both 3.00 mol/L HNO3 and 0.50 mol/L glycollic acid with pH = 4.0 HNO3 could quantitative strip Am3+ and Eu3+ at three stages, while 5 mmol/L TEE-BisDGA was able to selective strip Eu3+. In addition, total organic carbon analysis, FT-IR, 1H NMR, ESI-MS, and extraction measurements revealed that NTAamide(n-Oct) with extremely low solubility in the aqueous phase showed outstanding acid tolerance and irradiation stability. Finally, an enlarged bench test performed by mixer-settler enabled isolating 96.13% Am3+ from macro amount of rare earth elements with decontamination factor of Am3+/Eu3+ as 1320, demonstrating good application prospect for the NTAAMIDE process in the areas of An3+/Ln3+ separation.

Monoclinic BiVO4 photocatalyst was successfully synthesized by hydrothermal method under appropriate temperature. The photocatalytic performance of BiVO4 was improved by calcining at appropriate temperature. The structural and morphological properties of the synthesized BiVO4 photocatalysts were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. It is confirmed that the photocatalytic activity of the prepared catalysts was evaluated by the photodegradation of RhB under visible-light irradiation. BiVO4 calcined under appropriate temperature exhibited higher photocatalytic activity than uncalcined BiVO4 under visible light irradiation because calcination might effectively increases the purity of monoclinic bismuth vanadate.

Effects of CaF2 on the LAS based glass-ceramics and glass-ceramic/diamond composites have been systematically researched. Structure of glass-ceramics was analyzed by XRD and FTIR. And thermal analysis of glass-ceramics was made by TG-DSC and thermal expansion curves. SEM images showed the micro-morphology and structure of the crystals precipitated and the composites. The mechanical properties of the composites were characterized by bending strength and Rockwell hardness. The experiment confirmed the best sintering procedure. Results showed that the addition of CaF2 benefited the glass crystallization and composites mechanical properties. When the content of CaF2 reached 7 wt.%, the nucleation temperature of the glass-ceramic reduced 9 °C and the bending strength and Rockwell hardness of the glass-ceramic/diamond composites improved 27.68% and 29.08%, respectively.

In this study, a series of monoclinic BiVO4 photocatalysts were successfully synthesised by the sol–gel method by varying pH and molar concentration. The structural and morphological properties of the synthesised BiVO4 photocatalysts were characterised by X-ray diffraction and scanning electron microscopy, respectively. The photocatalytic activity of the catalysts was evaluated by the degradation of RhB under visible-light irradiation. The results indicate that at pH = 7, the catalysts showed the best photocatalytic activity, reaching up to 90.9%. Furthermore, at 0.2M concentration, the catalysts showed the best photocatalytic activity, reaching up to 89.4%. The catalysts synthesised at different pH and molar concentrations exhibited different photocatalytic activities under visible-light irradiation because different conditions led to different degrees of crystallinity and grain distributions of monoclinic BiVO4.

Monoclinic BiVO4 photocatalyst was successfully synthesised by sol–gel method under different temperatures and holding times. The structural and morphological properties of the synthesised BiVO4 photocatalysts were characterised by X-ray diffraction and scanning electron microscopy respectively. The photocatalytic activity of the prepared catalysts was evaluated by the photodegradation of RhB under visible light irradiation. It is confirmed that the samples calcined under different temperatures and holding times exhibited different photocatalytic activity under visible light irradiation because calcination under different condition might lead to different purity of monoclinic bismuth vanadate and its grain distribution.

A lignosulfonate-modified graphene hydrogel (LS-GH) for Pb(II) adsorption was synthesized through a one-step method. The three-dimensional (3D) porous architecture of the graphene hydrogel was functionalized by using lignosulfonate with diverse oxygen containing groups. Benefiting from a large specific surface area, multiple porosity and sufficient active sites, the LS-GH adsorbent exhibited ultrahigh adsorption capacity (1210 mg g−1) for Pb(II) removal, which was among the highest of previously reported Pb(II) adsorbents. Importantly, the free-standing and flexible LS-GH can be used as a column-packed device, providing an efficient pathway for the fast removal of Pb(II) with an ultrahigh adsorption capacity of 1308 mg g−1 within 40 min. The high capacity LS-GH adsorbent is low cost, eco-friendly and recyclable, which could be an attractive adsorbent for the purification of wastewater on a large scale.

Energy-storage self-catalysis material that BiVO 4 assembled into porous Sr 2 MgSi 2 O 7 :Eu 2+ ,Dy 3+ was successfully synthesized by the impregnation method. Crystalline phases and microstructure of the energy-storage self-catalysis material were analyzed by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and atomic force microscope. Results indicated that BiVO 4 was assembled into Sr 2 MgSi 2 O 7 :Eu 2+ ,Dy 3+ pores physically. The photocatalysis property of the assembled sample was characterized through degrading the 5 ppm Rhodamine B solution and kinetics property was fitted according to the Langmuir–Hinshelwood formula. Results demonstrated that the assembled compounds exhibited higher photodegradation efficiency than the pure BiVO 4 no matter under the light or dark condition.

Cartilage defects cause joint pain and loss of mobility. It is crucial to induce the chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) by both biological and structural signals in cartilage tissue engineering. Sponge-like scaffolds fabricated using native cartilage extracellular matrix components can induce the BMSC differentiation by biological signals and limited structural signals. In this study, an oriented poly(L-lactic acid)-co-poly(ε-caprolactone) P(LLA-CL)/collagen type I (Col-I) nanofiber yarn mesh, fabricated by dynamic liquid electrospinning served as a skeleton for a freeze-dried Col-I/hyaluronate (HA) chondral phase (SPONGE) containing both structural and biological signals to guide BMSC chondrogenic differentiation. In vitro results show that the Yarn Col-I/HA hybrid scaffold (Yarn-CH) promotes orientation, adhesion and proliferation of BMSCs better than SPONGE. Furthermore, BMSCs seeded on the Yarn-CH scaffold demonstrated a large increase in the glycosaminoglycan content and expression of collagen type II following a 21-day culture.

The work describes a model to predict the elastic constants of unidirectional carbon fiber reinforced shape memory polymer composites (SMPCs) with different fiber volume fractions within the temperature range of 293 K to 393 K. The model is based on a theoretical description of the phase transition of the shape memory polymer (SMP). Two glassy phase volume fraction functions are developed, one based on the Eyring equation, the other based on the normal distribution equation. The longitudinal and transverse moduli, axial and transverse shear moduli, and axial Poisson's ratio are derived by using the glassy phase volume fraction function and modified rule of mixture. The axial Poisson's ratio increases with the temperature increase, while the other four constants decrease nonlinearly with rising temperatures. An inverse identification of the elastic constants at different temperature via numerical and experimental modal analysis from a flat SMPC laminate shows that the model proposed is adequate to describe the temperature dependence of the elastic constants of the laminate.

A tip-loaded deployable truss (TLD truss) with gusseted base and auxiliary support frame has been developed to carry a heavy tip load. This paper presents details in a sequence of material characterization, structure description, finite element analysis, and mechanical experiments. It uses carbon fabric reinforced cyanate-based shape memory polymer composite as the driving source to unfold the packaged truss. The glass transition temperature of the shape memory polymer composite is 195 °C. The recovery moment of the composite increases first and then decreases with the increase of the recovery ratio. Three different structural forms have been compared by modal analysis and swept sine simulations; results show that the TLD truss with a tip load of 1.3 kg has the highest stiffness. Thus it was selected and manufactured to carry out a series of experiments, including swept sine vibration, acceleration and shock testings of the packaged TLD truss, and modal testing of the deployed TLD truss. No damage was observed, indicating the TLD truss has a relatively high stiffness and could withstand the required mechanical environment.

With large spatial deployable antennas used more widely, the stability of deployable antennas is attracting more attention. The form of the support structure is an important factor of the antenna’s natural frequency, which is essential to study to prevent the resonance. The deployable truss structures based on shape memory polymer composites (SMPCs) have made themselves feasible for their unique properties such as highly reliable, low-cost, light weight, and self-deployment without complex mechanical devices compared with conventional deployable masts. This study offers deliverables as follows: an establishment of three-longeron beam and three-longeron truss finite element models by using ABAQUS; calculation of natural frequencies and vibration modes; parameter studies for influence on their dynamic properties; manufacture of a three-longeron truss based on SMPC, and modal test of the three-longeron truss. The results show that modal test and finite element simulation fit well.