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• A buckling-regulated origami material is proposed by synergy design of multiple origami features. • The properties of both developable and undevelopable origami are improved in proposed buckling-regulated materials. • A mechanical model for predicting the property of the buckling-regulated origami material is established. Origami is an emerging class of structural materials that can display remarkable physical and mechanical properties due to its unique deployability, while simple combination of deployable and undeployable features lead to more fantastic mechanical properties because of the extended design freedom. To further exploit the application potential of multiple origami features, a buckling-regulated origami material is proposed in this work by synergy design instead of simple combination of different origami features. In details, three buckling-regulated mechanisms are incorporated into the origami materials using synergy design, i.e., controlling global bulking via deployable folding, controlling local buckling through cell structure arrangement, and reproducing high energy-absorbing deformation mode using undeployable features. According to the synergic effect of multiple origami features, the buckling-regulated origami material improves both the resistance of deployable origami and instability of undeployable deformation. To validate this, the corresponding origami materials are manufactured by 3D printing technology, and experimentally tested. The manufactured origami materials show anticipated properties under quasi-static compression, i.e., high resistance and protracted steady plateau. Furthermore, due to the structural characteristics of origami and the tailorability of mechanical properties, it may inspire new innovations in designing other multi-functional metamaterials. [Display omitted] [ABSTRACT FROM AUTHOR]

Triply periodic minimal surface (TPMS) has attracted extensive attention in recent years due to its unique, symmetric, and non-self-intersecting features. In this study, the mechanical behaviors of 3D-printed polymeric TPMS sheets were experimentally investigated. The eighteen specimens of six different configurations (including Schwarz Primitive, Schoen Gyroid, Skeleton, Schoen I-WP, Schwarz Diamond, and P-W Hybrid) were fabricated by means of fused filament fabrication (FFF) technique in poly lactic acid (PLA) polymer. These structures were quasi-statically compressed via uniaxial INSTRON 1342 machine. Their mechanical behaviors were evaluated in terms of crashworthiness indicators, compression characteristic, deformation process, specific force, and normalized criteria. The results show that the 18 specimens experience the classical characteristics of cellular structure during collapse process. P-W Hybrid structure processes good energy absorption, and load bearing capacity compared with other structures. Schoen I-WP structure experiences good collapse pattern with layer-by-layer folding sequence. The investigated structures are ranked by in a comprehensive manner through a normalized criterion as follow: P-W Hybrid > Schwarz Diamond > Schoen I-WP > Skeleton > Schoen Gyroid > Schwarz Primitive. [ABSTRACT FROM AUTHOR]

Thermo-oxidative aging plays an important role in changing the properties of rubber materials; it significantly decreases the fatigue life of air spring bags and further causes safety hazards. However, due to the great uncertainty of rubber material properties, an effective interval prediction model has not been established considering the effect of aging on airbag rubber properties. To solve the problem, this study proposes an interval parameter correlation model that can more accurately describe rubber crack propagation characteristics by considering material uncertainty. Furthermore, an aging prediction model of the rubber crack propagation characteristic region is established based on the Arrhenius equation. The effectiveness and accuracy of the method are verified by comparing the test and prediction results under the temperature spectrum. The method can be used to determine the variations in the interval change of the fatigue crack propagation parameters during rubber aging and can guide fatigue reliability analyses of air spring bags. [ABSTRACT FROM AUTHOR]

Low-cost and processable polyimides with ultrahigh thermal/chemical stability is urgently demanded in microelectronic and aeronautics/astronautics industries. In this work, crystalline polyimides containing reactive cyano groups were synthesized from readily available monomers by facile one-step solution polycondensation method. The obtained polyimides are soluble at room temperature in the common solvents, and can be easily made into transparent polymer films. After curing, the resultant products become completely insoluble in any solvents, exhibiting excellent chemical stability. The glass transition temperature (T g) and 5% thermal decomposition temperature (T 5) for the cured polyimides are as high as 462 °C and 570 °C, respectively. The ultrahigh T g and T 5 together with good solubility are superior to most polyimides already reported in the literature. Moreover, the polyimide films are quite tough with the tensile strengths of 94–118 MPa, Young's moduli of 2.3–2.7 GPa and elongations at break of 5.3%–8.6%. The combination of facile synthesis method, solution-proccesability, excellent thermal/chemical resistance and mechanical property endows the polymers with promising applications in polymer films and composite materials. [Display omitted] • Crystalline cyano-containing polyimides are synthesized via a facile method. • The polyimides are self-crosslinkable and soluble at room temperature. • The cured products possess ultrahigh glass transition temperature up to 462 °C. • The 5% weight-loss temperature of the polyimides reaches 570 °C. • The water uptake measured in the boiling water for 24 h is as low as 1.39%. [ABSTRACT FROM AUTHOR]

In the Dempster–Shafer evidence theory framework, extremum analysis, which should be repeatedly executed for uncertainty quantification (UQ), produces a heavy computational burden, particularly for a high-dimensional uncertain system with multiple joint focal elements. Although the polynomial surrogate can be used to reduce computational expenses, the size of the solution space hampers the efficiency of extremum analysis. To address this, a solution-space-reduction-based evidence theory method (SSR-ETM) is proposed in this paper. The SSR-ETM invests minimal additional time for potentially high-efficiency returns in dealing with epistemic uncertainty. In the SSR-ETM, monotonicity analysis of the polynomial surrogate over the range of evidence variables is first performed. Thereafter, the solution space can be narrowed to a smaller size to accelerate extremum analysis if the surrogate model is at least monotonic in one dimension. Four simple functions and an air spring system with epistemic uncertainty demonstrated the efficacy of the SSR-ETM, indicating an apparent superiority over the conventional method. [ABSTRACT FROM AUTHOR]

The evaluation of objective functions and component reliability in the optimisation of structural-acoustic systems with random and interval variables is computationally expensive, especially when strong nonlinearity exhibits between the response and input variables. To reduce the computational cost and improve the computational efficiency, a novel anisotropy-based adaptive polynomial chaos (ABAPC) expansion method was developed in this study. In ABAPC, the anisotropy-based polynomial chaos expansion, namely the retained order of polynomial chaos expansion (PCE) differs from each variable, is used to construct the initial surrogate model instead of first-order polynomial chaos expansion in conventional methods. Then, an anisotropy-based adaptive basis growth strategy was developed to reduce the estimation of the coefficients of the polynomial chaos expansion method and increase its computational efficiency. Finally, to solve problems with probabilistic and interval parameters, an adaptive basis truncation strategy was introduced and implemented. Using the ABAPC method, the computational cost of reliability-based design optimisation for structural-acoustic systems can be efficiently reduced. The effectiveness of the proposed method were demonstrated by solving two numerical examples and optimisation problems of a structural-acoustic system. [ABSTRACT FROM AUTHOR]

Acoustic metamaterials with broadband sound-absorbing capacity open up applications in aerospace, automotive, marine, defense, etc. For such applications, sound-absorbing materials that can withstand complex loading conditions are essential. Hence, to address acoustic and mechanical requirements simultaneously, we propose plate-reinforced dual-functional micro-lattice metamaterials (PDMMs) that exhibit elastic isotropy, dual crushing stages with a specific energy absorption up to 25.82 kJ/kg, and ultra-broadband sound absorption from 0.97 kHz to 6.30 kHz. The remarkable elastic isotropy lies in the topology-induced structural stiffness homogenising effect. The transition from single to dual plateau anti-compression stages is controlled by tailoring the structural local strength. On-demand broadband sound absorption is achieved by modulating the parallel coupling and cascade resonance effects, and the physical mechanism is revealed by examining impedance matching and system damping states. Overall, the presented novel metamaterials exhibit exceptional application potentials by overcoming the trade-offs usually found in traditional mechanical and acoustic metamaterials. [ABSTRACT FROM AUTHOR]

The compressive behavior of the cellular concrete utilizing millimeter-size spherical saturated SAP with different porosities was experimentally investigated under quasi-static and high strain-rate loadings. Quasi-static tests at strain rate of 10 −5 /s were conducted using a servo-hydraulic material test system. Impacting tests at strain rates ranging from 70/s to 140/s were performed using Φ74 mm conic variable cross-sectional split Hopkinson pressure bar (SHPB) equipment. The strain rate effects on the failure pattern, compressive strength, elastic modulus and critical strain were studied. The results indicated that the compressive strength and elastic modulus increased with increasing strain rate and displayed clear strain-rate dependence. At high strain rates the compressive strength decreased with increasing the porosity, while dynamic increase factor of the compressive strength ( DIF-f c ) showed a reverse tendency. Furthermore, the elastic modulus and its dynamic increase factor ( DIF-E ) both decreased with increasing the porosity at given high strain rate. [ABSTRACT FROM AUTHOR]

• A rate-sensitive and pressure dependent failure criterion was proposed for hail ice. • The rate-sensitivity of tensile failure strength was also incorporated. • The model can predict the ice impact forces and failure patterns reasonably well. Hail is a common natural threat to humans, constructions, and any facilities exposed to it, while there appears to be limited models that are able to accurately capture the mechanical behavior of hail ice, especially its dynamic response to impact. To address this, a rate-sensitive pressure-dependent failure criterion was proposed using a linear combination of the rate-dependent von-Mises equivalent stress and the hydrostatic pressure. After determining the linear combination coefficient via comparison between a series of simulations and experiments, the proposed criterion was used to predict the peak force during impact, for ice balls of different diameters and impact speeds. Both the peak forces and failure patterns during impact predicted using the proposed criterion correlate with experimental results reasonably well, indicating that the proposed criterion is able to accurately capture the dynamic response of ice to impact. [ABSTRACT FROM AUTHOR]

Porphyrin- and cobalt (II)-metallated porphyrin-based porous polyaminals (PAN-TDP and Co@PAN-TDP) were synthesized via one-step polycondensation reaction utilizing octo-functional 5,10,15,20-tetrakis (4-(2,4-di-aminotriazinyl)phenyl)-porphyrin (TDP) and cobalt (II)-metallated porphyrin (Co@TDP) to polymerize with terephthalaldehyde, respectively. The achieved BET surface areas (1535–1589 m2 g−1) are the largest among the aminal-linked porous polymers already published in the literature. The synergistic role of nitrogen-rich polymer skeleton, ultramicroporous and microporous structure, and large specific surface area in Co@PAN-TDP gives rise to high adsorption capacity of CO 2 (17.9 wt%, 273 K/1 bar). Meanwhile, Co@PAN-TDP exhibits excellent heterogeneous catalysis performance for the cycloaddition reactions of CO 2 with various epoxides. Of particular interest is that the silicon- and sulfite-containing cycloaliphatic di-epoxides can be converted to cyclic di-carbonates with high conversion rates (88.7–90.5%) and TON values (825–842) despite the large steric hindrance. The generated novel silicon- and sulfite-containing cycloaliphatic di-functional carbonates are potential monomers for the preparation of isocyanate-free polyurethanes. [Display omitted] • Cobaltoporphyrin-Supported Porous polyaminal Co@PAN-TDP is synthesized. • BET surface area up to 1589 m2 g−1 is the highest among aminal-linked porous polymers. • Co@PAN-TDP gives rise to high adsorption capacity of CO 2 (17.9 wt%). • Co@PAN-TDP can efficiently convert cycloaliphatic di-epoxides to di-carbonates. • After five cycles, the catalytic performance of Co@PAN-TDP remain unchanged. [ABSTRACT FROM AUTHOR]

• The Jacobi-polynomial and the segmentation strategy are adopted to control the dynamic stiffness matrix size and sparsity of the FE method in the vibration problems. • Various types of geometric shapes of quadrilateral flats and curved plates are considered in the free and forced vibration studies. • A study of the influence of lamination angle on the vibration characteristics of the composite laminate of the curved plates is conducted. The finite element method is widely applicable to various kinds of models. Nonetheless, as the size and frequency domain of the solving model increase, it encounters challenges related to high memory consumption and slow solution speed. To enhance the computational efficiency while preserving its existing advantages, this study incorporates the Jacobi polynomial with a segmentation strategy into the finite element method for addressing the vibration analysis of composite laminate quadrilateral flat and curved plates. In this method, the dynamic stiffness matrix of a finite element is multiplied on both sides by a matrix composed of Jacobi polynomial basis functions, thereby transforming the expression form of the dynamic stiffness matrix from FE form to meshless form and reducing its size. Additionally, the segmentation strategy is introduced to divide the model into multiple blocks, enhancing convergence and calculation efficiency by altering the sparsity pattern of the dynamic stiffness matrix. Convergence research, validation studies, limitations studies, and parametric studies are conducted. The method demonstrates evident advantages in computational efficiency for random surface quadrilateral models requiring dense mesh description while maintaining a certain level of accuracy. [ABSTRACT FROM AUTHOR]

[Display omitted] • A synergic approach is proposed to effectively eliminate the absorption valley and enhance coupling strength. • The efficient broadband sound absorption of hierarchical-porous acoustic metamaterial is achieved. • The experimental results demonstrated an average absorption coefficient of 0.77 within the range of 400–1600 Hz. • An ultra-broadband spectrum exceeding 3.4 kHz was achieved by integrating the scaling effect and the energy-trapped mode. A novel design for hierarchical-porous acoustic metamaterials (HPAM) is proposed to enhance the functionality of Helmholtz-type resonators and porous materials, achieving continuous and efficient broadband sound absorption. This method can potentially eliminate absorption valley and improve the coupling strength through a synergistic energy dissipation mechanism and hybrid impedance matching behavior. Excellent sound-absorbing capability of the elaborately crafted HPAM was demonstrated analytically, numerically, and experimentally. Specifically, the results revealed an impressive average absorption coefficient of 0.77, with 73 % of the α points exceeding 0.8 across the entire test frequency range. Furthermore, the sound absorption of HPAM can be further optimized to attain ultra-broadband properties by modifying the hierarchical configuration and composite design of the porous materials. The physical mechanism is revealed through the integration of the hierarchical scaling effect and the energy-trapped mode. Numerical simulations revealed the emergence of three distinct absorption peaks at frequencies of 0.76, 1.4, and 3.6 kHz, respectively, and the effective absorption spectrum exceeded 3.4 kHz. Overall, the proposed design highlights the role of hierarchical structures and porous materials in synthesizing superior sound-absorbing properties that fully elucidate the relationship between structure and performance, and provide an avenue for potential noise-control applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microporous polymers are synthesized from triangular-shaped triazine monomers. • The polymers exhibit BET surface areas up to 1563 m2 g−1 and tunable pore sizes. • Methyl substituents result in interesting adsorption selectivity for C 3 H 8 /C 2 H 6 /CH 4 /CO 2. • Microporous characteristics remarkably affect adsorption of C 3 H 8 , C 2 H 6 , CH 4 and CO 2. • The adsorption selectivity is evaluated by breakthrough method. Microporous polymers (PAN-T1 and PAN-T2) with the similar polymer skeleton but considerably different BET surface areas from 1106 to 1563 m2 g−1, micropore surface areas from 250 to 868 m2 g−1 and total pore volumes from 0.84 to 1.09 cm3 g−1 were synthesized utilizing two planar triangular-shaped hexamines to polymerize with para -phthalaldehyde, respectively. The pores in PAN-T2 are quite uniform centering at 1.50 nm, whereas PAN-T1 exhibits the hierarchical pores consisting of ultramicropore (0.48 nm), micropore (1.05 nm) and mesopore (4.71 nm). Of interest is the finding that the high micropore surface areas are more advantageous for the adsorption of C 2 H 6 and C 3 H 8 than CH 4 and CO 2. The introduction of methyl substituents brings about the increased selectivities for C 3 H 8 /CH 4 , C 2 H 6 /CH 4 and CO 2 /CH 4 , but the selectivities of C 3 H 8 /CO 2 and C 2 H 6 /CO 2 exhibit an opposite trend. The effects of porosity parameters and chemical structure on the adsorption of CH 4 , C 2 H 6 , C 3 H 8 , CO 2, and the separations of binary mixtures for C 3 H 8 /CH 4 , C 2 H 6 /CH 4 , C 3 H 8 /CO 2 , C 2 H 6 /CO 2 and CO 2 /CH 4 are interpreted in terms of the variations in adsorption enthalpies, Henry constants, first virial coefficients as well as the polarizabilities, critical temperatures and sizes of the adsorbates. The results are helpful to deeply understand the pore-modulation mechanism in microporous polymers and the correlations of porous/chemical structures to the adsorption/separation of CO 2 and C 1 –C 3 light hydrocarbons in natural gas. [ABSTRACT FROM AUTHOR]

Analysis of the laminate's perforation resistance and the damage behavior is challenging due to the complex physical and geometric configurations. This work studied the mechanical behaviors both of carbon fiber reinforced plastic (CFRP) beam and square plate under transverse local load, including quasi-static indentation load and impact load. High-speed photography and non-invasive damage detective methods were used to capture specimens' dynamic deformation, damage process, and resultant damage. Experiment results indicate that the CFRP specimens of the beam shape show higher perforation resistance as well as more damage patterns than that of the square shape. In addition, it was validated through numerical simulations by considering the strain-rate effect with rate-dependent constitutive model compiled through subroutine VUMAT. [ABSTRACT FROM AUTHOR]

• Effect of projectile mass and dimension on CFRP laminates was investigated. • The study was conducted with diverse of the projectile mass and dimension. • The failure process and damage mechanism of CFRP laminates were revealed. The diverse mechanical properties and geometric configurations of the projectiles usually cause challenges to the accurate damage prediction of the carbon fiber reinforced plastic (CFRP) laminates. In this study, the mass and dimension of rigid projectiles are considered to explore their influence on the damage behaviors of CFRP, including dynamic deformation, fracture pattern, failure, etc. Experiments of different projectiles impacting on CFRP laminates are carried out, and a wide range of projectile kinetic energy (from 4.1 J to 548.4 J) are considered. The high-speed photography and non-invasive detection technique are used to capture dynamic fractures in CFRP laminates. Besides, a validated progressive damage numerical model is established for further investigation. The result indicates that the projectile dimension is associated with the penetration and delamination mode of CFRP, while the projectile mass affects dynamic deformation. [ABSTRACT FROM AUTHOR]

• A numerical model is established for simulating CFRP impacted by hail ice. • A damage threshold prediction model of CFRP impacted by ice ball is proposed. • A CFRP damage threshold can be derived at lower cost. Dynamic response mechanism of CFRP (Carbon Fiber Reinforced Polymer) panel under high-speed ice ball impact was challenging to elucidate due to inherent heterogeneity and anisotropy properties. This further leads to difficulties in theoretical prediction of the damage threshold. Simulation modelling of CFRP panel subjected to high-speed ice ball impact was conducted in this study. Through coupling SPH (Smoothed Particle Hydrodynamics) and FEM (Finite Element Method), the simulation has captured the deformation and damage of the CFRP panel and ice ball. A damage threshold prediction model of CFRP was then proposed based on the mechanism analysis of the dynamic deformation and delamination. The traditional prediction of CFRP impact damage threshold, that is, parametric studies on the damage threshold of CFRP panel influenced by different impact speed, ice ball diameter and panel thickness was performed. Finally, the results show that the CFRP damage threshold law obtained from parameterized simulation matches the previous experimental results, and a conservative damage threshold can be predicted from the proposed theoretical model. The proposed theoretical model can contribute to predicting the damage threshold of CFRP panels subject to ice ball impacts at low cost. [ABSTRACT FROM AUTHOR]

Sandwich panel with Honeycomb Filled with Circular Tubes (HFCT) as core is numerically investigated by using ABAQUS/Explicit in this study. To calibrate the numerical model, the panels equipped with conventional hexagon honeycomb cores are modeled. Good agreement between numerical and experimental results is achieved. The sandwich panels with HFCT are compared with the sandwich panels with Honeycomb and Multi-tube cores of identical mass subjected to vertical and oblique impacts. The maximum displacement of face-sheets, plastic energy absorption, boundary reaction forces and impact load time history are calculated to assess the impact resistant capacity. The panel with HFCT core has smaller rear face-sheet displacement and higher energy absorption capacity as compared to the panels with the Multi-tube and Honeycomb core. Under oblique impact, both HFCT and Multi-tube panels have superior impact resistant capacity than the Honeycomb panel. In addition, the impact resistances of four types of multi-arc tube filled Honeycomb (HFMT) are also analysed. Their performances under vertical and oblique impacts are compared with those of HFCT. [ABSTRACT FROM AUTHOR]

Abstract A series of fluorinated trans -porphyrins (1a-6a) bearing thienyl/biphenyl/naphthyl/fluorenyl/pyrenyl moieties were synthesized and characterized by various spectroscopic methods and electrochemical analysis. The scrambled products such as tetrakis(pentafluorophenyl)porphyrin, H 2 T(PFP)P and tris(pentafluorophenyl)-mono-(aryl) porphyrins (1b-6b) , obtained during the synthesis of these trans -porphyrins were also characterized. Four of the porphyrins were structurally characterized by single crystal XRD analysis. The luminescent oxygen sensing properties of the trans -Pt(II)-porphyrins were investigated in solution. Besides, the sensing properties of the complexes were compared in three different polymer films such as IMPEK-C, ethyl cellulose (EC) and poly(methylmethacrylate) (PMMA). The results revealed that the EC-porphyrin films show better sensitivity and good photostability than the other two films. The highest Stern-Volmer quenching constant of 0.096 Torr−1 was obtained for EC- Pt-3a which is 1.4 fold higher than the commonly used Pt(II)-(pentafluorophenyl)porphyrin. Graphical abstract trans-Pt(II)-porphyrins were examined for its oxygen sensing abilities on polymer matrices and EC-porphyrin films showed better sensitivity with good photostability than IMPEK-C and PMMA; the K SV value exhibited for EC-Pt-3a is higher compared to reference compound Pt(II)-(pentafluorophenyl)porphyrin. Image 1 Highlights • Fluorinated trans -porphyrins bearing thienyl/biphenyl/naphthyl/fluorenyl/pyrenyl moieties were synthesized and characterized. • The oxygen sensing properties of the Pt(II)complexes were compared in three different polymer films. • EC-porphyrin films show fast response, excellent sensitivity with good photostability than the other two films. • Introduction of two biphenyl moieties at the trans -positions of Pt(II)-TFPP improves the oxygen sensitivity by 1.4 fold. [ABSTRACT FROM AUTHOR]

[Display omitted] • A lattice design strategy of self-similar embedded hierarchical structure is proposed. • The influence mechanism of hierarchical configuration on plateau response is clarified. • The plateau response can be flexibly customized via multiple approach. Customizable stress plateau of lattice structure is sought-after for various engineering applications. In this study, we present a new design strategy to achieve customizable plateau, by introducing the concept of embedding self-similar structure in a face-centered cubic (FCC) lattice, which thereby constitutes a novel FCC hierarchical lattice (FCCH). These FCCH specimens were experimentally validated through quasi-static compression tests, on samples 3D-printed through selective laser melting using SS316L. These deformation characteristics were clarified by finite element analysis. The experimental and numerical results consistently show the serrated, dual, and upward plateaus were experienced for the 0th-order FCC, 1st-order FCCH, and 2nd-order FCCH structures, respectively. The mechanical reinforcements are based on the stronger interactions between unit cells induced by the embedded sub-structures. The deformation mechanisms dominated by hierarchical order are determined by horizontal layer-by-layer interaction as well as longitudinal buckling and collapse. The effect of geometric configuration show that stress plateau can be customized via optimizing different slave-cell sizes, connecting face-centers of lattice components, and arranging row layered gradient strategies. [ABSTRACT FROM AUTHOR]

Strain localization is a common phenomenon existing in various multiscale materials or structures, e.g., the bulking bands of thin-walled structures, the local collapse of porous materials, and the crack in solid materials, etc. However, this phenomenon cannot be captured by the conventional homogenization methods, such as mean-field homogenization (e.g., Mori–Tanaka method), first-order or high-order computational homogenization (e.g., the Finite Element Square method), etc., due to the high strain gradient associated with strain localization. Aiming at this, a hybrid Direct FE2 method is proposed by combining the D-FE2 (Direct FE2) and the traditional FE methods, while the multiscale structure is modeled using the D-FE2 method in the region exhibiting low deformation gradient, and the other region displaying high deformation gradient is modeled using the traditional FE method. Moreover, a node displacement constraint and an overall node displacement constraint derived from the multilevel equilibrium equations using the Gauss–Ostrogradsky theorem are respectively prescribed to the interface between the D-FE2 model and the FE model of the multiscale structure, to enforce the energy equilibrium and deformation continuity. The proposed hybrid D-FE2 method is then applied to predict the strain localization behavior of multiscale materials or structures, including local bulking of honeycomb structures, in-situ crack propagation, and localized plastic deformation in fiber reinforced composites, etc. Comparison of the simulation results obtained from the hybrid D-FE2 method and the traditional FE method validates the accuracy, efficiency and ease of numerical implementation of the proposed hybrid D-FE2 method. • A hybrid D-FE2 method was proposed for m ultiscale modeling of strain localization. • Displacement constraints were derived for d eformation continuity at the interface. • The hybrid D-FE2 method is accurate and more e fficient compared to DNS. [ABSTRACT FROM AUTHOR]

• Pre-impact significantly affects the flexural performance of CFRP sandwiches. • Analytical model and failure maps are constructed for collapse prediction. • The effects of impact energy and structural parameters are discussed. This study investigates the medium velocity impact response and post-impact flexural behavior of hybrid sandwich structures. A series of experiments are performed over a range of impact energies to evaluate the effect of structural parameters of sandwich beams on the impact damage and how impact damage affects the residual flexural strength. The experimental results show that the CFRP face sheets play a dominant role in the impact resistance of sandwiches. The impact-induced damage significantly reduces the residual flexural deformation of the sandwiches, as well as their bending strength and stiffness. A theoretical method is proposed to achieve deformation and failure mode prediction of post-impacted CFRP/aluminum-honeycomb sandwich beams. This work provides fundamental understandings on the relationship of pre-impact damages and residual flexural behaviors, so as to guide damage resistant design of composite sandwiches. [ABSTRACT FROM AUTHOR]

• A metamaterial incorporating the controllable coefficient of thermal expansion and auxeticity is proposed by introducing a bi-material double-square structure into the star-shaped cell. • The theoretical models based on the force method, exhibiting excellent consistency with the numerical results, are built to explore the mechanical and thermal responses of the metamaterial. • The desired properties of the proposed metamaterial can be customized by selecting the appropriate geometric and material parameters. • The metamaterial designed herein exhibits significant advantages in the auxeticity and thermal shrinkage under the identical relative density and dimension compared with the bi-material orthogonal-isotropic star-shaped metamaterial. This work proposes a novel metamaterial incorporating the auxeticity and thermal shrinkage by originally introducing a bi-material double-square into the star-shaped configuration. The theoretical modeling based on Mohr's theorem was built to predict its elastic and thermal properties. It shows excellent consistency with the numerical results, including the homogenized Young's modulus, Poisson's ratio, and coefficient of thermal expansion in three principal directions. The influence of the geometrical topology and material parameters on the elastic and thermal responses was clearly identified. The results suggest that desired properties of the metamaterial can be customized by reasonably modulating the appropriate geometric and material parameters. Compared with the orthogonal-isotropic star-shaped metamaterial with identical relative density and dimension, the design proposed in this study exhibits significant advantages in the auxeticity and thermal shrinkage. The plastic investigation suggests that this metamaterial also shows auxetic properties in large deformation. This metamaterial incorporating auxeticity and thermal shrinkage can be expected for applications such as smart actuators and satellite antennas with thermal stability. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The hybrid method of TPMS structures realizes the smooth transition of geometric surfaces as well as the complementary effects of elastic properties. • RVE-based homogenization method is used to efficiently calculate the elastic properties of hybrid TPMS. • A quadratic multi-parameter model is proposed to characterize hybrid modulus. • The TPMS hybridizations can be tailored through the diverse configurations and proportions of components. Hybrid design is an effective approach to construct functional mechanical metamaterials. In this study, a periodic hybrid method for the TPMS (triply periodic minimal surface) structures is proposed, maintaining the original surface connectivity and structural strength. It is implemented by the combination of implicit function Ψ (x , y , z) and transition function η x , y , z of the TPMS governing equation. Furthermore, three classical TPMS, i.e., P (Schwarz Primitive), IWP (Schoen I-WP) and FRD (Schoen F-RD), are represented to study the elastic properties of hybridizations using FE (Finite Element) computational method and experiments. Through the RVE-based (Representative Volume Element) homogenization method, it is demonstrated how hybridization of TPMS expands the designable range of elastic modulus. In addition, the elastic properties of the hybridizations, such as axial modulus, diagonal modulus and anisotropy, etc., can be quantificationally tailored by turning the formal parameters of TPMS. This study can be considered as a foundational contribution for the advancement of hybrid TPMS metamaterials. [ABSTRACT FROM AUTHOR]

The in situ effect on cross-ply laminates under out-of-plane shear loading is firstly studied with a two-dimensional RVE-based computational micromechanics method. High fidelity simulations of the interface de-bounding and crack propagation in laminates are performed, which shows good consistency with experimental observation. The matrix cracking behaviors and micro-mechanical response demonstrate that an in situ effect exists in cross-ply composites under out-of-plane shearing. Specifically, thinner ply laminates provide higher shear strength and stronger damage resistance due to the delay effect of transverse cracking and delamination. The analytical predictions on interlaminar shear strength of cross-ply laminates agree well with the existing theoretical criteria. A parametric study is performed to explore the possibility of acquiring stronger fiber-reinforced composites. The coupled load analysis sheds useful insights on the failure mechanism and optimization design of multi-layer composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microporous polymers decorated with phenyls, naphthyls and anthryls. • BET surface areas of polymers are up to 1229 m2 g−1. • Polymers possess modulated π-conjugation microenvironments. • Adsorption-desorption of C 2 H 6 and C 2 H 4 - are - reversible. • The selectivity adsorption of C 2 H 6 over C 2 H 4 is up to 2.70. Separation of ethylene (C 2 H 4)/ethane (C 2 H 6) is important yet extremely challenging task in petrochemical industry. Herein, three microporous polymers decorated with phenyls (PAN-P), naphthyls (PAN-NA) and anthryls (PAN-AN) were designed and synthesized in order to systematically study the correlations of the varied π-conjugation structure to the selective adsorptions of C 2 H 6 over C 2 H 4. The adsorption–desorption isotherms of C 2 H 6 and C 2 H 4 in the three polymers are completely reversible at room temperature. Moreover, it is interesting to find that at 298 K, among the three polymers, PAN-AN with the largest π-conjugation anthryl groups exhibits the highest C 2 H 6 /C 2 H 4 dynamic selectivity of 2.70. The different adsorption/separation behaviors of C 2 H 6 /C 2 H 4 in the three polymers are studied by means of the varied π-conjugation microenvironments as well as the porous characteristics such as specific surface areas, pore volumes and pore sizes and distribution. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel three-dimensional auxetic lattice is proposed by introducing a self-similar configuration into the vertex of the conventional re-entrant lattice. • The theoretical model for the elastic properties of the novel lattice is built and verified numerically and experimentally. • The novel lattice can possess the higher Young's modulus and exhibit the more comprehensive auxetic effect flexibility than the conventional re-entrant lattice with equivalent relative density. • The axial internal force in the struts inhibits the auxetic behavior of the novel lattice along the three principal axes. This work proposes a new auxetic lattice based on replacing the vertexes of traditional three-dimensional re-entrant structural with self-similar configurations. Derived by Castigliano's second theorem, a theoretical model is built to predict its elastic mechanical properties, including the homogenized Young's modulus and Poisson's ratio in all three principal directions. The overlapped nodes of struts are considered in the theoretical model due to their excessive strut thickness. The analytical results exhibit good agreement with the numerical and experimental results. The effects of the geometric parameters, internal force species, and hierarchical magnitude on the elastic property are carefully studied. The findings suggest that the axial internal force in the new structure inhibits its auxetic effects in the three principal directions. Compared with the traditional three-dimensional re-entrant lattice with equal relative density, the vertex-based hierarchical one exhibits more comprehensive designability of auxetic effect and enables higher Young's modulus with specific geometrical parameters. The findings in this study contribute to the metamaterial advancement and provide an option for engineering applications requiring programmable and controllable elastic properties. [ABSTRACT FROM AUTHOR]

Fractal-like structures have been found to offer excellent mechanical performance, showing remarkable potential in engineering applications. This study proposed the fractal-like honeycombs with different array configurations. Their intricate patterns were constructed based on a simple fractal cell inspired by Koch curve. Compressive behaviors of the proposed honeycombs were investigated theoretically and numerically. Compared with conventional honeycombs, the specific energy absorption (SEA) of the proposed honeycombs can be improved by 85%, 110% and 95% for triangular, square and hexagonal honeycombs, respectively. For every array configuration, the proposed structures all exhibit higher crushing force efficiency (CFE). Theoretical models of conventional honeycombs and the optimal fractal-like honeycombs were established. Folding mechanism was analyzed to reveal the mechanical improvement by comparing details of folding lobes in the forming process. Analytical solutions were compared in terms of the half-wave length, mean crushing force and SEA by a solution map, reflecting the ratios and trends of increment in each criterion. The influence of the cell number on the half-wave length was studied. The findings of this study provide new directions and guidelines for designing novel energy absorbers with enhanced crashworthiness. • Fractal-like honeycombs with different array configurations are proposed. • The novel honeycombs hugely outperform their conventional counterparts. • Lobes forming is analyzed regarding to folding efficiency and wall interactions. • Folding mechanism under the energy absorption enhancement is revealed. [ABSTRACT FROM AUTHOR]

For the topological diversity, in-plane hexagonal honeycombs show some interesting mechanical properties which can be related to Poisson's ratios. This work trying to understand how Poisson's ratios affects the crashworthiness of in-plane honeycombs. Based on the standard beam theory, the analytical model that predicting Poisson's ratios is derived, from which the crushing strength in terms of Poisson's ratios is further proposed by using one-dimensional shock model. Combining the analytical and numerical method, Poisson's ratios on the critical crushing characteristics as plateau stress, densified strain, Specific Energy Absorption (SEA) has been investigated under crushing speeds range from 5 m/s to 150 m/s which is complied with previous study about in-plane honeycomb crashworthiness. Through observing the wave trapping behavior of honeycombs, some typical deformation modes have been identified and a deformation-mode map is generated by considering critical wave trapping speeds and Poisson's ratio. • Established an evolution map of honeycombs with Poisson's ratio and correlated Poisson's ratio with topological diversity. • Derived the analytical model on dynamic plateau stress based on the one-dimensional shock theory. • The wave trapping capacity of honeycombs is investigated by deformation modes map with critical transforming speed. [ABSTRACT FROM AUTHOR]

The current research on bi-material diamond metamaterials, which can be used to program the coefficient of thermal expansion (CTE) over a wide range, mainly focuses on the theoretical design, while the corresponding experimental range of the CTEs is far narrower. In this study, a bi-material diamond metamaterial was additively manufactured using two polymers: nylon and polyvinyl alcohol (PVA). Without any need for extra processes such as bonding, welding, and mechanical fitting, the additively manufactured metamaterial integrated the nylon and PVA, providing an integrated fabrication process to ensure the expected programmable CTE. The experimentally measured CTEs agreed well with the theoretical predictions. When the material layout was selected as MAT-1 = PVA and MAT-2 = nylon, programmable CTEs ranging from 217.72 to 694.00 ppm/°C were obtained, which were larger than the CTEs of the nylon and PVA. When the material layout was MAT-1 = nylon and MAT-2 = PVA, even though both the nylon and the PVA had positive CTEs, a wide range of negative CTEs (varying from −25.02 to −369.01 ppm/°C) was obtained. The foregoing wide ranges of programmable CTEs are remarkably larger than the literature results, indicating the enhanced programmability of the bi-material metamaterial and stabilizing the foundation for the further design of multilevel and hierarchical metamaterials. Unlabelled Image • A bi-material metamaterial was additively manufactured with nylon and PVA without extra processes such as bonding or welding. • An experimental setup was developed to test the programmable CTE, and the results agreed well with theoretical predictions. • Positive programmable values as large as 217.72 and 694.00 ppm/°C were achieved for the CTE. • A wide range of negative CTEs [−25.02, −369.01] ppm/°C was experimentally obtained. [ABSTRACT FROM AUTHOR]

A crystalline porous bipyridine-based Bpy-COF with a high BET surface area (1864 m 2  g -1 ) and uniform mesopore (4.0 nm) is successfully synthesized from 1,3,5-tris-(4'-formyl-biphenyl-4-yl)triazine and 5,5'-diamino-2,2'-bipyridine via a solvothermal method. After Cu(I)-loading, the resultant Cu(I)-Bpy-COF remained the ordered porous structure with evenly distributed Cu(I) ions at a single-atom level. Using Cu(I)-Bpy-COF as a heterogeneous catalyst, high conversions for cycloaddition reactions are achieved within a short time (40 min) at 25 °C in water medium. Moreover, Cu(I)-Bpy-COF proves to be applicable for aromatic and aliphatic azides and alkynes bearing various substituents such as ester, hydroxyl, amido, pyridyl, thienyl, bulky triphenylamine, fluorine, and trifluoromethyl groups. The high conversions remain almost constant after five cycles. Additionally, the antiepileptic drug (rufinamide) is successfully prepared by a simple one-step reaction using Cu(I)-Bpy-COF, proving its practical feasibility for pharmaceutical synthesis., (© 2024 Wiley‐VCH GmbH.)

Characterized by periodic cellular unit cells, microlattices offer exceptional potential as lightweight and robust materials. However, their inherent periodicity poses the risk of catastrophic global failure. To address this limitation, a novel approach, that is to introduce microlattices composed of aperiodic unit cells inspired by Einstein's tile, where the orientation of cells never repeats in the same orientation is proposed. Experiments and simulations are conducted to validate the concept by comparing compressive responses of the aperiodic microlattices with those of common periodic microlattices. Indeed, the microlattices exhibit stable and progressive compressive deformation, contrasting with catastrophic fracture of periodic structures. At the same relative density, the microlattices outperform the periodic ones, exhibiting fracture strain, energy absorption, crushing stress efficiency, and smoothness coefficients at least 830%, 300%, 130%, and 160% higher, respectively. These improvements can be attributed to aperiodicity, where diverse failure thresholds exist locally due to varying strut angles and contact modes during compression. This effectively prevents both global fracture and abrupt stress drops. Furthermore, the aperiodic microlattice exhibits good damage tolerance with excellent deformation recoverability, retaining 76% ultimate stress post-recovery at 30% compressive strain. Overall, a novel concept of adopting aperiodic cell arrangements to achieve damage-tolerant microlattice metamaterials is presented., (© 2024 Wiley‐VCH GmbH.)

Introduction: This study aims to explore the important factors affecting the characteristics of different parts of pork., Methods: Lipidomics and proteomics methods were used to analyze DAL (differential lipids) and DAPs (differential proteins) in five different parts (longissimus dorsi, belly meat, loin, forelegs and buttocks) of Duhua pig (Duroc × Guangdong small spotted pig), to identify potential pathways affecting meat quality, investigating fat deposition in pork and its lipid-protein interactions., Results: The results show that TG (triglyceride) is the lipid subclass with the highest proportion in muscle, and the pathway with the most significantly enriched lipids is GP. DAP clustered on several GO terms closely related to lipid metabolism and lipogenesis (lipid binding, lipid metabolism, lipid transport, and lipid regulation). In KEGG analysis, there are two main DAP aggregation pathways related to lipid metabolism, namely Fatty acid degradation and oxidative phosphorylation. In PPI analysis, we screened out 31 core proteins, among which NDUFA6, NDUFA9 and ACO2 are the most critical., Discussion: PC (phosphatidylcholine) is regulated by SNX5, THBS1, ANXA7, TPP1, CAVIN2, and VDAC2 in the phospholipid binding pathway. TG is regulated by AUH/HADH/ACADM/ACADL/HADHA in the lipid oxidation and lipid modification pathways. Potential biomarkers are rich in SFA, MUFA and PUFA respectively, the amounts of SFA, MUFA and PUFA in the lipid measurement results are consistent with the up- and down-regulation of potential biomarker lipids. This study clarified the differences in protein and lipid compositions in different parts of Duhua pigs and provided data support for revealing the interactions between pork lipids and proteins. These findings provide contributions to the study of intramuscular fat deposition in pork from a genetic and nutritional perspective., Competing Interests: ZWa was employed by Guangdong Guanghong Agriculture and Animal Husbandry Development Co, Ltd. YL, LY, and JZ were employed by Guangdong Yihao Foodstuff Co, Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wu, Wang, Wang, Cheng, Li, Luo, Yang, Li, Zeng and Hu.)

Background: In recent years, studies on the clinical features and cognitive impairment of patients with different first-episode types of bipolar disorder have received increasing attention. The patients with bipolar disorder may present with different symptoms at first onset. The aim of this study is to assess the cognitive functions of a patient's index episode of bipolar disorder, depression or mania, on risk factors of effecting on cognitive functions., Method: One hundred sixty eight patients with bipolar disorder diagnosed for the first time were enrolled in the study. All patients were divided into two groups according to their index episode of bipolar disorder, either depression or mania. Seventy three patients of the cohort had an index episode mania and 95 patients had initial symptoms of depression. Demographic and clinical disease characteristic data of all enrolled patients were collected. Meanwhile, 75 healthy controls were included. Demographic data of controls were collected. The cognitive functions of all patients and controls were detected by continuous performance test (CPT), digital span test (DST) and Wisconsin card sorting test (WCST). The main cognitive functions data were compared among the mania group, depression group and control group. The relevant risk factors affecting cognitive function were analyzed., Results: (1) Most patients with bipolar disorder had an index episode depression (56.55% vs. 43.45%). Compared with the depression group, the mania group had later age of onset [(24.01 ± 4.254) vs. (22.25 ± 6.472), t  = 2. 122, p = 0.035]. The education level of patient groups was lower than control group ( p  < 0.001). (2) The healthy control group's DST, WCST and CPT scores were better than the patient groups (All p < 0.05). The mania group's DST (forward, reverse, sum), WCST (total responses, completed classifications, correct responses, incorrect responses, percentage of correct responses, completed the number of responses required for classification, the percentage of conceptualization level, the number of persistent responses, non-persistent errors), CPT (2 digit score, 3 digit score, 4 digit score) was better than the depression group ( p < 0.05). (3) In mania group, correlation analysis showed that all CPT parameter, inverse digit span, and the sum of DST was negatively correlated with the education level (All p < 0.05). The CPT-4 digit score was negatively correlated with onset age ( p < 0.05). In the WCST, the number of correct responses, the percentage of correct responses and the percentage of conceptualization level were positively correlated with the BRMS score (All p < 0.05). The number of false responses and persistent responses were negatively correlated with the BRMS score (All p < 0.05). The number of persistent errors and percentage of persistent errors was positively correlated with education years (All p < 0.05). In depression group, there was a positive correlation between inverse digit span and the education level ( p < 0.05)., Conclusion: In our study, there were cognitive impairments in attention, memory, and executive function of patients with different onset syndromes of bipolar disorder. Compared with the mania group, the degree of cognitive impairments in bipolar patients with the depressive episode was more severe. The risk factors affecting cognitive impairments included the age of onset, education level, number of hospitalizations and severity of illness., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Cao, Cao, Song, Jiang, Wei, Yang and Li.)

Two new carbazole-based monomers 6,6'-(9- n -butyl-9 H -carbazole-3,6-diyl)bis(1,3,5-triazine-2,4-diamine) and 6,6'-(9 H -carbazole-3,6-diyl)bis(1,3,5-triazine-2,4-diamine) are synthesized and employed to polymerize with formamide and N , N -dimethylformamide, respectively, to afford thee fluorescent micro-/mesoporous polyaminals with physicochemical microenvironment modulated by -NH 2 , -NH-, -N(CH 3 ) 2 , and n -butyl groups. Their chemosensing properties for five pesticides trifluralin (TFR), triflumizole, imidacloprid, lambda-cyhalothrin, and cyfluthrin are studied. Surprisingly, the polymers exhibit exceptionally high recognition for TFR, and the fluorescent quenching coefficients measured in water reach 4.1 × 10 6 M -1 , being 2 orders of magnitude higher than those of other porous polymers reported in the literature. The limit of detection (0.7 ppb) for TFR can compete with that of the electrochemical method. The fluorescence response at an extremely low concentration of 3 × 10 -8 M and selective recognition for TFR are confirmed by the visual observation using the portable polymer plates. Additionally, the different water mediums including varied acid-basic conditions and the presence of heavy metal ions have nearly no effect on the detection sensitivity. The ultrasensitive recognizable response for TFR is explained in terms of the photoinduced electron transfer, inner filter effect, improved hydrophilicity of polymer skeleton and porous trapping effect, and the dimensions and geometric configurations of pesticide molecules.

Objective: We conducted an updated coordinate-based meta-analysis (CBMA) to determine the most prominent and robust white matter (WM) abnormalities in ADHD based on tract-based spatial statistics (TBSS) findings., Method: The seed-based d mapping (SDM) software was applied to compare regional fractional anisotropy (FA) alterations in ADHD. Subgroup meta-analyses in the pure ADHD without comorbidity subgroup, the children and adolescents subgroup, and the adults subgroup were also explored, respectively. Meta-regression analysis was subsequently used to examine potential correlations between demographics and FA changes., Results: Only one cluster in the splenium of corpus callosum (CC) exhibited age-related FA decrease in ADHD individuals in the pooled meta-analysis. The adults ADHD subgroup revealed two clusters with reduced FA lied in the splenium and body of CC., Conclusion: This updated CBMA confirmed the WM abnormalities in the splenium of CC in ADHD, and improved our understanding of the pathogenesis of this neurodevelopmental disorder.

Although mutually independent, simultaneous sound absorption and superior mechanical properties are often sought after in a material. One main challenge in achieving such a material will be on how to design it. Herein, we propose a bamboo-inspired design strategy to overcome the aforementioned challenges. Building on top of the basic octet-truss design, we introduce a hollow-tube architecture to achieve lightweight property and mechanical robustness and a septum-chamber architecture to introduce acoustic resonant cells. The concept is experimentally verified through samples fabricated using selective laser melting with the Inconel 718 alloy. High sound absorption coefficients (>0.99) with broadband spectra, damage-tolerant behavior, high specific strength (up to 81.2 MPa·cm 3 /g), and high specific energy absorption of 40.1 J/g have been realized in this design. The sound absorption capability is attributed to Helmholtz resonance through the pore-and-cavity morphology of the structure. Microscopically speaking, dissipation primarily occurs via the viscous frictional flow and thermal boundary layers on the air and microlattice interactions at the narrow pores. The high strength is in turn attributed to the near-membrane state of stress in the plate structures and the excellent strength of the base material. Overall, this work presents a new design concept for developing multifunctional metamaterials.

Multifunctional materials are in high demand for practical engineering applications. Owing to the ubiquitous noise and impact energy hazards in many settings, traditional materials and conventionally designed metamaterials are incapable of preventing these types of hazard simultaneously. Herein, we report a new paradigm, via a decoupled approach, in the design of acousto-mechanical multifunctional metamaterials. We leverage the morphology of a Helmholtz resonator, such that the sound-absorbing and mechanical components are designed independently. For sound absorption, we adopt a coherent coupling design for a favorable resonant response, while for the mechanical response, we adopt customized struts. We then demonstrate our concept via 3D printing. Experimentally measured remarkable broadband absorption in the practical low-frequency range (<1.0 kHz) is achieved. Absorption mechanisms are attributed to viscous and thermal boundary dissipation. Compression tests also reveal that the metamaterials are highly deformation resilient with a recovery of up to 98%, owing to both the lattice structure design and the viscoelastic behavior of the base material. Through this decoupled design, we further demonstrate the potential of our metamaterials in customizable absorption, strength, pseudo-reusability, and impact resistance. The proposed design paradigm broadens the horizon for the design of multifunctional materials, offering an impetus to their exploration for practical applications.

Objective: Medical disorders in patients with bipolar disorder (BD) have attracted more and more attention. So far, there is still a lack of studies on this issue utilizing large sample sizes in the Chinese sample. Therefore, we conducted this study to explore the clinical characteristics of BD patients comorbid medical disorders in a relatively large Chinese sample., Methods: This was a cross-sectional study including 1,393 BD patients (882 patients with medical disorders and 511 patients without medical disorders). Their demographic and clinical characteristics were obtained by the Hospital Information System and self-designed questionnaires., Results: The comorbidity rate of medical disorders in BD was 63.32%. The average number of medical disorders for a BD patient was 2.69. The top five comorbid medical disorders in BD patients were circulatory system diseases (19%), nervous system diseases (18%), endocrine and metabolic diseases (17%), digestive system diseases (16%), and respiratory system diseases (8%). BD patients with comorbid medical disorders had an older average age, lower education level, longer illness course, later onset age, lower ratio of psychotic features, more admission numbers, higher ratio of smoking and drinking alcohol, more number of manic episodes (All P < 0.05). Smoking, numbers of depressive episode, onset age, and illness course were independent risk factors of comorbidities in BD patients (All P < 0.05)., Conclusions: Medical disorders in Chinese BD patients are highly prevalent. The smoking, number of depressive episodes, onset age, illness course, are correlated with BD patients comorbid medical disorders. Clinicians should pay attention to the medical disorders comorbidities in BD patients, and take effective measures to improve treatment outcome and reduce the suffering. The integrative approach should be the imperative in clinical practice., (© 2022. The Author(s).)

The residue of pesticides in crops, soil, and water continues to be a widespread concern due to the threat to human health and food safety. With the aim to develop highly sensitive sensing materials and portable detection devices, two dicarbazole-based fluorescent micro-/mesoporous polymers (JYs) with a larger specific surface area and pore sizes ranging from 1.1 to 34.2 nm are synthesized. The Stern-Volmer constants of JY fluorescence quenching for imidacloprid (50,063 M -1 ) exceed 23-51 times those of the reported porous organic polymers (980-2173 M -1 ). Of particular interest is the observation that JYs show rapid fluorescence response (2 s) and ultralow detection limit (30 ppb) for imidacloprid in water medium. The pronounced chemsensing property is attributed to the synergistic role of the hierarchical pore structure, large π-conjugation of chromophore groups, and strong inner filter effect between the polymer and imidacloprid molecule. Moreover, the pesticide detection of JYs exhibits good interference resistance in complicated service environments such as the extract liquids of the apple peel and field soil as well as aqueous solutions of various cations and anions. Because of the portability, excellent reusability, and sensitive fluorescence response, the prepared JYs and detection devices have promising applications in the on-site monitoring and early warning of the pesticide residues.

Background: The QTc interval may be significantly prolonged in schizophrenia patients taking antipsychotics. Few studies have addressed QTc prolongation (QTP) in Chinese patients. Objectives: This study was designed to evaluate the prevalence of QTP and its clinical correlates in Chinese hospitalized patients with chronic schizophrenia. Methods: A total of 436 inpatients and 291 normal controls matched with age and sex were included. QTc prolongation was defined as 2 standard deviations (SD) above the mean value of normal controls. Positive and Negative Syndrome Scale (PANSS) and its five-factor model were used to evaluate psychopathological symptoms. Results: QTc interval was significantly longer in patients than in normal controls. The prevalence of QTP is 8.26% in Chinese hospitalized patients with chronic schizophrenia. More women than men displayed QTP. Compared with patients without QTP, the patients with QTP had significantly higher concrete/disorganized subscore, lower low density lipoprotein (LDL) and lower total protein (TP). Furthermore, binary logistic regression analysis showed that higher number of hospitalizations, higher concrete/disorganized subscore and lower LDL were risk factors for QTP. Correlation analysis indicated significant association between QTc interval and the following variables: sex, age, duration of illness, the number of hospitalizations, PANSS total score, fasting blood glucose (FPG). Finally, a multiple regression analysis showed that older age, antipsychotic polypharmacy, higher PANSS total score, and lower LDL were risk factors for QTP. Among them, LDL seemed to be a protective factor for QTP. Conclusions: QTc interval was longer in schizophrenia patients than in normal controls. The prevalence of QTP is 8.26% in Chinese hospitalized patients with chronic schizophrenia. Some clinical characteristics were risk factors for QTP. And LDL seemed to be a protective factor for QTP., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Cao, Zhou, Li, Yao, Yang, Kong, Wang, Yu, Jiao, Sun, Jia, Wang, Wang, Zhang and Li.)

This paper presents a series of micro- and ultramicroporous polyaminals with BET surface areas up to 1304 m 2 g -1 , which are prepared from two triazine-based tetraamines and three dialdehydes or monoaldehyde through the A 4 + B 2 or A 4 + B 1 aminalization reaction. It is interesting to find that the para-substituted monomers are favorable to force the linking struts apart in the network to generate micropores (1.22 nm), whereas the meta-substituted monomers make the pores in the network squeezed by the twisted linking struts, resulting in the formation of ultramicropores (0.52 nm). Besides, the adsorption behaviors of the major components of natural gas, such as propane (C 3 H 8 ), ethane (C 2 H 6 ), methane (CH 4 ), and carbon dioxide (CO 2 ), are significantly different, strongly depending on the polarizabilities, critical temperatures, molecular sizes of gases, porosity parameters of polymers, and the interaction between gases and the polymer skeleton. At 298 K/1 bar, the polymers show high uptake for C 3 H 8 (114.5 cm 3 g -1 ) and C 2 H 6 (84.2 cm 3 g -1 ). Moreover, the adsorption selectivities of C 3 H 8 /CH 4 , C 2 H 6 /CH 4 , C 3 H 8 /C 2 H 6 , C 3 H 8 /CO 2 , C 2 H 6 /CO 2 , and CO 2 /CH 4 also reach 296.3, 23.1, 9.0, 22.1, 4.1, and 5.0, respectively, exhibiting promising applications in adsorption/separation of C 1 -C 3 hydrocarbons and stripping CO 2 gas from natural gas under the ambient condition.

Ultramicroporous semicycloaliphatic polyimides with major pore sizes less than 0.5 nm are synthesized through imidization reaction between different aromatic tetraamines and cycloaliphatic dianhydrides. The synergistic role of abundant CO 2 -philic imide rings and the molecular sieving effect of ultrasmall pores in the polyimide network bring about high adsorption selectivity of CO 2 /CH 4 (37.2) and CO 2 /N 2 (136.7). In addition, it is interesting to observe that, under ambient condition (298 K/1 bar), n-butane exhibits the highest uptake (3.15 mmol/g) among the C 1 -C 4 alkanes, and the adsorbed amount significantly drops with the reduction of the number of carbon atoms. As a result, the mixed light alkanes can be effectively separated according to the carbon numbers. The separation factors of n-butane/propane and propane/ethane reach 3.1 and 6.5, whereas those of n-butane, propane, and ethane over methane are as high as 414.5, 217.4, and 19.6, respectively. Moreover, the polyimides display large adsorption capacities for 1,3-butadiene (4.64 mmol/g) and propene (2.68 mmol/g) with good selectivity over 1-butene and propane of 3.2 and 3.0, respectively. Together with the excellent thermal and physicochemical stabilities, the ultramicroporous polyimides obtained in this work show promising applications in adsorption/separation for CO 2 , CH 4 , and C 2 -C 4 hydrocarbons.

A novel metal-doping strategy was developed for the construction of iron-decorated microporous aromatic polymers with high small-gas-uptake capacities. Cost-effective ferrocene-functionalized microporous aromatic polymers (FMAPs) were constructed by a one-step Friedel-Crafts reaction of ferrocene and s-triazine monomers. The introduction of ferrocene endows the microporous polymers with a regular and homogenous dispersion of iron, which avoids the slow reunion that is usually encountered in previously reported metal-doping procedures, permitting a strong interaction between the porous solid and guest gases. Compared to ferrocene-free analogues, FMAP-1, which has a moderate BET surface area, shows good gas-adsorption capabilities for H2 (1.75 wt % at 77 K/1.0 bar), CH4 (5.5 wt % at 298 K/25.0 bar), and CO2 (16.9 wt % at 273 K/1.0 bar), as well as a remarkably high ideal adsorbed solution theory CO2 /N2 selectivity (107 v/v at 273 K/(0-1.0) bar), and high isosteric heats of adsorption of H2 (16.9 kJ mol(-1) ) and CO2 (41.6 kJ mol(-1) )., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)