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Lanthanide (Ln) metal–organic frameworks (Ln-MOFs) have attracted attention in anti-counterfeiting and white light-emitting diodes (WLEDs) due to their high quantum efficiency, long lifetimes, and characteristic linear spectrum. However, Ln-MOFs have some disadvantages, such as harsh luminescence modulation, low transparency, and poor film formation. In this study, Ln-MOF (Ln = Eu and/or Tb)-modified TEMPO-oxidized cellulose nanofibrils were employed for preparing transparent nanopapers and luminescence modulation. These luminescent nanopapers achieved an excellent light emission color tuning from green, yellow, and red under 365 nm excitation, while 254 nm radiation on these nanopapers only emitted characteristic pink light. Thus, the luminescent nanopapers combined color-tuning and photo-switching properties through the control of Eu³⁺/Tb³⁺ molar ratio and excitation wavelength (λEₓ at 365 and 254 nm), respectively, which greatly improved them for anti-counterfeiting applications. In addition, Ln-MOFs endowed these nanopapers with excellent optical haze (>90%), such that softening of white light from WLEDs was realized in 254 nm-driven UV-LED chips, corresponding white light with good color quality [Commission International de I’Eclairage coordinates, correlated color temperature, and color-rendering index of (0.34, 0.36), 5536 K and 86, respectively].

Separation or purification is one of the difficult problems in the petrochemical industry. To help solve the difficulty of separation or purification for C2H2/CO2 and C2Hn/CH4 in the chemical industry, we synthesized a new metal-organic framework (MOF), [Ni(dpip)]·2.5DMF·H2O (1), by a bipyridyl-substituted isophthalic acid ligand. The MOF includes two types of one-dimensional (1D) tubular channels with different sizes and porous environments. The unique tubular channels lead to not only remarkable gas sorption capacity of C2H4, C2H2, and CO2, but also good selectivity for C2H2/CH4, C2H2/CH4, CO2/CH4, and C2H2/CO2, as demonstrated by single-component sorption isotherm results, ideal adsorbed solution theory calculations, and dynamic breakthrough curves. Grand canonical Monte Carlo (GCMC) simulation reveals preferential adsorption sites in the MOF for CO2, C2H2, and C2H4. The MOF also exhibits an obvious size-selective absorption effect on vapor molecules.

The chiral deformation of a conventional helical actuator is unidirectional in each activation (stimuli-on) process and in each recovery (stimuli-off) process, which means that the twisting direction remains the same regardless of the nature of deformation (either winding or unwinding or helix-inversion). In these cases, a complete stimuli-switching cycle is necessary for the realization of a bidirectional helical deformation process that comprises a reversal of twisting direction. Here, we achieved bidirectional and even multi-directional helical shape evolution in each stimuli-on (or off) process. The strategy relies on, on one hand, asymmetrically crosslinking and/or elongating the two sides of a photocrosslinkable liquid crystal polymer (LCP) monolith, and on the other hand, tailoring the uniaxially aligned polymer strip to form an off-axis mesogen orientation. We obtained a wide variety of helical actuators capable of reversing their twisting directions by only cooling (or heating). The mechanisms of these various chiral deformation-reversal behaviours and the two observed reversals of the twisting direction during cooling have been elucidated.

Developing highly efficient and low-cost electrocatalysts for the hydrogen evolution reaction (HER) in neutral media is crucial but still a significant challenge on account of the sluggish multistep reaction kinetics involved. Theoretically, constructing a metal/metal hydroxide interface with a metal hydroxide acting as a water dissociation promotor and a metal as the subsequent hydrogen adsorption site is expected to accelerate the HER kinetics in neutral media. We found that the intercalation of tungstate into Ni(OH)2 can tune the electronic structure of the Ni/Ni(OH)2 interface, decrease the energetic barrier for the Volmer step, and thus optimize the HER performance of Ni/Ni(OH)2 hybrid. Herein, a heterostructured Ni/Ni(OH)2 nanosheet array on Cu foam is designed and constructed via a simple hydrothermal and subsequent plasma reduction strategy. The HER performance can be further enhanced by assembling tungstate-intercalated Ni/Ni(OH)2 hybrid nanosheets on Cu2O nanotube arrays, exhibiting a low overpotential (39 mV @ 10 mA cm−2) and excellent stability (48 h).

Transition metal phosphides (TMPs) have been reported as efficient pre-catalysts for the oxygen evolution reaction (OER) in alkaline media. In situ generated metal oxyhydroxides on the surface of TMPs serve as real active sites. However, the reconstruction of most of the reported TMPs is incomplete and the active components cannot be fully used. Herein, hollow nanostructured Ni5P2/FeP4 nanoboxes (NiFeP NBs) are designed and synthesized as pre-catalysts. During the OER, the NiFeP NBs deeply reconstruct into low-crystalline and ultrathin NiOOH/FeOOH nanosheet assembled nanoboxes (NiOOH/FeOOH NBs). In situ Raman spectroscopy and ex situ characterization studies provide evidence that the hollow nanostructure facilitates the deep reconstruction of NiFeP NBs. Benefiting from the hierarchical hollow structure, the abundant interface between NiOOH and FeOOH, and plentiful defects, the reconstructed NiOOH/FeOOH NBs exhibit superior OER activity and excellent stability. Density functional theory (DFT) calculations reveal that the Fe–Ni dual sites in the NiOOH/FeOOH interface may be the possible active sites.

A new strategy incorporating three sequential treatments—selective molecular pre-masking, surface modification, and unmasking—is proposed for pore-size-dependent control of the surface properties of porous carbon materials. The method was experimentally validated using wide-pore-selective hydrophilization. n-Nonane was physically adsorbed for pre-masking, followed by room-temperature ozonation for surface modification. This process was used to introduce surface functional groups into wide pores, while leaving narrow pores intact. This study facilitates the development of new porous carbon materials with different surface properties that depend on pore size. This flexible strategy can be employed in conjunction with various molecular masking agents and surface-modification methods.

Simultaneous attainments of high conductivity and superior catalysis are major challenges for amorphous electrocatalysts in carbon dioxide electroreduction at high overpotential. In this study, one protocol is first demonstrated to drive the shell amorphization of nanoporous Ag-Bi (a-NPSB) catalyst with the spatially interconnected ligament during the initial stage of CO2ER. This newborn a-NPSB bestows the outstanding catalysis, evidenced by a Faradaic efficiency of 88.4% for formate production at -1.15 V vs RHE, specific current density of 21.2 mA cm-2, and mass specific current density of 321 mA mg-1. The unique catalysis is considered as the collective contribution of the conductive ligament internally and amorphous Bi2O3 shell with about 3.2 nm thickness externally. Simultaneous obtaining of the conductivity of inner metals and catalytic activity of the amorphous shell will pave a new avenue for designing a robust electrode during electrochemical reaction.

This work explores mechanical properties, structural evolution, and mechanism of creep-life enhancement for widely used P9 heat-resistant steel. The 17-year-on-site used P9 alloy exhibit a higher tensile strength and a smaller elongation than the new P9 alloy from room temperature to 700 °C. The P9 alloy also displays a typical ductile feature with a significantly necking profile. The P9 alloy shows phase transformation sequences of α-Fe (bcc) → A c 1 ∼ 858 ° C α + γ -Fe (bcc + fcc) → A c 3 ∼ 894 ° C γ-Fe (fcc) upon heating and γ-Fe (fcc) → M s ∼ 352 ° C martensite (bct) → M f ∼ 300 ° C martensite (bct) upon cooling. The new P9-alloy tube mainly contains ∼73.5% ferrite phase (α-Fe) and ∼26.5% carbide M3C. However, the used P9-alloy tube shows four crystalline phases including ∼45.9% ferrite, ∼14.5% martensite, ∼37.5% cementite (M3C) and ∼2.7% carbide M23C6. The creep test indicates that the used P9-alloy tube has a longer creep-life (or better anti-creep ability) than the new tube. Activation energies of atomic diffusion for the new and used tubes are respectively 252.45 and 345.87 kJ/mol, indicating a decreased diffusion capability in the used tube. This work suggests that martensite laths, lath boundaries, and precipitates (such as carbides) play important roles to inhibit creep-deformation in the P9-alloy steel.

Electrochemical carbon dioxide reduction meditated by metallic catalysts suffers from restricted selectivity and competition from hydrogen evolution, which sensitively depends on ambiguous contributions of alloying and strain state in bimetallic catalysts. Herein, nanoporous Au-Sn (NPAS) containing trace tin solute in Au lattices is delicately designed to convince real strain effect, while eliminating other undesirable factors, such as alloying, crystal facets and surface composition. Compared with nanoporous gold (NPG), the NPAS with a solute strain of ∼2.2 % enables more efficient CO2-to−CO conversion, with an efficiency as high as 92 % at -0.85 V versus reversible hydrogen electrode (vs. RHE), and the high activity can retain for more than 8 h. The combination of HRTEM and surface valence band photoemission spectra reveals that the tensile strain on the surface of 3D nanoporous structure promotes the catalytic activity by shifting up the d-band center and strengthening the adsorption of key intermediate *COOH. A small amount of Sn solute in the nanoporous alloy can prevent ligament coarsening effectively and improve the electrochemical stability.

Novel main-chain liquid crystalline Diels-Alder dynamic networks (LCDANs) were prepared that exhibit unprecedented ease for actuator programming and reprocessing compared to existing liquid crystalline network (LCN) systems. Following cooling from 125 °C, LCDANs are deformed with aligned mesogens self-locked at room temperature by slowly formed Diels-Alder (DA) bonds, which allows for the formation of solid 3D actuators capable of reversible shape change, and strip walker and wheel-capable light-driven locomotion upon either thermally or optically induced order-disorder phase transition. Any actuator can readily be erased at 125 °C and reprogrammed into a new one under ambient conditions. Moreover, LCDANs can be processed directly from melt (for example, fiber drawing) and from solution (for example, casting tubular actuators), which cannot be achieved with LCNs using exchangeable covalent bonds. The combined attributes of LCDANs offer significant progress toward developing easily programmable/processable LCN actuators.

The development of appropriate catalysts with relatively low cost, good selectivity and excellent stability is one of the major issues in electrochemical reduction of CO2. In this work, an efficient electrocatalyst was fabricated via ultra-small Co3O4 nanoparticles encapsulated within the tip of carbon nanotubes, denoted as Co/CNTs. Benefiting from the synergistic effects of highly active Co3O4 nanoparticles and well-graphitized carbon nanotubes, Co/CNTs exhibited remarkable performance in CO2 electroreduction. In a conventional H-type cell, CO with a 90% faradaic efficiency and 20.6 mA cm−2 partial current density was obtained at only −0.7 VRHE cathode potential with 40 hour stability. Upon switching to a gas-diffusion device, the CO partial current density could reach as high as 232.6 mA cm−2 with >80% faradaic efficiency, which might be even comparable to that of state-of-the-art CO2 electrocatalysts. Our work could also provide a new strategy for developing non-noble metal catalysts for CO2 electroreduction.

Extrusion temperature can significantly influence grain size, the shape of second phase particles and the dislocation distribution of Mg alloys. In this study, the effects of extrusion temperatures ranging from 250 to 400 °C on the microstructure, mechanical properties and corrosion resistance of a Mg-Al-Ca alloy with 1.61 wt.% Al and 1.76 wt.% Ca (Mg-1.61Al-1.76Ca) were investigated. The results showed that the size of grains and phases increased with an increase in extrusion temperature; the yield strength and ultimate tensile strength values decreased with an increase in temperature, while the fracture elongation increased initially (up to 300 °C) and decreased thereafter with an increase in temperature. Under test, the extruded alloy exhibited some evidence of corrosion at 250 °C, while extrusion at 300 °C demonstrated better corrosion resistance. Thus, the 300 °C extruded alloy possessed the optimum comprehensive performance because of the relatively small grains, fine second phase particles and fewer dislocations.

Carbon dioxide electroreduction provides a useful source of carbon monoxide, but comparatively few catalysts could be sustained at current densities of industry level. Herein, we construct a high-yield, flexible and self-supported single-atom nickel-decorated porous carbon membrane catalyst. This membrane possesses interconnected nanofibers and hierarchical pores, affording abundant effective nickel single atoms that participate in carbon dioxide reduction. Moreover, the excellent mechanical strength and well-distributed nickel atoms of this membrane combines gas-diffusion and catalyst layers into one architecture. This integrated membrane could be directly used as a gas diffusion electrode to establish an extremely stable three-phase interface for high-performance carbon dioxide electroreduction, producing carbon monoxide with a 308.4 mA cm−2 partial current density and 88% Faradaic efficiency for up to 120 h. We hope this work will provide guidance for the design and application of carbon dioxide electro-catalysts at the potential industrial scale., Here the authors deploy Ni single atom-decorated carbon membranes as integrated gas diffusion electrodes to construct an extremely stable three-phase interface for CO2 electroreduction, producing CO with a partial current density of 308.4 mA cm–2 and a Faradaic efficiency of 88% for up to 120 h.

Utilizing the self-assembly strategy between the paddle-wheel Cu2(COO)4 cluster and a terephthalic acid ligand modified by a triazolyl group, namely H2tztp = 2-(1H-1,2,4-triazol-1-yl)terephthalic acid, a porous MOF, [Cu0.5(tztp)0.5]·0.5DMA (1), has been successfully designed and built. 1 is a three-dimensional self-interpenerated framework with a (3,6)-connected rtl topology, and contains hydrophilic and hydrophobic channels decorated with rich uncoordinated triazolyl N atoms and benzene rings from tztp ligands, respectively. The unique porous environment leads not only to high gas adsorption amounts of CO2, C2H6, C2H4 and C2H2 but also to a good separation ability of C2 hydrocarbons over CH4, CO2 over CH4, and C2H2 over CO2 in the MOF. The specific adsorption sites of CO2 and C2 hydrocarbons were explored by a molecular simulation. The breakthrough experiments demonstrated excellent dynamic separations for CO2 and CH4, C2 hydrocarbons and CH4 as well as C2H2 over CO2. The MOF also revealed excellent adsorption and separation ability for CH3OH over other bulkier alcohol molecules.

Herein, a new porous Zn(II)-based metal-organic framework (MOF 1) has been prepared, the structure of which featured a twofold entangled motif based on two typical secondary building units (SBUs). The gas sorption studies indicated that MOF 1 may be explored as a useful platform to encapsulate metallic nanoparticles. Then the Au@1 composite has been prepared via a facile incorporation method without extra reducing agents. The Au@1 composite has been fully characterized by HRTEM, SEM-EDX, PXRD, gas sorption, XPS, ICP, etc. Catalytic experiments showed that the Au@1 composite had a perfect catalytic performance in CO2 fixation for epoxides with different substituents under mild conditions.

Previous evidence has shown that the increased expression of aurora kinase is closely related to melanoma progression and is an important therapeutic target in melanoma. Danusertib is an inhibitor of aurora kinase, and recent studies have shown that danusertib treatment induces autophagy in several types of cancer. Interestingly, autophagy plays a dual function in cancer as a pro-survival and anti-survival factor. In this study, we investigated the role of danusertib on the induction of autophagy in melanoma and determined the impact of autophagy induction on its anticancer activity against melanoma. Our results showed that danusertib can significantly inhibit melanoma growth by inducing cell cycle arrest and apoptosis. In addition, we demonstrated that danusertib treatment significantly inhibits the oncogenic Akt/mTOR signaling pathway and induces autophagy in melanoma cells. Furthermore, we identified that the inhibition of autophagy can enhance the inhibitory effects of danusertib on melanoma growth. Thus, the induction of autophagy by danusertib appears to be a survival mechanism in melanoma cells that may counteract its anticancer effects. These findings suggest a novel strategy to enhance the anticancer efficacy of danusertib in melanoma by blocking autophagy.

V-Cr-Al-O nanospheres were successfully synthesized using V2O5, Al(OH)3, CrO3, and H2C2O42O as the starting materials by a facile one-pot hydrothermal approach. Several techniques containing X-ray powder diffraction, hydrogen temperature programmed reduction, scanning electron microscopy were used to characterize the composition, morphology and redox property of V-Cr-Al-O nanospheres. The catalytic behavior of prepared nanospheres on the thermal decomposition of AP was investigated by the thermogravimetric analysis and differential thermal analysis (TG/DTA). The experimental results show that the thermal decomposition temperature of AP in the presence of V-Cr-Al-O nanospheres is to 395 °C (decreased by 35 °C), which proves better catalyst for the thermal decomposition of AP.

All-inorganic CsPbX3 (X = Cl, Br, and I) nanocrystals (NCs) are emerging as attractive semiconductor materials because of their outstanding optical properties. The low resistance of CsPbX3 NCs to light, heat, oxygen, and water has been recognized as a major obstacle to their practical applications. Here, we demonstrate that the stability of CsPbX3 NC films can be dramatically enhanced by Ar plasma treatment. It is revealed that plasma irradiation can induce ligand polymerization in the NC films if the ligands contain unsaturated carbon bonds. The ligand polymerization leads to encapsulation of the NCs in the ligand polymers. Because of the precise localization of the in situ ligand polymerization under plasma irradiation and the high NC content in the films without extra additives, the polymerized area can be precisely defined down to several micrometers. This enables easy fabrication of high-resolution NC pixels for next generation displays.

A series of new alkaline earth-metal organic frameworks (AE-MOFs), i.e. {[Mg2(μ6-L)(μ2-OH2)(H2O)4]·DMF}n (1), [Ca2(μ10-L)(EtOH)]n (2), [Sr(μ6-H2L)(MeOH)]n (3) and {[Ba1.5(μ5-H2L)(μ4-H3L)(H2O)3]·2(H2O)}n(4) were synthesized under solvothermal reaction by employing a symmetrical V-shaped multicarboxylic acid ligand H4L (H4L = 5,5′-oxydiisophthalic acid), resulting in versatile coordination modes as well as various topologies. 1 forms a uninodal 4-connected (66)-dia 3D topology based on dinuclear Mg2(COO)2(μ2-OH2) clusters. 2 displays an unprecedented 3-nodal (5,5,10)-connected 3D net with (424·621)(48·62)2 topology based on 1D [Ca(COO)]n chains and dinuclear Ca2(COO)2 clusters. 3 indicates a uninodal 6-connected 3D net with (410·65)-sma topology based on 1D [Sr(COO)]n chains. 4 features a new 4-nodal (4,5,6,6)-connected net with (43·63)2(46·64)2(46·68·8)(46·69)2 topology based on two types of 1D chains. 1-4 show solid-state fluorescent properties at ambient temperature. Especially, 1 and 2 have multiresponsive recognition of Fe3+ and Pb2+ ions, Fe3+ and Cu2+ ions, respectively, while 3 and 4 show single selective detection for Fe3+ ion, signifying that they could be potential fluorescent sensors for specific heavy metal ions in water system. The sensing mechanism has also been discussed in detail.

Summary The buccal mucosa (BM) is a critical first line of defense in terrestrial animals. To gain further insights into the evolutionary origins and primordial roles of BM in teleosts here we show that rainbow trout, a teleost fish, contains a diffuse mucosal associated lymphoid tissue (MALT) within its buccal cavity. Upon parasite infection, a fish immunoglobulin specialized in mucosal immunity (sIgT) was induced to a high degree, and parasite-specific sIgT responses were mainly detected in the buccal mucus. Moreover, we show that the trout buccal microbiota is prevalently coated with sIgT. Overall our findings revealed that the MALT is present in the BM of a non-tetrapod species. As fish IgT and mucus-producing cells are evolutionarily unrelated to mammalian IgA and salivary glands, respectively, our findings indicate that mucosal immune responses in the BM of teleost fish and tetrapods evolved through a process of convergent evolution., Graphical Abstract, Highlights • A mucosal associated lymphoid tissue is identified in teleost buccal cavity • Local immune responses can be induced in teleost buccal mucosa • Teleost IgT plays important roles in defending against buccal pathogen • Microbiota in teleost buccal mucosa is prevalently coated with secreted IgT, Biological Sciences; Immunology; Omics; Transcriptomics

A new porous metal-organic framework, namely [Co3(L)(OH)2(H2O)4]·NMP·3H2O (1), has been yielded by using Co(II) and rigid V-shaped 2,6-di(2′,5′-dicarboxylphenyl)pyridine (H4L). The structure analysis revealed that MOF 1 is a three-dimensional (3D) porous framework with 1D [Co3(OH)2]n ferromagnetic chains. The gas sorption measurements and the IAST analysis indicated MOF 1 has a relatively high selectivity for C2H6 and CO2 over CH4. The magnetic properties indicated that MOF 1 has the ferrimagnetic and slow magnetic relaxation behavior, giving an interesting single-chain magnet behavior with an effective energy barrier of 15.82 K.

Liquid-liquid transition (LLT) refers to the phase transition among thermodynamically distinct liquid states with identical composition in analogy to the polymorphic transition in solid. The growing awareness of its significance to understanding the nature of liquid also provokes curiosity about its potential impact on crystallization. Here, we report a first-order liquid-liquid transition above liquidus temperature in the melt of sodium acetate trihydrate using nuclear magnetic resonance, differential scanning calorimetry, and high-precision density measurements, which show negligible change in density associated with the observed LLT. Further, the kinetics and products of crystallization are significantly influenced by LLT, providing a new way for the controlling crystallization pathway and realizing crystal polymorph selection.

To synthesize novel polynuclear lanthanide single-molecule magnets, a tetranuclear dysprosium compound, namely [Dy4(L)4(OH)2(DMF)2(TMAA)2] •2 (CH3CN) (H2L = 2-(2-Hydroxy-3-methoxybenzylideneamino)phenol, HTMAA = trimethylacetic acid, DMF = dimethylformamide, and CH3CN = acetonitrile), was synthesized, structurally and magnetically characterized. The key structural feature of this compound is that four Dy(III) ions are nearly coplanar in a regular parallelogram, forming a distorted defective dicubane {Dy4O8} core. Furthermore, this compound shows Single Molecule Magnets (SMMs) behaviour with a high energy barrier of 56 K among tetranuclear Dy(III) SMMs.

Through a less-investigated in-situ hot-pressing synthesis method, the phosphotungstic acid H3PW12O40 (denoted as PW12) was rapidly incorporated into a metal-organic framework MFM-300(In) in a short time, affording novel PW12@MFM-300(In) composites. This solvent-free preparation process is not only environment-friendly but also energy/time-saving. The inclusion of PW12 in MFM-300(In) was demonstrated by different physical and chemical characterizations. It was interesting to find that PW12@MFM-300(In) as new heterocatalysts display synergistic activity for the visible-light-driven catalytic degradation of pharmaceutically active compound sulfamethazine (SMT). 4-PW12@MFM-300(In) with excellent robustness possesses the high removal efficiency of about 98% toward SMT within 2 h at room temperature, and can also be recycled multiple times for this catalytic process.

Using submicron Ba0.8Sr0.2Zr0.1Ti0.9O3 (BSZT) particles as a starting material, MgO as a material with high dielectric breakdown strength (BDS), and ZnO-B2O3-SiO2 (ZBSO) as a sintering agent, we rationally designed BSZT@MgO@ZBSO particles. The particles had a diameter of about 270 nm, high uniformity and high dispersity and were fabricated using a double-coating approach to simultaneously improve BDS and densification of the ceramics. The MgO and ZBSO layers in the BSZT@MgO@ZBSO particles averaged about 7 and 14 nm, respectively, in thickness. We obtained dense, fine-grained relaxor-like ferroelectric BSZT@MgO@ZBSO ceramics (grain size ≤ 300 nm) by sintering at 1140 °C for 2 h. As the ZBSO amount increased from 0.0 to 4.0 wt%, the discharged energy density increased to a maximum of 0.71 J/cm3 under a maximum polarization field of 24.1 kV/mm. As the ZBSO amount increased from 6.0 to 8.0 wt%, the discharged energy density decreased.

Electrochemical carbon dioxide (CO2) reduction into valuable chemicals is usually implemented at high overpotential, and most bimetallic catalysts suffer from the dramatic evolution of surface composition especially in case of long-term operation. In this work, as a proof-of-concept experiment, one effective protocol is first identified to drive the positive evolution of surface contents on nanoporous Cu-In by electrochemical training in KHCO3 electrolyte. Interestingly, superior performances including high selectivity for CO production and robust reliability are realized. Thus, Faradaic efficiency can approach the maximum of 91% at −0.95 V (vs. RHE), and an excellent durability can be simultaneously testified by no detectable performance decay for 7 h in operation. More importantly, current investigation paves a new road for designing bimetallic electrocatalysts with high selectivity and long-term durability.

In this work, the carbon-based microsphere with hollow-nanoflower structure was designed and applied to the targeted drug delivery system (TDDS) in order to improve drug loading and microwave control efficiency. We utilize the “silicon-assisted” method to tailor the hollow mesoporous carbon nanoflower (HMCNF) microspheres as base material, then small Fe3O4 particles (5–12 nm) were precipitated on the HMCNF by thermal decomposition and modified with SiO2 to obtain Fe3O4/HMCNF-SiO2 composites. The tailor-made Fe3O4/HMCNF-SiO2 has unique hollow “flower-dewdrops” structure, large BET surface area (292.21 m2/g) and uniform pore size (5.61 nm) to achieve large storage of drugs. Meanwhile, the Fe3O4/HMCNF-SiO2 has the appropriate magnetic properties (Ms = 8.91 emu/g) and good microwave heat transfer performance, which can achieve the drug carrier targeting and microwave-triggered release. Furthermore, the Fe3O4/HMCNF-SiO2 has a higher drug loading rate of 70.20% (DOX loading of 175.50 mg/g) and an expected release behavior. It maintains a very low drug release rate only 1.5% at pH = 7.4 and then increased to 25.2% after microwave stimulation at pH = 5.0. Therefore the Fe3O4/HMCNF-SiO2 composite nanocarrier is expected to widely use in microwave-triggered drug delivery system.

In order to explore the metal ions-controlled syntheses of coordination polymers (CPs), the temperature and solvent ratio were fixed in the reaction processes. By selecting a series of s- and d-block metal ions, five new CPs, [ZnL0.5(H2O)2]n (1), [CoL0.5(H2O)2]n (2), [Mn(H2L)(H2O)2]n (3), [Ca(H2L)(H2O)2]n (4) and [Ba(H2L)(H2O)2]n (5), have been synthesized by employing a less-investigated oxalamide N,N′-bis(4-phthalic acid) (H4L) ligand. H4L shows very versatile coordination modes and leads to various frameworks, including isomorphous 2D grid-like layer based on M2O2 cores for 1 and 2, isomorphous 4-connected 3D PtS frameworks based on 1D [M(CO2)2]n chains for 3 and 4, and a 2D wave-like layer based on [BaO3]n chains for 5.2 and 3 reveal the antiferromagnetic and ferromagnetic properties, respectively, while 1, 4 and 5 possesses strong solid state luminescence.

Four new water-stable luminescent metal-organic frameworks (MOFs), namely {[Zn4(L)2(H2O)4(OH)2]·3NMP}n (1), {[Zn3(L)2(H2O)2]·Diox}n (2), {[Cd3(L)2 (H2O)5]·NMP·3H2O}n (3), and {[Pb3(L)2(NMP)2(H2O)]·H2O}n (4), (H3L = 5-(1-(carboxymethyl)pyrazol-3-yl)isophthalic acid; NMP = N-methyl-2-Pyrrolidoneand; Diox = 1,4-Dioxane) have been solvothermally synthesized with different solvents. The single crystal structures of 1–4 reveal that complexes 1 and 2 form the 2D (3,6)-connected kgd nets based on the tetranuclear [Zn4(μ1-COO)2(μ2-COO)4] clusters and trinuclear [Zn3(μ1-COO)2(μ2-COO)4] clusters, respectively. Complex 3 displays a 2D (3,6)-connected kgd net based on the trinuclear [Cd3(μ1-COO)4(μ2-COO)2] clusters. Complex 4 presents a 2D layer with a rod-shaped SBUs. The solid-state luminescence properties and water stability of these complexes were investigated carefully, showing that 1 displays high selectivity for Fe3+, CrO42−, and Cr2O72− via luminescence quenching effects with low detection limits. The probable quenching mechanisms have been studied in detail.

As backup energy storage devices, flexible microsupercapacitors (MSC) are expected to play an important role in future self-powered microelectronics. Graphene-based MSCs have attracted substantial attention due to their power performance, excellent mechanical flexibility, and superb cycling stability. The enhancement of the electrochemical performance of graphene-based MSCs is crucial for their practical application but remains a challenge. Herein, we report an electrochemically exfoliated O, P-functionalized holey graphene (FHG) with a hierarchical porous structure for high-performance flexible MSC electrodes. The areal capacitance increases linearly with the thickness of the electrode owing to the high ion-accessible surface area as well as efficient electron and ion transport pathways. The as-fabricated FHG-MSC delivers an areal capacitance of 6.41 mF cm−2, a volumetric capacitance of 30.51 F cm−3, and a high energy density of 4.24 mW h cm−3. Additionally, the MSC possesses exceptional mechanical flexibility with ∼99.7% capacitance retention over 500 bending cycles. Such outstanding results make it possible to use FHG in future high-performance self-powered microelectronics and provide a novel strategy for preparing few-layer functionalized holey graphene (FHG).

The control problem for quadrotor UAVs is difficult and challenging due to the complex nonlinear dynamics and ever-changing disturbances. In this paper, a supplementary controller based on reinforcement learning (RL) is proposed to improve the control performance of quadrotor UAVs. The proposed RL method is constructed by an actor-critic structure and some improved technologies, e.g., Q-learning, temporal difference, and experience replay. With the proposed method, the speed and stability of training can be improved greatly. On one hand, the supplementary controller can work together with the traditional controller online, which can guarantee the stability of the system. On the other hand, the model uncertainties and external disturbances could be restrained through online RL training. The Lyapunov theory is used to prove the convergence of the RL controller's weights theoretically. Finally, three simulations are provided to illustrate the effectiveness of the proposed controller.

Herein, two new water-stable magnetic frameworks, [Cu1.5(L)(H2O)]·2H2O (1) and [Co4(L)2(CH3CN)(OH)2(H2O)4]·3H2O (2) (H3L = 5-((4-carboxypyridin-2-yl)oxy) isophthalic acid), were synthesized by a solvothermal method in similar reaction systems and characterized by infrared spectroscopy, powder X-ray diffraction and thermogravimetric measurements. Due to their different metal ions, 1 shows a trinodal (4,4,4)-connected three-dimensional (3D) framework that possesses 1D channels based on [Cu2(COO)4] paddle-wheel secondary building units (SBUs), whereas 2 is a 2D layered network based on tetranuclear [Co4(COO)6(μ3-OH)2] SBUs and reveals a (3,6)-connected kgd topological structure. The gas adsorption explorations demonstrated that 1 exhibited commendable selectivity for CO2 over CH4. Moreover, both 1 and 2 showed different degrees of antiferromagnetic exchange action.

A novel two-dimensional Cd-based metal–organic framework, {[Cd(Hcpnc)(DMF)]·DMF·2H2O}n (Cd-MOF) has been synthesized successfully under solvothermal conditions by utilizing a multifunctional N,O-building block ligand, 2-(2,5-dicarboxylphenyl)nicotinic acid (H3cpnc), which is a new and virtually unexplored multifunctional pyridine-tricarboxylic building block. The product was isolated as a stable crystalline solid and was fully characterized by IR spectroscopy, elemental analyses, thermogravimetry and differential scanning calorimetry, powder X-ray diffraction, single-crystal X-ray diffraction analyses, and X-ray photoelectron spectroscopy. The solid-state luminescence properties of the Cd-MOF were studied at ambient temperature. The compound shows high selectivity and sensitivity for Cu2+ ions and nitrobenzene by the luminescence quenching behavior with excellent repeatability. Additionally, the Cd-MOF exhibits an excellent specific capacitance of 321 F g−1 at 0.5 A g−1 and it still retains 95.2% of the original capacitance after 1000 cycles. Therefore, the Cd-MOF as a kind of bifunctional material will have broad application prospects in luminescence detection and supercapacitors.

Due to their high theoretical specific capacity, CoSe2-based anode materials have attracted enormous attention for sodium storage. However, the poor cycling stability and rate capability still hinder their application. Herein, starting from Co3[Co(CN)6]2 Prussian blue analogue microcubes, a facile template-engaged strategy is developed to design and synthesize nanostructured dual-carbon-confined CoSe2 (denoted as DCC-CoSe2) microcubes. In this unique nanostructure, N-doped carbon-coated CoSe2 nanoparticles are confined in N-doped carbon microboxes. Benefiting from the desired structural features, the as-synthesized DCC-CoSe2 microcubes exhibit enhanced sodium storage properties in terms of high specific capacity (480 mA h g−1), excellent cycling stability (94.5% capacity retention over 2000 cycles), and superior rate capability (281 mA h g−1 at 20 A g−1). The assembled full cell with DCC-CoSe2 microcubes as the anode material and Na3V2(PO4)3 as the cathode material can deliver a high initial capacity of 427 mA h g−1. This work provides a new strategy for the rational design and synthesis of high performance metal selenide-based anode materials for sodium storage.

Solution-processed bulk heterojunction (BHJ) solar cells based on ternary blends have previously achieved high power conversion efficiencies (PCEs). In this study, we obtained a combination of good cell performance and high thermal stability for an inverted ternary organic solar cell based on a single polymer donor (PTB7-Th) and two acceptors: one a polymer (N2200) and the other a fullerene component (PC71BM). The ternary blended film based on PTB7-Th:N2200:PC71BM at a composition of 2:0.5:2.5 (w/w/w) featured suitable cascade energy levels, a broad comprehensive absorption region, and smooth interfaces; its corresponding device exhibited a best PCE of 6.2%, an open-circuit voltage of 0.82 V, and a short-circuit current density of 14.4 mA cm−2. After introducing 1% of 1,8-diiodoctane (DIO), the highest PCE reached 7.7%. Furthermore, this ternary cell exhibited good long-term thermal stability after annealing at 100 °C for 1000 h.

A series of twisted N,N-linked benzo[ghi]-perylenetriimide dimers (t-BPTI) with various lengths of the α-branched alkyl side chain at the six-membered imide ring position was designed, synthesized, and characterized. These compounds showed the low-lying LUMO energy level of -3.78 eV, which was similar to that of PC61 BM (-3.71 eV), but with intensive optical absorption in the range 350-500 nm. The twisted molecular geometry with two nearly perpendicular BPTI planes achieved a favorable nanoscale phase separation by relieving the self-aggregation of rigid BPTI units in blend films. The acceptor t-BPTI-3 unit with the longest alkyl side chains has been demonstrated to be an efficient electron acceptor in solution-processed bulk heterojunction organic photovoltaics (OPV), giving a power conversion efficiency of 3.68 % when using conjugated polymer PTB7-Th as the donor and without additional treatments.

In this study, two size-controllable silver nanoparticles, decahedral and icosahedron Ag NPs, were embedded into PEDOT:PSS as hybrid hole transporting layer (HTLs) for organic photovoltaic applications. The Ag-decahedral based nanoparticle exhibited rather red-shifted and larger domain size than Ag-icosahedron one. Due to the plasmonic and light harvesting effects of Ag NPs, the power conversion efficiency (PCE) was increased from 5.8% to 6.5 (decahedral-based) and 6.3% (icosahedron-based) in Poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7):[6,6]-Phenyl C71-butyric acid methyl ester (PC71BM) based-OPV upon embedding the Ag NPs. External quantum efficiency (EQE) enhancement was also observed due to the plasmonic scattering effect. The atomic force microscope (AFM) images showed the roughed results of the PEDOT:PSS/Ag NPs hybrid HTL films, i.e. better hole collection efficiency. Furthermore, the active layer did not show any aggregation and morphology change after adopting hybrid HTL films into the devices.

A new aluminium-plated structure with transition circular arcs used for railway vehicles is presented. Two impact experiments were performed using a test trolley to examine the plastic response and fracturing of the aluminium-plated structure. The results show that the deformation mode of the aluminium-plated structure switches from global plastic bending deformation to local fracturing at the transition circular arc region, which is consistent with the design. Numerical results are presented in terms of deformation modes, force responses and levels of absorbed energy, demonstrating good agreement with the experimental results. From the results of the numerical simulation, fracturing processes and variations in element stress triaxiality are presented. It is found that the stress state of elements affecting the initiation of cracking is of a tension state, while the stress state of elements affecting the end of cracking is of a shear state. A validated finite element analysis of an aluminium-plated structure with right-angled, circular arcs and chamfering transition sections is presented. Plastic and fracture energy levels of the aluminium-plated structure with three transition sections are measured as 2.56, 27.62, and 30.13 kJ and 0.98, 2.41, and 2.16 kJ, respectively, as the second fracturing point. Finally, the finite element analysis illustrates the impact energy effects involving different combinations of trolley mass and velocity, and experimental boundary conditions for varying bolt yield stress and pre-stress levels are defined in the finite element model to investigate the effects of bolted joints on the dynamic responses of an aluminium-plated structure with transition circular arcs.

International audience; Alloy melts can solidify into metallic glasses if cooled fast enough to avoid crystallization. Glass-forming ability (GFA), a measure of the ease of vitrification, is vital for the fundamental understanding of glass formation, and is also crucial for the application of metallic glasses. Previous studies of GFA mainly focused on the undercooled liquid phase, while the influence of the evolution of the stable melts on GFA is rarely addressed. Here we show that the Pd42.5Ni42.5P15 glass-forming liquid, in which a first-order liquid-liquid transition (LLT) takes place at TLL = 1063 K high above its liquidus temperature, shows significantly different GFA when quenched from the temperature above or below TLL. Moreover, the pathway and kinetics of crystallization of the melt are strongly related to the kinetics of the LLT. Our work provides new insights into the vitrification process and the kinetics of crystallization, and contributes to designing more stable metallic glasses.

Segmentation of layers in retinal images obtained by optical coherence tomography (OCT) has become an important clinical tool to diagnose ophthalmic diseases. However, due to the susceptibility to speckle noise and shadow of blood vessels etc., the layer segmentation technology based on a single image still fail to reach a satisfactory level. We propose a combination method of structure interpolation and lateral mean filtering (SI-LMF) to improve the signal-to-noise ratio based on one retinal image. Before performing one-dimensional lateral mean filtering to remove noise, structure interpolation was operated to eliminate thickness fluctuations. Then, we used boundary growth method to identify boundaries. Compared with existing segmentations, the method proposed in this paper requires less data and avoids the influence of microsaccade. The automatic segmentation method was verified on the spectral domain OCT volume images obtained from four normal objects, which successfully identified the boundaries of 10 physiological layers, consistent with the results based on the manual determination.

Ultraviolet radiation (UVR) and noise are the ubiquitous environmental hazards with considerable detrimental effects on the physiological and psychological health of humans. Exploiting efficient protective materials that can be extensively used in daily life for simultaneous anti-UVR and noise mitigation will be of crucial importance, but it is still a significant challenge in materials design. Herein, we developed a series of protective textiles for efficient anti-UVR and noise reduction via MOFs nanocrystal-modified cotton textiles. The formation of MOFs@cotton textiles was confirmed by using electron microscopy, X-ray diffraction, infrared spectroscopy, and X-ray photoelectron spectroscopy. The fabricated MOFs@cotton textiles exhibited substantial improvement in the UVR blocking and acoustic absorption properties compared to blank cotton textiles. Therefore, this work provides a good strategy for designing and preparing multifunctional protective textiles.

Liquid crystalline network (LCN) actuator normally deforms upon thermally or optically induced order-disorder phase transition, switching once between two shapes (shape 1 in LC phase and shape 2 in isotropic state) for each stimulation on/off cycle. Herein, we report an LCN actuator that deforms from shape 1 to shape 2 and then reverses the deformation direction to form shape 3 on heating or under light only, thus completing the shape switch twice for one stimulation on/off cycle. The deformation reversal capability is obtained with a monolithic LCN actuator whose two sides are made to start deforming at different temperatures and exerting different reversible strains, by means of asymmetrical crosslinking and/or asymmetrical stretching. This desynchronized actuation strategy offers possibilities in developing light-fueled LCN soft robots. In particular, the multi-stage bidirectional shape change enables multimodal, light-driven locomotion from the same LCN actuator by simply varying the light on/off times., Liquid crystalline network (LCN) actuators switch reversibly between two states. Here, the authors report an asymmetrically processed LCN actuator which allows desynchronized actuation between three states using light and thermal stimuli.

Although silicone implants are the most popular choice around the world for breast augmentation, reconstruction, and revision, due to the poor antibacterial properties and limited biocompatibility of silicone rubber (SR), one of the major complications, capsule contracture, is a lingering problem. To overcome the two main shortcomings, a dual ion implantation technique was applied to modify the surface of SR with the basic skeleton element of organic matter, carbon (C) and the broad-spectrum bactericide, silver (Ag). We present surface characterization, toxicological effects, and evaluation of the mechanical, antibacterial and biocompatible properties of C and Ag co-implanted SR (C/Ag-SRs). After ion implantation, surface roughness and tensile strength of these new materials increased. Biotoxicity was fully assessed by in vitro experiments on human fibroblasts and in vivo experiments on rats, showing that the low-Ag groups met safety standards. Both the anti-bacterial adhesion and bactericidal abilities of C/Ag-SRs were superior to those of SR, which had few antibacterial activities, especially against Staphylococcus epidermidis. With respect to biocompatibility, the adhesion of fibroblasts was promoted, while their proliferation was moderately inhibited on ion-implanted surfaces. After subcutaneous implantation in rats for 7, 30, 90 and 180 d, the capsular thickness around C/Ag-SRs was significantly lower than that around the SR. Additionally, there was no difference in the inflammatory reaction after 7 d of retention in vivo between C/Ag-SRs and SR. The results demonstrate that C/Ag-SRs are desirable shell materials for breast implants.

To improve the computed tomography (CT) imaging ability and the toxicity of gold nanoparticles (AuNPs), hydrophilic dopamine (DPA)-coated gold nanoparticle (AuNP) (MSA AuNPs@DPA) aggregates (42 ± 2.65 nm) were obtained by assembling MSA AuNPs@DPA (5–6 nm) with the use of polyethyleneimine (PEI). They rapidly degraded into MSA AuNPs@DPA with PEI in blood. The acute toxicity test showed that the maximum tolerated doses of MSA AuNPs@DPA and MSA AuNPs@DPA aggregates were larger than 4.8 and 4.6 g kg−1, respectively, which are much higher doses than those of the commonly used citric acid-stabilized AuNPs (CA AuNPs) (2.97 g kg−1). The metabolic test in vivo showed that the elimination rates of MSA AuNPs@DPA aggregates and MSA AuNPs@DPA were 0.848 and 0.955, respectively. Most of the aggregates were eliminated by the kidney after 5 days and excreted by urine, whereas CA AuNPs remained in vivo and concentrated in some organs. The t0.5 values of MSA AuNPs@DPA and MSA AuNPs@DPA aggregates were 24.28 and 43.68 h, respectively, meaning that MSA AuNPs@DPA aggregates had a much longer circulation time. Similarly, the CT absorption value of MSA AuNPs@DPA aggregates was much higher than that of the commonly used nonionic iodinated CT contrast agent iohexol and CA AuNPs at the same concentration. Thus, MSA AuNPs@DPA aggregates possess characteristics such as ease of fabrication, long circulation time, hypotoxicity, and excellent CT absorption value, which suggest their great potential applications in vivo.

By employing the ligand 2-(isonicotinamido)terephthalic acid (H2L) containing the amide functional groups, a Cd-MOF, {[Cd2L2(H2O)2]·4H2O}n (1) has been constructed by solvothermal synthesis. The dinuclear clusters [Cd2(COO)2] in 1 are linked by the pyridinyl and carboxylate groups of ligands to form a three-dimensional (3D) skeleton, containing 1D channels with the free amide groups. The activated framework shows good stability in water and high selectivity for CO2 over CH4. The open Cd2+ site as Lewis acidic center makes the MOF achieve efficiently catalytic conversion for CO2 cycloaddition with epoxides. Furthermore, 1 also exhibits good chemical stability in water, allowing the detection for ronidazole (RDZ) and dimetridazole (DTZ) with the low detection limit and rapid response.

To comparably analyze the influence of a porous environment on the gas adsorption in MOFs, based on an imidazole-decorated MOF, {[Zn(imtp)]·DMA·1.5H2O}n (1-im, H2imtp = 2-(imidazol-1-yl) terephthalic acid), an analogue MOF, {[Zn(tztp)]·DMA}n (1-tz, H2tztp = 2-(1H-1,2,4-triazol-1-yl) terephthalic acid) has been synthesized by replacing imidazole with triazole motifs. The two MOFs are isostructural frameworks containing 1D channels; however, they possess different porous wall environments. The open nitrogen-decorated channels in 1-tz lead to significantly enhanced C2H6 (76.5 cm3 g–1) and C2H4 (73.1 cm3 g–1) uptakes at 298 K and 1 atm, which are 5 times of the adsorption amounts of C2H6 and C2H4 in 1-im that is the absence of exposed N atoms in the channels. Furthermore, the activated 1-tz also reveals higher adsorption selectivities for C2H6 and C2H4 over CH4. The different sorption properties were further uncovered by theoretical simulations.

We have prepared an efficient ternary polymer solar cell incorporating a poly(indacenodithiophene)-based conjugated polymer (PIDTBT), [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), and 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)indanone)-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2´,3´-d´]-s-indaceno[1,2-b:5,6-b´]-dithiophene (ITIC). Grazing-incidence wide-angle X-ray scattering (GIWAXS), atomic force microscopy (AFM), and photoluminescence (PL) spectroscopy revealed that intermolecular interactions between the PC71BM and ITIC units disrupted the formation of large ITIC crystals. The ITIC and PC71BM components formed compatible domains that dispersed well within the PIDTBT matrix, providing optimized ternary blends for efficient carrier transport and led to greater photon-to-electron conversion efficiency. Compared with the pre-optimized PC71BM binary device, the ternary device displayed an improvement in short circuit current density (Jsc) from 12.0 ± 0.3 to 14.2 ± 0.5 mA cm–2, due primarily to complementary light harvesting in the visible and near-infrared regions; as a result, the device performance improved by 20%—from 5.5 ± 0.2 to 6.6 ± 0.1% under AM 1.5G (100 mW cm–2) irradiation. Furthermore, the ternary cell exhibited outstanding long-term stability, with its performance remaining high (at 6.8%) after storage for 410 days in a glove box (ISOS-D-1 (shelf lifetime)).

Hydrothermal reaction of flexible 4,4′-oxybis(benzoic acid) (H2oba), semi-rigid 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and Cu(OH)2 led to an interesting 2D → 3D polythreaded architecture of MOF [Cu2(bpt)2(oba)2(H2O)]n·4nH2O (1). Accomplished with the rising synthesis temperature, two chiral MOFs [Cu4(bpt)4(oba)4]n (L-2 and D-2), have been obtained from the congenetic nonchiral precursors upon spontaneous resolution, which represent a rarely example of temperature-induced threefold interpenetrating enantiomerically arm-shaped MOFs constructed from achiral symmetrical ligands.