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In this study, a Finite Element (FE) model of locally strengthened high-strength stainless-steel tube subjected to lateral impact loads is established using LS-DYNA to investigate its dynamic behaviours. The accuracy of the FE results is verified by comparing with the test results. The impact force, bending moment, stress and strain responses as well as the internal energy dissipation histories of the strengthened tube are analysed during the entire impact process. The results indicate that the impact resistance of the strengthened tube is obviously enhanced as compared to hollow stainless-steel tube. Furthermore, parametric studies are conducted to reveal the influence of axial compressive force, impact position, impact velocity and material strength on the impact behaviour of the strengthened tube. The results show that the application of axial compressive force reduced the impact force and increased the deformations of the strengthened tube. The impact resistance of the strengthened tube performed an increasing trend when moving the impact position towards the support and increasing the material strength. In addition, the increase of impact velocity significantly reduced the impact duration. Finally, design recommendations and process were proposed to facilitate the application of locally strengthened tube. • The impact response of locally strengthened stainless-steel tube was numerically studied. • The impact force, bending moment, stress and strain response and energy dissipation were analysed. • Concrete was found to dissipate more impact energy than the other parts. • The effects of variant parameters on impact performances of the strengthened tubes were investigated. [ABSTRACT FROM AUTHOR]

Long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) is involved in the progression of Parkinson's disease (PD), but the specific regulatory role needs further exploration. This study showed that the expression of NEAT1 was upregulated in the cerebrospinal fluid (CSF) and peripheral blood of patients with different stages of PD. 1-Methyl-4-phenylpyridine (MPP)-treated PC 12 cells were transfected with si-NEAT1, and MPP treatment promoted cell apoptosis, oxidative stress and inflammatory factor secretion. Si-NEAT1 reversed the effects of MPP. NEAT1 silencing eliminated the effect of MPP on the protein expression levels of LC3-II and p62/SQSTM1. By using an online bioinformatics database, Fused in Sarcoma (FUS) was confirmed to be an RNA binding protein of NEAT1, and it was highly expressed in the CSF and peripheral blood of patients with PD. Si-FUS was transfected into MPP-treated PC 12 cells to detect cell apoptosis, oxidative stress, inflammatory factor secretion and autophagy, and the results were the same as those of transfection of si-NEAT1. Furthermore, MPP treatment reduced the phosphorylation levels of PI3K, Akt and mTOR, whereas si-FUS reversed the effects of MPP. In vivo , compared with the model group, the PD mice showed reduced NEAT1 and FUS expression levels and activated PI3K pathway after being injected with si-NEAT1. The brain tissue of NEAT1-silenced PD mice had decreased inflammatory infiltration and apoptosis and increased neurological scores. In conclusion, NEAT1 is involved in PD progression through FUS-mediated inhibition of the PI3K/AKT/mTOR signalling pathway. • LncRNA NEAT1 promotes PD progression. • FUS is an RNA binding protein of NEAT1. • NEAT1 promotes FUS expression. • NEAT1 inhibits PI3K/AKT/mTOR signalling pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel 3D N-doped carbon microspheres supported NiMo bimetallic catalyst was constructed. • Ni metal was uniformly dispersed with fine nanoparticles size (about 5.7 nm). • Synergistic effect of Ni, NiN x and MoO x sites endowed excellent nitrobenzene hydrogenation performance of the catalyst. • The catalyst showed a robust stability for no less than 6 cycles. • The catalyst exhibited outstanding universality for the hydrogenation of substituted nitroarenes. Reasonable modification of Ni-based catalysts is crucial for improving their catalytic activity in the nitroarenes hydrogenation but remaining a major challenge. Herein, a MoO x -promoted Ni-based bimetallic catalyst with fine Ni nanoparticles (only about 5.7 nm) anchored on N-doped carbon microspheres (NiMo 1 @NC-500) was prepared for the first time by a simple one-pot hydrothermal strategy and exhibits excellent catalytic activity for the probe reaction of nitrobenzene hydrogenation. The characterization and DFT calculations results elucidated that Ni and MoO 2 sites promoted the activation and adsorption of H 2 ; while the NiN x sites significantly enhanced the adsorption of the reaction substrate nitrobenzene. This synergistic adsorption mode endowed the catalyst with excellent nitrobenzene hydrogenation performance under mild conditions (80 °C, 1 MPa H 2 , 3 h). Moreover, the as-prepared catalyst exhibited robust stability for no less than 6 cycles and outstanding generality for the hydrogenation of other substituted nitroarenes, which provide a profound insight for the preparation of efficient and economical catalysts for the reduction of nitroarenes. [ABSTRACT FROM AUTHOR]

Novel itaconic acid-derived green hyperbranched macromers with polymerizable C=C bonds both in the internal skeleton and periphery were synthesized under mild synthetic conditions. The addition of hyperbranched polymers can make the cured cross-linked network denser and more uniform, and thus, leading to a significant improvement in performance of the coatings. [Display omitted] • Novel itaconic acid-based hyperbranched macromers with C = C bonds both in framework and periphery were designed and synthesized. • Esterification was catalyzed by tetramethylguanidine under mild reaction conditions with simple operations. • The new hyperbranched macromers can effectively promote the photopolymerization performance. • Addition of the hyperbranched macromers leads to a significant improvement in the performance of coatings. A series of hyperbranched polymers derived from biomass itaconic acid was prepared via aliphatic nucleophilic substitution polycondensation reaction under mild conditions by using bis(2-bromoethyl) itaconate and trimeric acid as A 2 and B 3 monomers, respectively, and tetramethylguanidine as catalyst. On this basis, the hyperbranched macromers that contained C = C double bonds in the internal skeleton and the periphery were obtained by further adding A 1 monomer (2-bromoethyl acrylate) directly into the reaction system. The successful synthesis of these macromers were confirmed via proton nuclear magnetic resonance, Fourier transform infrared and gel permeation chromatography. The results of photo-differential scanning calorimetry and rheological experiments showed that these macromers exerted a positive effect on the ultraviolet (UV) curing of commercial resin. The properties of cured splines and coatings, such as mechanical properties, pencil hardness, and thermal stability, were considerably improved with the addition of hyperbranched macromers. They were significantly better than those of linear macromers and macromers that contained polymerizable groups only in the inner framework or their terminal units. The results show that both the inner and terminal C = C double bonds of hyperbranched macromers can participate in UV cross-linking. Thus, such macromers may be used as potential additives for high-performance UV curable coatings. [ABSTRACT FROM AUTHOR]

Five novel iodonium salts (acceptors) and two amines (donors) can effectively form CTCs for photochemical/thermal initiators for single/two-photon photopolymerization. [Display omitted] • Iodonium salts and amines can effectively form CTC as novel long wavelength photoinitiators. • The newly photoinitiators are highly sensitive to UV–Vis LEDs @395–425 nm. • The optimized CTC can initiate radical polymerization as well as two-photon polymerization. • CTC have good performance as PIs and application prospects in the single/two-photon photopolymerization. Charge transfer complexes (CTCs), as a new type of photoinitiator system, exhibit excellent initiating abilities and are widely used in free radical polymerization. The reason is that it has safe photo or photo/thermal or dual initiator properties, which cannot be achieved by classical initiators. Thus, five novel iodonium salts (acceptors) and two amines (donors) capable of initiating thermal and photochemical polymerizations were investigated. The formations of the CTCs were assessed through their UV–visible (UV–vis) absorption spectra. The theoretical model study also attempted to show the relationship among the structure, reactivity, and efficiency of CTCs. Further explanation of the cause of this mechanism was provided by 1H NMR. The UV–vis photoinitiation ability of radical photopolymerization was also studied by real-time Fourier transform infrared spectroscopy and photo-DSC under LED@395–425 nm. The application of the newly developed initiating system in laser direct writing experiments at two-photon polymerization (780 nm) shows excellent spatial resolution performance. Such characteristic demonstrates that potential versatility can be applied in single/two-photon polymerization to manufacture high-precision materials. [ABSTRACT FROM AUTHOR]

• A new locally-strengthened method was developed for steel tube. • Impact tests were conducted on the locally-strengthened steel tube. • The failure mode, impact force, displacement and energy absorption were studied. • Analytical model was proposed to predict impact force and displacement responses. This paper proposes a novel stainless-steel tube locally strengthened by a concrete-filled steel tube to resist impact loads. A drop hammer impact test system was used to determine the failure modes, impact forces, and displacement responses of the strengthened tubes under an impact load. The effects of the strengthening length and thickness of the concrete and outer steel tubes on the impact responses of the strengthened tubes were investigated. The impact resistance was found to improve with an increase in the thickness of the concrete and outer steel thickness. The test results also indicated that the strengthened tubes exhibited a flexural failure mode with a combination of local and global deformations. An analytical model for predicting the dynamic responses of the locally strengthened tubes was established based on an equivalent two-degree-of-freedom (TDOF) model. The analytically predicted results were compared with the experimental results, and the good consistency between these two results demonstrated the accuracy of the established analytical model. [ABSTRACT FROM AUTHOR]

Diaryliodonium salts play an important role as highly efficient photoinitiators in the field of photopolymerizations. They can rapidly photodecompose to produce free radicals and super acids; thus, can initiate highly efficient photocuring of acrylic and epoxy monomers and resins. However, the absorption of commercialized diphenyliodonium salts is poorly matched with popular LED light sources, and the participation of sensitizers is usually required to achieve efficient photoexcitation. Here, we synthesized five new phenyl biphenyl iodonium salts with different electron-pushing and electron-withdrawing substituents, e.g., methoxy and CN, at the biphenyl substituent. Our results demonstrate that all synthesized iodonium salts have strong absorption in the range (λ max = 258–352 nm; ε max = 21,300–29,900 M−1 cm−1). The photochemistry of these synthesized iodonium salt is strongly influenced by substituents on the biphenyl ring. All iodonium salts can undergo rapid photolysis under light excitation, with higher quantum yield of photoacid generation reaching 0.25 and can quickly initiate cationic photopolymerization of epoxy monomers. Furthermore, free radicals are generated during photolysis, which can successfully trigger free radical polymerization. These iodonium salts with good absorbance in the UVA band demonstrate their potential as excellent photoinitiators under 365–405 nm LED excitation. Five long-wavelength LED sensitive iodonium salts with different substituents were designed and synthesized as photoinitiators for the photopolymerization process. [Display omitted] • Five push–pull biphenyl–based iodonium salts were designed and synthesized. • The photophysical and photochemical properties of iodonium salts are strongly influenced by substituents on the biphenyl ring. • The optimized iodonium salts are highly sensitive to UV–Vis LEDs @365–405 nm. • The iodonium salts can effectively initiate cationic/radical photopolymerization. [ABSTRACT FROM AUTHOR]

• A multilayer energy absorbing panel was proposed for impact resisting. • The deformation process and energy absorption behaviour were revealed. • Key parameters affecting responses of the energy absorbing panel were studied. • An analytical model was developed to calculate the displacement response. The enhancement of structural protection can be achieved by using energy absorbing structures as sacrificial layers. In this study, a new steel-PU foam-concrete-tube multilayer energy absorbing panel (SFCTMEAP) is developed to improve the impact resistance of buildings and infrastructures, and its behaviour under impact loading is numerically and analytically studied. A Finite Element (FE) model is established using LS-DYNA to further study the behaviours of SFCTMEAP, and its results (including the failure mode, displacement–time and impact force–time curves) agree well with the test data. The SFCTMEAP presents a deformation mode of local indentation of the front energy absorbing layer, flexure of the steel-concrete-steel panel and collapse of PU foam-filled steel tubes (PUFSTs). The energy dissipations of variant components of the SFCTMEAP are obtained through the FE model and the PUFSTs is the main energy absorbing component. In addition, parametric studies are performed to obtain the influences of the impact location, initial momentum of impactor and thickness of PU foam panel on the response of SFCTMEAP. The results indicates that the specimen with larger impact eccentric distance dissipates less impact energy, and raising the initial momentum of the impactor is benefit to the energy dissipation by the PUFSTs. Moreover, an analytical model is developed to calculate the displacement history of SFCTMEAP under the impact loading. The displacement responses predicted by the analytical model are found to be in good agreement with the test results. [ABSTRACT FROM AUTHOR]

Based on the controllability of the pore structure of perforated cenospheres (PCs), this study utilized PCs with different etching concentrations for the internal curing of alkali-activated slag (AAS), aiming to achieve the optimal etching parameters for efficient internal curing. Three etching concentrations (0.3 M, 0.7 M, 1.0 M) were set to investigate the effects of water-filled PCs on the performance of internal curing of AAS mortars. The results indicated that the water released from the PCs delayed the hydration of AAS and maintained high internal relative humidity. The chemical shrinkage of AAS could be reduced. Water-filled PCs internal curing promoted the generation of hydration products around the PCs and increased their packing density, leading to a reduction in mesopores and a 12.7—27.7% increase in elastic modulus at 28 d. With the optimal etching concentration of 0.7 M, water-filled PCs significantly mitigate the autogenous shrinkage by 75.8% while enhancing the compressive strength of AAS mortars. • Three etching concentrations of perforated cenospheres (PCs) were investigated for the internal curing efficiency of AAS. • PCs internal curing increased the internal relative humidity and reduced the chemical shrinkage. • PCs internal curing enhanced the packing density and elastic modulus of hydration products. • The optimal 0.7 M etching concentration reduced autogenous shrinkage by 75.8% and enhanced compressive strength. [ABSTRACT FROM AUTHOR]

• The response of vegetation to drought in Central Asia (CA) is nonlinear. • The responses of four vegetation indices to drought in CA were compared. • Spatial patterns of vegetation responses to drought in CA were quantified. • Lagged effect of drought on vegetation in CA was greater than cumulative effect. Central Asia (CA) is an arid region sensitive to climate change, and with the increase in drought events due to global warming, droughts are posing more severe threats to the vegetation in CA. However, the response of vegetation in CA to the cumulative and time-lag effects of prolonged drought remains unclear. This has limited our understanding of the mechanisms by which vegetation responds to meteorological drought in arid regions. To clarify the response of vegetation to drought in CA, this study analyzed the effects of drought and meteorological factors on vegetation growth dynamics. The extent of vegetation response to the cumulative and time-lag effects from 2001 to 2020 was evaluated using three satellite-derived vegetation indices (NDVI, EVI, NIRv) and the solar-induced chlorophyll fluorescence (SIF) and standardized precipitation evapotranspiration index (SPEI). We used the Copula-Bayes conditional probability method to assess the drought thresholds for vegetation under two scenarios: mild and severe losses. The effects of soil moisture (SM) and vapor pressure deficit (VPD) on vegetation dynamics were analyzed based on an improved partial wavelet coherence (PWC). The results show that the average response time of vegetation to the cumulative and lagged effects of drought was mostly concentrated within 4–6 months, and the lagged effect was stronger than the cumulative effect. The vegetation response to drought is nonlinear along the precipitation gradient. The SPEI values for triggering mild vegetation loss (below the 40th percentile) drought threshold range from −0.7 to −1.0, while the SPEI values for triggering severe vegetation loss (below the 10th percentile) drought threshold range from −2.0 to −2.5. The SM was the main driver affecting vegetation dynamics. This study provides deeper insight into the response of vegetation to drought in the arid zone of CA, which will further provide theoretical support for addressing global climate change and extreme drought events. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the influence of gallic acid (GA), the smallest molecular unit of tannic acid, on the performance of metakaolin (MK) mortars. GA was added directly as an admixture (Method I) or pre-mixed with MK (Method II) for bio-functionalization. Experimental results showed that GA improved the dispersion of MK by generating electrostatic repulsion and spatial site resistance between particles. The GA functionalization of MK by Method II displayed superior efficiencies in adjusting the fluidity of mortars owing to better dispersibility. The functionalization of MK by GA could enhance the pore filling effect resulting from the dispersed MK, and enable more products to be generated owing to the formation of GA ∼ Ca intermediates, contributing refined pore structure and increased compressive strength to mortars. The compressive strength of MK mortars has been optimally increased by 13.0—18.0% when using 0.1% GA. • Two bio-functionalization methods for MK were proposed. • GA promoted mortar hydration by dispersing MK and GA ∼ Ca seed. • GA functionalized MK reduce the porosity of mortars by filling the pores. • Method II achieved better fluidity and higher compressive strength than Method I. [ABSTRACT FROM AUTHOR]

Two twisted π-conjugated cruciform luminophores MDCS-TPA and FMDCS-TPA containing two conjugated donor and acceptor groups intersecting at the central benzene core have been rationally designed and successfully prepared. The two compounds display unique intramolecular charge-transfer (ICT) process from electron-rich triphenylamine and electron-poor cyanostyryl units, which are evidenced by theoretical calculations and spectral analysis. MDCS-TPA and FMDCS-TPA exhibit AIE effects with high fluorescence quantum yields of 0.321 and 0.312 in the solid state. Interestingly, MDCS-TPA and FMDCS-TPA possess the distinct mechanofluorochromic (MFC) behavior. The as-prepared powders of the two luminophores could emit strong green (491 nm) and yellow-green fluorescence (529 nm), and the fluorescence color changed into yellow (542 nm) and orange (576 nm) after grinding, respectively, giving the red shifts of 51 nm and 47 nm. Such mechanochromism is reversible by repeating both the grinding-fuming and grinding-annealing processes. The MFC behavior of MDCS-TPA and FMDCS-TPA originates from the transition between the crystalline and amorphous states and the red-shifts induced by grinding is the result of the planarization of the molecular conformation and subsequent planar intramolecular charge transfer (PICT) under the external force stimuli. Image 1 1 Two twisted π-conjugated cruciform luminophores displayed a unique ICT process. 2 They exhibited AIE effects with high fluorescence quantum yields in the solid state. 3 They showed high contrast mechanofluorochromic behavior with good reversibility. [ABSTRACT FROM AUTHOR]

• A new multilayer energy absorbing panel was developed. • Impact tests were conducted on the energy absorbing panel. • The failure mode, impact force, displacement and energy absorption were studied. • An analytical model was proposed to predict the displacement response. A novel steel-polyurethane foam-concrete-tube multilayer energy absorbing panel (SFCTMEAP) was proposed in this paper, and it could be attached to the surface of the protected structure to mitigate impact loading. The impact tests on the SFCTMEAP were performed via using a drop-weight impact test machine. The investigated parameters in the impact tests included the thickness of concrete core as well as thickness and width of the steel tube. All tested specimens exhibited a combined failure mode, consisting of the local indentation of energy absorbing panel and the collapse of polyurethane foam-filled steel tubes. The energy absorbing performance of SFCTMEAP under impact loading was discussed in detail. Additionally, a three-degree-of-freedom model was proposed to obtain the displacement response of the SFCTMEAP, and the analytically-calculated displacement–time histories agreed well with the experimental results. [ABSTRACT FROM AUTHOR]

• A steel–concrete-steel sandwich panel with energy absorbing supports (SSP-EAS) was developed for impact resisting. • The impact resistant performances of the SSP-EAS were experimentally and numerically investigated. • Impact response modes and failure modes of the SSP-EAS were studied. • The effects of crushing force of EAS and initial impact momentum on impact behaviors of the SSP-EAS were analyzed. A new steel–concrete-steel sandwich panel with energy absorbing supports (SSP-EAS) was firstly proposed, and its dynamic responses under impact loading were investigated through conducting impact tests and numerical simulations. Three types of impact response modes of SSP-EASs were categorized according to the different crushing magnitudes of energy absorbing supports (EASs). In addition, the steel–concrete-steel sandwich panel (SSP) exhibited the combination of the global flexural deformation, local indentation and local bulging during the impact. The EAS could effectively absorb impact energy through the plastic bending of steel plates and the crushing of aluminum foam blocks, except for the response mode I with insignificant crushing of EASs. Moreover, the effects of crushing force of EASs and initial impact momentum on the dynamic responses of SSP-EAS were numerically analyzed. The impact resistance of the SSP-EAS could be improved through properly designing the EAS and assuring its maximum displacement slightly smaller than the compaction displacement during impact. In addition, the crushing force of EAS should not exceed the ultimate resistance of the SSP to assure the EAS being triggered to crush. Moreover, the SSP-EAS exhibited enhanced impact performances under higher initial impact momentum. [ABSTRACT FROM AUTHOR]

• The combination of MgO and fly ash effectively solidifies salt-bearing clay in areas subjected to seasonal freeze–thaw cycles. • The substitution of conventional solidifying materials with fly ash constitutes a sustainable and ecologically responsible approach to consolidating clay soils. • The cementation of soil particles is efficiently accomplished by the carbonate compounds generated from magnesium and calcium. This paper presents an innovative method for improving the strength of salt-bearing clay under freeze–thaw cycles. The active magnesium oxide (MgO) and industrial waste fly ash were employed as primary solidifying materials in the seasonal freezing soil reinforcement process, and the reinforcement effect is achieved through carbonate crystals generated through carbonization tests. The solidification effect was investigated with varying ratios of solidifying materials, salt content, and freeze–thaw cycles. The experiment results revealed that the combination of active MgO and fly ash effectively enhances the strength of salt-bearing clay. Specifically, compared to unsolidified soil, the soil solidified with 8 % active MgO (8M0F) and a combination of 4 % active MgO and 4 % fly ash (4M4F) demonstrated a significant increase in ultimate strength by 14 and 12 times, respectively. Moreover, the number of freeze–thaw cycles exhibited a negative correlation with ultimate strength, whereas the salt content demonstrated a similar negative correlation. Microscopic analysis revealed that the 8M0F sample produced mainly magnesium carbonates and hydrogen and oxygen compounds, whereas the 4M4F sample generated primarily magnesium and calcium carbonates. The resulting compound crystals efficiently filled the internal pores and cemented the soil particles, leading to a substantial increase in strength. Overall, these results indicate that the active MgO combined with fly ash solidifying method can offer a viable and sustainable solution for improving the strength of salt-bearing clay in areas with seasonal freeze–thaw cycles. [ABSTRACT FROM AUTHOR]

The steel–concrete–steel (SCS) sandwich structures are increasingly adopted to improve the impact resistance of the buildings or infrastructures owing to their good structural performances. Recently, the SCS sandwich beams with interlocked angle connectors (SCSSB-IACs) have been developed, and their performances under impact loading have been experimentally studied. This paper presents detailed numerical analyses of the SCSSB-IACs subjected to impact loading and reveals its response mechanisms. The Finite Element (FE) models of the SCSSB-IACs were established using LS-DYNA, and the FE predictions showed a good agreement with the impact test data. The impact process as well as distribution and evolution of bending moment and shear force, stress and strain were discussed. Furthermore, the internal energy histories of the SCSSB-IACs were revealed by FE analyses. Numerical results indicated that the majority of impact energy was absorbed by the concrete and bottom faceplate, and the deformation of the SCSSB-IACs was dominated by a flexural manner. Finally, parametric studies were performed to reveal the effects of impact momentum, energy and location on the response of the SCSSB-IACs. • FE models of the steel-concrete-steel sandwich beam with interlocked angle connectors (SCSSB-IACs) were established. • The accuracy of FE models of the SCSSB-IACs was validated with experimental results. • The internal force distributions, strain and stress responses and energy response of the SCSSB-IACs were discussed. • Parametric studies were conducted to further reveal the failure mechanisms of SCSSB-IACs. [ABSTRACT FROM AUTHOR]

Highlights • The experimental data of R134a pool boiling on a novel reentrant cavity tube was obtained. • The heat transfer enhancement factor for the enhanced tube peaked in the heat flux range was founded. • The boiling Nusselt number and Reynolds number was used to describe the heat transfer characteristics. • Correlations were developed to predict the experimental data within 4%. Abstract This study experimentally investigated pool boiling heat transfer performance on horizontal copper tubes with refrigerant R134a. Experiments were conducted at saturation temperature of 5.6℃, while heat flux varied from 5 to 65 kW/m2 with an interval of 5 kW/m2. A plain tube and a reentrant cavity tube (enhanced tube) were tested. The nominal outside diameter of test tube was 25.14 mm and the length in test section was 1000 mm. Tubes were water heated by 15% volume faction water-ethylene glycol mixture with an insert bar in the fluid passage. The experimental data of the plain tube were compared against the Cooper correlation with deviation of −3% to −10%. The boiling heat transfer coefficient of the enhanced tube increased with the increasing heat flux in the experimental range. The heat transfer enhancement factor, the ratio of boiling Nusselt number for enhanced tube to that for plain tube, varied from 1.66 to 2.64 and reached the maximum at Re o = 0.38(heat flux q = 20 kW/m2). The boiling Nusselt number was correlated with boiling Reynolds number with predicting the experimental data within ±4%. [ABSTRACT FROM AUTHOR]

Abstract Steel-concrete-steel (SCS) sandwich shells, which are combined with steel plates, concrete core and shear connectors, are usually applied as protective structures in the civil engineering. In this paper, nine curved SCS sandwich shells subjected to concentrated load by a hemi-spherical head were tested to obtain the failure characteristic, ultimate strength and load–displacement response. The finite element (FE) models of curved SCS sandwich shells were also established by using LS-DYNA. The accuracies of the FE models were verified by comparing the load–displacement curves, local and global deformation between the experimental results and FE predictions. The factors influencing the ultimate strength and deformation behavior of curved SCS sandwich shells were analysed, including concrete core and steel plate thickness, top to bottom steel plate thickness ratio and spacing of shear connectors. Through experiments and numerical simulations, three failure modes could be summarized. It was also found that increasing concrete core and top steel plate thickness and reducing the spacing of shear connectors could increase yield strength and ultimate strength of curved SCS sandwich shell. The increase of concrete core and steel plate thickness also led to higher energy absorption capacity; whereas, the spacing of shear connectors showed little effect on energy absorption capacity. Highlights • Nine curved SCS sandwich shells subjected to concentrated load were experimentally studied. • Failure modes of curved SCS sandwich shells were summarized. • Parameters affecting the strength of curved SCS sandwich shells were discussed. • The FE analysis was conducted to reproduce the experimental observations. [ABSTRACT FROM AUTHOR]

Highlights • The different camera system calibration and matching are simultaneously achieved. • The fusion of 3D digital model to 2D IR image reaches up to sub-pixel accuracy. • Integration active thermography and 3D optical imaging is used for the 3D visualization of defects. Abstract In this paper, a combination active thermography and three-dimensional (3D) structural optical imaging is reported on the nondestructive inspection of curved clad composites with subsurface defects. Artificial points are marked on the background of test objective and helpful to obtain the mapping matrix from two-dimensional (2D) thermal wave characteristic imaging data to 3D spatial coordinate's digital model. The 3D digital model is transformed into a new coordinate system and then reprojected onto the thermal-wave feature image exactly. The fusion of 2D thermal-wave characteristic data and the 3D digital model is achieved by bilinear interpolation. Specimens of carbon fiber reinforced polymer (CFRP) skin-honeycomb sandwich (CFRP-SHS) and High silicon oxygen phenolic resin (HSOPR) sheet with artificial defects are prepared for the experimental investigation. Experimental results indicate that the proposed method can reliably inspect the defects and accurately locate defect positions on the curved surface of CFRP-SHS and HSOPR laminate test sample, and it has a significantly potential for the use of aerospace and aircraft manufacturing and application. [ABSTRACT FROM AUTHOR]

In this paper, the drop-weight impact loading tests were conducted to study the dynamic crushing behaviors of the proposed energy absorption connectors with curved plate and aluminum foam as energy absorber. The dynamic collapse modes of the connectors were obtained from the tests and three deformation processes were identified. The effects of loading rate, filled aluminum foam, curved plate thickness and radius on the energy absorption performances of the connectors were quantitatively evaluated, which showed that filling the connector with aluminum foam as well as increasing loading rate, curved plate thickness and radius generally led to increase of energy absorption capacity of the connector. Besides the experimental works, the numerical and analytical models were also developed to predict the force–displacement responses of the connectors and the accuracies of the two models were validated against the test results. The developed analytical model could be utilized as a convenient tool to quickly evaluate the energy absorption performances of such connectors under impact loading. [ABSTRACT FROM AUTHOR]

In this paper, the energy absorption performances of the aluminum foam filled connectors under drop-weight impact loading were first evaluated via using experimental method. The dynamic crushing behaviors of the connectors were examined and three deformation processes were identified from the experiments. The effects of loading rate, filled aluminum foam, pleated plate thickness and angle θ o (the angle between flat plate and pleated plate) on the energy absorption performances of the connectors were experimentally investigated, which showed that the energy absorption capacity was improved by filling the connector with aluminum foam as well as increasing loading rate, pleated plate thickness and angle θ o . Moreover, the numerical and analytical models were also developed to predict the force–displacement responses of the connectors, which showed good agreement with the test results. The developed analytical model could be used as a convenient tool to quickly evaluate the energy absorption performances of such connectors under impact loading. [ABSTRACT FROM AUTHOR]

Two twisted donor–acceptor cruciform luminophores ( DHCS-TPE and DMCS-TPE ) that were composed of two π-conjugated segments connected via a central benzene core have been prepared. Such cruciforms showed unique intramolecular charge transfer (ICT) emission, obvious aggregation-induced emission (AIE) properties (α AIE  = 19 and 20, respectively) and high solid state efficiency (0.913 and 0.424, respectively). Especially, the two compounds exhibited substituent-dependent mechanofluorochromic (MFC) behavior. The as-prepared powders of the more twisted DMCS-TPE could emit strong blue-green light centered at 474 nm, and the fluorescence color changed into yellowish green (531 nm) after grinding, a red shift of 57 nm was observed. Such mechanochromism was reversible upon the treatment of grinding and fuming with DCM. The high contrast MFC behavior of DMCS-TPE originated from the planarization of the molecular conformation and subsequent planar intramolecular charge transfer (PICT) under external force. By sharp contrast, the less twisted DHCS-TPE exhibited no MFC behavior. The reason is that the less twisted molecular conformation of DHCS-TPE generates strong intermolecular forces and close packing. Thus compared to DMCS-TPE , the crystalline solid powders of DHCS-TPE possess higher lattice energy and better structural stability. The grinding of the crystalline solid powders of DHCS-TPE cannot lead to amorphization and mechanochromic luminescence. [ABSTRACT FROM AUTHOR]

This study explored the impact responses of a steel–concrete–steel sandwich composite panel with novel interlocked angle connectors (SCSP-IACs). Impact tests on nine SCSP-IACs were performed via a hemispherical hammer. The failure modes of all specimens were determined as the local punching failure of the concrete core. Moreover, the impact force–time and displacement–time histories and the permanent deformation were discussed. The experiment results showed that increasing the steel faceplate thickness and concrete core height enhanced the impact performance of the SCSP-IACs. By contrast, increasing the IAC spacing weakened the impact performance. Moreover, the interlocking bolts slightly affected the impact responses of the SCSP-IACs. A finite element (FE) model was established and verified with test data. The model was used to analyze the internal forces and energy absorption of the SCSP-IACs under impact loads. The internal force diagrams of the panels at different impact stages were provided, and a significant hogging moment was observed from the bending moment distributions. The FE results also showed that the zones close to the center of the panel absorbed most of the impact energy. • A novel SCS panel with interlocked angle connectors (SCSP-IACs) was proposed. • The effects of variant parameters on impact responses of SCSP-IACs were studied. • Distributions of internal forces of SCSP-IACs under impact loads were revealed. • The variations of energy absorption in different zones of SCSP-IACs were presented. [ABSTRACT FROM AUTHOR]

Recent studies proposed a convergence in the temperature sensitivity (Q 10 ) of soil respiration (R s ) after eliminating confounding effects using novel approaches such as Singular Spectrum Analysis (SSA) or the mixed-effects model (MEM) method. However, SSA has only been applied to eddy covariance data for estimating the Q 10 with air temperature, which may result in underestimations in responses of below-ground carbon cycling processes to climate warming in coupled climate-carbon models; MEM remains untested for its suitability in single-site studies. To examine the unconfounded Q 10 of R s , these two novel methods were combined with directly measured R s for 6 years in two Tibetan alpine ecosystems. The results showed that, 1) confounded Q 10 of R s estimated from seasonal R s -temperature relationship positively correlated with the seasonality of R s , and 2) estimates of unconfounded Q 10 of R s using SSA (mean = 2.4, 95% confidence interval (CI): 2.1–2.7) and MEM (mean = 3.2, 95% CI: 2.3–4.2) were consistent with the theoretical subcellular-level Q 10 (≈2.4). These results support the convergence in the Q 10 of R s and imply a conserved R s -temperature relationship. These findings indicate that the seasonality of R s has to be eliminated from estimating the Q 10 of R s , otherwise the estimates should be questionable. They also indicate that seasonal Q 10 and its responses to warming should not be directly used in carbon-climate models as they contain confounding effects. [ABSTRACT FROM AUTHOR]

This paper presents the experimental and numerical studies on the thermal responses of precast concrete sandwich (PCS) walls with a novel hybrid connector. The hybrid connector is wrapped with nylon, which is shown to reduce the thermal bridge and improve the thermal performance of PCS wall. In the first part of this work, four PCS walls were fabricated for the experimental studies and the effects of hybrid connector, insulation layer thickness and insulation material on the thermal performances of PCS walls were experimentally evaluated. Then, the finite element (FE) method was adopted to conduct the heat transfer analyses on PCS walls. The accuracies of the FE models were verified via comparing the temperature and thermal transmittance versus time of PCS walls obtained from experiments and FE analyses. The FE models were subsequently used to investigate the effects of wrapped nylon, thermal conductivity, connector spacing, central rebar diameter and insulation layer thickness on the thermal performance of PCS walls. It was found that the thermal performance of PCS wall could be improved via wrapping the connector with nylon, reducing the materials’ thermal conductivities, increasing connector spacing and insulation layer thickness as well as reducing central rebar diameter. [ABSTRACT FROM AUTHOR]

How graphene oxide (GO) derivatives might affect the cell cycle has been rarely studied. Herein, a GO derivative was fabricated by functionalization of GO with polyethylene glycol (PEG) and polyethylenimine (PEI), and its cytotoxic mechanism was investigated in-depth. It was found that our obtained GO-PEG-PEI nanosheets, not the cytotoxic coating polymer PEI, could induce defect in S phase of the mammalian cell cycle, resulting in decreased DNA synthesis, S phase arrest, and abnormal cytoskeleton structure. Further analysis demonstrated that this damaging effect on S phase could be detected in all five tested mammalian cell lines. Even at seemingly safe concentration (∼90% cells viable), GO-PEG-PEI could still induce S phase defect. Detailed investigations revealed that GO-PEG-PEI could cause genomic DNA damage, activating the intra-S-phase checkpoint control via both the ATM and the ATR signaling pathways. Our work unveils the signaling pathways involved in the interaction of GO-PEG-PEI with mammalian cells, and highlights the necessity and importance of comprehensive investigations of the effects of nanomaterials on cellular pathways, such as the cell cycle in this case, even for those with seemingly little/low cytotoxicity during preliminary evaluations. Our work also highlights the critical roles of surface chemistry in biological effects of nanomaterials. [ABSTRACT FROM AUTHOR]

• A SCS panel with energy absorption connectors (SCS-EC) was proposed for impact resisting. • Drop-weight impact tests and Finite Element simulations were conducted on the SCS-EC. • Failure modes and impact responses of the SCS-EC were obtained. • The effect of variant parameters on impact response of the SCS-EC was analyzed. This paper developed a new steel-concrete-steel sandwich panel with energy absorption connectors (SCS-EC) for resisting impact load, and the impact responses of the SCS-EC were studied by conducting impact tests and Finite Element (FE) simulations. The failure modes of the SCS-EC under impact loading could be categorized into two types based on the crushing magnitude of the energy absorption connector (EC). The EC was found to effectively dissipate impact energy via the plastic deformation of pleated steel plates and the compression of aluminum foam fillers. The steel-concrete-steel (SCS) panel showed the combination of global and local deformation under impact loading. Moreover, the influences of pleated plate thickness (t p) and angle (θ p), aluminum foam filler and initial momentum on the impact performances of the SCS-EC were studied quantitatively. The results showed that the SCS-EC exhibited enhanced impact resistance via increasing initial momentum of the impactor as well as filling aluminum foam in the EC and assuring the maximum crushing displacement of the EC being equal to its densification displacement. [ABSTRACT FROM AUTHOR]

In this study, a novel multi-cell steel–concrete–steel (MCSCS) sandwich panel was proposed for enhancing impact resistance of the traditional steel–concrete–steel​ (SCS) sandwich panel. The MCSCS sandwich panel employed stiffeners and headed studs to improve the bonding behavior between faceplates and concrete core as well as enhance its composite action and impact resistance. Impact tests were conducted on seven MCSCS panels via employing a drop weight loading system, and the influences of impact direction, spacing of headed stud and steel plate thickness on responses of MCSCS panels were investigated. Furthermore, the Finite Element (FE) model of the MCSCS panel was established, and the FE predictions were shown to be reasonable as compared to test results. Two types of failure modes of MCSCS panels under impact load were obtained via analyzing the test and FE results. In addition, based on the verified FE model, the influences of stiffeners, impact location and curvature of hammer head on impact responses of MCSCS panels were revealed via parametric studies. The results of FE simulations indicated that the impact location and curvature of hammer head had evident effect on the energy absorption and impact response of the MCSCS panel. Moreover, owing to the employment of stiffeners, the impact resistance of the MCSCS panel was evidently enhanced as compared to the traditional SCS panel. • A novel multi-cell steel–concrete–steel (MCSCS) sandwich panel was proposed. • The influences of critical parameters on impact responses of MCSCS sandwich panels were analyzed. • The energy dissipation mechanism of the MCSCS sandwich panel was revealed. • Combined with the inertial force, a clear definition of the inertial stage in the impact process was given. [ABSTRACT FROM AUTHOR]

This paper presents a new steel–concrete–steel sandwich panel with interlocked angle connectors (SCSP-IACs), and its punching performances were experimentally and analytically studied. Nine SCSP-IACs were fabricated and tested under the out-of-plane patch loads. Test results showed that SCSP-IACs exhibited two types of load–deflection (P – δ) responses with the variation of spacing of IACs (S), and increasing S also showed significantly negative influences on their punching behaviors. Two peak resistances were observed from the P – δ curves of all SCSP-IACs, and the first and second peak resistances (P u1 and P u2) corresponded to the punching shear failure of the concrete core and top steel faceplate, respectively. The punching shear resistance of SCSP-IACs was found to be evidently improved with the increase of steel faceplate thickness (t s) and concrete core thickness (d), while increasing S led to the decrease of punching shear resistance of SCSP-IACs. Moreover, the interlocking bolt in IACs exhibited little influence on the punching behaviors of SCSP-IACs. Finally, analytical models were proposed for calculating the punching shear resistance of SCSP-IACs, and their accuracies were also verified with test data. • A novel steel–concrete–steel sandwich panel with interlocked angle connectors (SCSP-IACs) was proposed. • The influences of variant parameters on punching behaviors of SCSP-IACs were studied. • The punching shear failure criterion of the SCSSP-IACs under out-of-plane patch loads was revealed. • Analytical models were developed to predict the punching shear resistance of SCSP-IACs. [ABSTRACT FROM AUTHOR]

A series of 1,3,5-triphenylpyrazolines were designed and synthesized as photoinitiators (PIs) for photopolymerization processes. The P-N1-COPh molecule meets the characteristics of type II PI, and pyrazoline and benzophenone groups play important roles in photopolymerization. [Display omitted] • Four 1,3,5-triphenylpyrazolines were designed and synthesized as photoinitiators in photoinitiating systems. • The newly synthesized photoinitiators are highly sensitive to UV–vis LEDs (LED@365–425) • The pyrazoline-based photoinitiators with Iod or MDEA can initiate cationic polymerization as well as free radical photopolymerization. • New photoinitiators have good performances in application prospects of the photopolymerization. By introducing different substituents at the N1 position, a series of 1,3,5-triphenylpyrazolines were designed and synthesized as photoinitiators (PIs) for cationic and free radical photopolymerization processes. As evaluated through ultraviolet–visible (UV–vis) spectroscopy, fluorescence spectroscopy, theoretical calculations, electrochemistry, and electron spin resonance–spin trapping tests, all PIs show good photoinitiating properties under light-emitting diode (LED) irradiation at 365–425 nm. Their light absorption within the UV–vis range (λmax = 352–390 nm; ε max = 26 000–40 700 M−1 cm−1) is strongly influenced by the substituents on the N1 phenyl ring. Remarkably, the introduction of the carbonyl group redshifts the maximum absorption spectra from 375 nm to 390 nm, which could well match the emission of LEDs in the range of 365–425 nm. The pyrazolines, together with iodonium salt and N -methyldiethanolamine, can generate acid and free radicals under LED irradiation and conduct high-performance LED-induced cationic and free radical photopolymerization processes under 365–425 nm irradiation. Cationic polymerization is enhanced by the introduction of an electron-pushing group, and free radical polymerization is promoted by the introduction of a carbonyl group at the N1 position. These pyrazoline-based photoinitiating systems have promising applications in LED-induced photopolymerization. [ABSTRACT FROM AUTHOR]

New steel-concrete-steel sandwich beams with interlocked angle connectors (SCSSB-IACs) were first proposed, and their static behaviours were studied via conducting two-point loading tests. The failure mode, load–displacement response, resistance, and stiffness of the SCSSB-IACs were obtained. Moreover, the influences of thickness of steel faceplate, spacing of IACs, thickness of concrete core, shear-span ratio and interlocking bolts on static performances of the SCSSB-IACs were discussed. Two failure modes of the SCSSB-IACs were observed from the static tests, including flexural and shear failure. Moreover, test results indicated that the resistance and stiffness of the SCSSB-IACs were significantly affected by the thickness of steel faceplate, spacing of IACs and thickness of concrete core. In addition, the load–strain curves and deformation shapes of the SCSSB-IACs were obtained and discussed. Finally, analytical models were developed for predicting elastic stiffness and resistance of the SCSSB-IACs. The analytical models were also validated against the test data. • A steel-concrete-steel (SCS) sandwich beam with novel interlocked angle connectors (IACs) was proposed. • Two-point loading tests were conducted on the SCS sandwich beams with IACs (SCSSB-IACs). • The failure mode, load–displacement response, resistance, and stiffness of SCSSB-IACs were studied. • Analytical models were proposed to predict elastic stiffness and resistance of the SCSSB-IACs. [ABSTRACT FROM AUTHOR]

Two type novel aluminum foam filled energy absorption connectors were proposed to be inserted between the blast resistant façade and building to absorb blast energy and reduce blast load transferred to the building. In this paper, the nonlinear finite element (FE) method was adopted to study the energy absorption performances of the two type connectors. The FE models of the connectors under quasi-static compression loading were first established and the accuracies of the FE models were verified by comparing the force–displacement curves obtained from tests and FE analyses. Then, the FE models were used to investigate the effects of filled aluminum foam, plate thickness and geometry as well as aluminum foam width on the energy absorption performances of the two type connectors. It was found that the two type connectors showed comparable energy absorption performances and the specific energy absorption could be significantly improved by filling the connector with aluminum foam. [ABSTRACT FROM AUTHOR]

A novel energy absorption connector with pleated plate and aluminum foam as energy absorber was proposed to be inserted between the blast resistant façade and building to absorb blast energy and reduce blast load transferred to the building. The energy absorption performance of the connector under quasi-static compression loading was first studied by using experimental method. The deformation mechanisms were observed from the experiment and three different deformation processes were also identified. The effects of aluminum foam, pleated plate thickness and angle θ o (the angle between flat plate and pleated plate) as well as pleat number on the energy absorption performance of the connector were experimentally investigated, which showed that the energy absorption capacity could be improved by filling the connector with aluminum foam and increasing the pleated plate thickness, angle θ o and pleat number. Moreover, an analytical model for determining the load–displacement curve of the energy absorption connector was also developed and the predictions by the analytical model were proven to be reasonable by comparing with the experimental data. [ABSTRACT FROM AUTHOR]

A novel multilayer façade system, which consisted of a water steel tank integrated with a layer of energy absorbing aluminum foam panel and a stiffened steel panel, was developed to resist blast loading. The blast resistance and response behavior of the proposed façade system were investigated using nonlinear finite element method. The accuracy of the numerical model was verified by comparing the predicted results with the test results. The analyses showed that the energy absorbing aluminum foam layer was capable of reducing the blast load acting on the façade panel and building. The blast resistance of the multilayer façade system could be further enhanced by increasing the aluminum foam layer thickness. An analytical model considering Dynamic Increase Factor (DIF) and coupled deflection mode shapes was developed to predict the displacement response of the façade system subjected to blast loading. The accuracy of the analytical model was validated by comparing the predicted results with the numerical results. It was found that the analytical model with varying DIF could provide better prediction of the displacement response of the multilayer water façade system as compared to the method using a constant DIF. [ABSTRACT FROM AUTHOR]

The blast response behaviors of curved Steel-Concrete-Steel (SCS) sandwich shells were investigated using nonlinear finite element method. The accuracy of the numerical model was verified against the available field blast test results. The numerical results showed that shear connectors played a vital role in bonding the face plates and concrete core and therefore improving the blast resistant capacity of curved SCS sandwich shell. In addition, different failure modes for the curved SCS sandwich shell under close- and far-field blast loading were observed, i.e., separation of rear plate from concrete core and buckling of face plates for the shell under close- and far-field blast loading, respectively. The effects of rise height (or rise to span ratio) and rear to front plate thickness ratio on the blast responses of curved SCS sandwich shells were also studied. Numerical results showed that the damage of curved SCS sandwich shell could be reduced by increasing rise height and rear to front plate thickness ratio. Moreover, the energy absorption efficiency of concrete core also showed increase with increasing rear to front plate thickness ratio. [ABSTRACT FROM AUTHOR]

A novel multi-functional water façade system with the combined function of energy saving and blast resisting is presented in this paper. The façade system utilizes water confined in a thin tank to harness the solar thermal energy and to shield the building from solar radiation. It is particularly suitable for hot climate regions near the Equator due to the constant high dense solar radiation throughout the year. The energy saving performance of the water façade in terms of harnessing the solar thermal energy and reducing space cooling load was evaluated by conducting temperature monitoring tests. As for its potential as a protective layer against blast loading, the water façade was tested under simulated blast loading through dropping projectile on an inflated high pressure airbag. The addition of water was shown to reduce the displacement of water façade and improve the blast resistant capacity through comparing the maximum displacements of the water façades with and without infilled water. An analytical model incorporating varying dynamic increase factor and coupled deflection mode shapes was developed to predict the displacement response of water façade under blast loading and the analytical predictions on maximum displacement were conservative as compared to those from finite element analyses. [ABSTRACT FROM AUTHOR]

The dynamic responses of steel–concrete–steel (SCS) sandwich beams with novel interlocked angle connectors (IACs) under low-velocity impact were studied and presented in this paper. The impact tests on the SCS sandwich beams were first implemented using a drop-weight impact test machine, and the failure modes, displacement, and impact responses were obtained from the tests. The varying parameters considered in the tests included the thicknesses of the concrete and steel faceplates, as well as the spacing and type of IACs. The test results indicated that nine specimens experienced flexural failure, and one specimen exhibited shear failure. Moreover, local buckling of the top steel faceplate occurred in four specimens with a relatively larger spacing of IACs. A two-degree-of-freedom (TDOF) analytical model considering the strain rate effect was proposed for the SCS sandwich beam to obtain their impact forces and mid-span displacements. The analytically-predicted responses of the SCS sandwich beam with IACs agreed well with the test data. • A novel interlocked angle connector (IAC) was developed for the steel–concrete–steel (SCS) sandwich beam. • Drop-weight impact tests on the SCS sandwich beams with IACs were performed. • Flexural and shear failure modes were observed for the SCS sandwich beams under impact load. • An analytical model was developed for obtaining dynamic responses of the SCS sandwich beam under impact load. [ABSTRACT FROM AUTHOR]

[Display omitted] • The manuscript has five highlights as following below: • A novel PGS was fabricated by a cutting-reorganizing method. • The IP reaction of AGQDs and TMC could only grow in the 2D interface. • PGS showed a willow-leaf-like shape with a typical 2D porous structure. • The membrane were prepared by in-situ sealing technology with PA for the first time. • The PGS/PA composite membrane successfully overcame the "trade-off" effect. In this study, we proposed a novel interfacial polymerization (IP) method for porous graphene-based sheets (PGS) with 2D structure by recombining of amino graphene quantum dots (AGQDs) at the two phases interface, and then a large-area ultrathin composite films with excellent permeability and high selectivity were prepared by in-situ sealing technology with polyamide (PA) for the first time. Adjusting the pH of AGQDs solution could promote and regulate the formation of PGS with a lamella diameter of 2 μm, an ultrathin thickness of 3.2 nm and pore size of 2.71 nm, which showed a willow-leaf-like shape with a typical 2D porous structure. Then, the PGS at the interface was sealed in-situ by PA layer generated by injecting piperazine (PIP) in the IP process to form PGS/PA composite membrane. When the PGS synthesis time and PIP concentration were reached to 60 s and 0.02 w/v% respectively, the prepared PGS/PA composite membrane exhibited the best comprehensive properties, with an ultrathin thickness of 18.6 nm, super hydrophilic surface, excellent stability and strong alkali resistance. At this condition, the permeation flux of PGS/PA composite membrane could reach 28.4 L·m−2·h−1·bar−1, which was over 300% of the original PA composite membrane (9.1 L·m−2·h−1·bar−1), while the rejection of Congo red was maintained more than 99.4%, which successfully overcame the "trade-off" effect. [ABSTRACT FROM AUTHOR]

The response behavior of steel–concrete–steel (SCS) sandwich panels without shear connectors was experimentally studied under lateral pressure loading in this paper. The loading was applied by a hydraulic actuator on an inflated airbag to assert lateral pressure on the SCS panels. The failure modes and maximum resistance of the SCS panels were obtained from the test and compared with the numerical analysis results. It was found from the experimental and numerical studies that the end plates could function as shear connectors to achieve the composite action between face plates and concrete core. Based on the experimental and numerical observations, the formulae to predict the bending resistance and transverse shear resistance of SCS panel without shear connectors were developed and the accuracy of the proposed formulae was verified by comparing with the experimental and numerical results. [ABSTRACT FROM AUTHOR]

Lleras and Enns (2004) argued that the negative compatibility effect (NCE) may partly originate from object updating (OU) between a prime and mask. This process could occur not only at the feature level, which facilitates target identification via feature updating (the updated feature is identical to the target in the feature), but also at the response level, which benefits target response via response link updating (an updated response link has an identical reaction to the target). This study aims to present experimental evidence for the latter hypothesis that response link updating is one process that triggers an NCE. The design used a 4 (stimuli) to 2 (responses) paradigm in which the left-hand response was assigned to “1” and “2” and the right-hand response was assigned to “3” and “4” (counterbalanced across the participants). Additionally, we manipulated the strength of OU (strong, “1” and “3” as primes versus weak OU condition, “2” and “4” as primes), response set of prime and target (e.g., same, “1” and “3” as both primes and targets versus different response set, “1” and “3” as primes or targets but “2” and “4” as targets or primes), and compatibility (compatible versus incompatible). The results showed a significant NCE in the strong OU (effective object updating) and different response set (separating response link updating from OU process) condition. Combined with the response time quartiles, which showed a special developmental course for this condition, the results suggest that response link updating is one process that triggers an NCE when the prime and target come from different response sets, and the processing of response link updating does not share identical developmental courses as the motor inhibition. [ABSTRACT FROM AUTHOR]

The water storage tank was proposed as a multi-functional facade system characterizing energy saving and blast resisting. The energy saving performance, not presented in this paper, has been evaluated by experimental and numerical methods. The aim of this study is to propose simplified methods to reasonably predict the response of water storage tank under blast loading. Based on the equivalent single-degree-of-freedom (SDOF) method, the shock spectrum and dimensionless pressure–impulse (P–I) diagram were established, which can be used to evaluate the damage levels of water storage tanks subject to blast loading. The equivalent SDOF method cannot capture the varying deflection shape of structure during motion, herein the Lagrange equation method that allows for multiple deflection shape functions was proposed to predict the structural response. It was shown that the Lagrange equation method was better than the SDOF method since it could provide conservative predictions in all response regimes. Furthermore, the varying dynamic increase factor (DIF) with strain rate was incorporated into the Lagrange equation method to capture the strain rate effects. [ABSTRACT FROM AUTHOR]

The blast performance of water tank with an innovative energy absorbing support was studied to reduce the support reaction force and mitigate the damage on the water tank. The aluminum foam was adopted as the energy absorbing material, since it has high energy absorbing potential during crush plateau and safety backup zone after the compaction strain. Finite element model considering fluid and structural interaction in which the water is modeled using the Eulerian formulation and the steel tank by Lagrangian formulation is proposed. The proposed numerical model of water tank was verified by comparing the predicted results with the test results obtained from dynamic pressure tests on steel tanks filled with water. The numerical results showed that the support reaction force depends on the density and yield strength of the aluminum foams and the reaction force could be reduced significantly if softer aluminum foam was chosen. The total displacement of the water tank was increased by up to 38% due to the increase in deformation of the energy absorbing foam. The aluminum foam was proposed to absorb the blast energy and reduce the damage on the water tank. However, more damage on the water tank was observed when a very low density aluminum foam support was used. This was attributed to the increased external work done by blast loading which was higher than the energy absorbed by the aluminum foam support. [ABSTRACT FROM AUTHOR]

A flat nanocomposite plate was fabricated by using the surface-modified Fe nanoparticles (NPs) as the microwave absorbent, carbon fibers (CFs) as the reinforced phase and epoxy resin (ER) as the matrix. Fe NPs were synthesised by an arc discharge plasma method and subsequently modified by silane coupling agent (KH-550) to improve its dispersion in the organic matrix of ER. To measure the realistic microwave absorption properties of such a flat nanocomposite plate, a series of square plates (20 × 20 cm 2 ) was made from recombining the modified Fe NPs (20 wt.%, 30 wt.% and 40 wt.%) into the ER matrix with/without orientated CFs inside. It was observed that the orientation of CFs plays an important role in the microwave absorption, in particular through a strong reflection of microwave inwardly as the CFs’ array is vertical to the direction of incident microwave. The inner strong reflection of microwave by CFs can bring great probabilities to further consume it by Fe NPs absorbent and result in improved microwave absorption performance of the nanocomposite plate. It is indicated that the plate containing 30 wt.% of Fe NPs with a perpendicular manner between the directions of CFs array and incident microwave exhibits higher reflection loss (RL) of −16.2 dB at 6.1 GHz frequency, and this plate has 77.78 MPa flexural strength at 3.74% deformation. Excellent RL property is ascribed to an optimum structure of nanocomposite plate with favorable multi-reflection of microwave inside, structural resonance, appropriate conductivity, impedance match, interface polarization. [ABSTRACT FROM AUTHOR]

The structural performance of water tank under static and dynamic pressure loading was experimentally investigated in this paper. The loading was applied using hydraulic actuator/dropped projectile on an inflated high pressure airbag to assert static/dynamic pressure on the specimens. The failure modes and maximum resistance of the specimens were obtained from the test and compared to the numerical results. It was found from the static pressure test that the water tank filled with water exhibited up to 31% increase in flexural resistance under static loading as compared to the empty water tank with the same material and geometry. The improvement was attributed to the effects of water in maintaining the section modulus and delaying the local buckling of the tank. Water was also found to be useful in reducing the deformation of the tank under dynamic pressure loading. Nonlinear finite element analysis was conducted to investigate the behavior of water tank subject to static and dynamic pressure loading and the accuracy of the numerical models was verified by comparing the predicted displacement responses with those observed from the tests. [ABSTRACT FROM AUTHOR]

The performance of non-composite Steel–Concrete–Steel (SCS) sandwich panels under impact-induced impulsive loading was experimentally and numerically studied in this paper. Two SCS sandwich panels with different core depths were tested and the impulsive loading was applied in the laboratory by utilizing an inflated high pressure airbag to transfer the impact load from dropped projectile onto the panels. The deformation modes, applied pressures, displacement and strain responses of the panels were determined in the test. A combination of bending and shear deformation mode was observed in the SCS panel with thinner core while there was minimal visible deformation in the thicker panel. The maximum and permanent deformations of the panel with thicker panel were significantly reduced due to the increase in resistance and mass. Debonding between grout core and bottom plate was also noted in both panels during impact from the strain–time histories. Following the test, Finite Element (FE) models were constructed and verified against the test data to simulate the tests. It was shown in the FE analysis that the steel plates absorbed more energy due to its higher strength and ductility as compared to the grout core under the impact-induced impulsive pressure loading. [ABSTRACT FROM AUTHOR]

A novel series of N -(4-aryl-5-aryloxy-thiazol-2-yl)-amides as RORγt inverse agonists was discovered. Binding mode analysis of a RORγt partial agonist ( 2c ) revealed by co-crystal structure in RORγt LBD suggests that the inverse agonists do not directly interfere with the interaction between H12 and the RORγt LBD. Detailed SAR exploration led to identification of potent RORγt inverse agonists such as 3m with a pIC 50 of 8.0. Selected compounds in the series showed reasonable activity in Th17 cell differentiation assay as well as low intrinsic clearance in mouse liver microsomes. [ABSTRACT FROM AUTHOR]

• A novel interlocked angle connector (IAC) was proposed for steel-concrete-steel sandwich structures. • The tensile performances of IACs were experimentally investigated. • Analytical models were developed to predict tensile resistances of IACs. • The geometric superiority of IACs was demonstrated. The mechanical performances of steel-concrete-steel (SCS) sandwich structures were generally governed by the interfacial bonding between steel and concrete provided by shear connectors. This paper aims to propose a new interlocked angle connector (IAC) for sandwich structures to enhance the steel-concrete interfacial bonding performances, and its tensile behaviors were also experimentally and analytically studied in detail. There were 14 specimens with different parameters being designed and tested, and the different confinement effects of concrete around IACs were also considered in this study. The experiments revealed three failure modes of IACs embedded in concrete, i.e., concrete breakout failure, tensile fracture failure of the steel angle and concrete direct shear failure. The evident influences of confinement effect of concrete on the failure modes and tensile resistances of IACs were also observed. In addition, the tensile resistance of IACs was found to be significantly improved with the increasing of embedded depth of IACs and thicknesses of steel sheet. Analytical models were proposed for predicting the tensile resistances of IACs, and the predicted values showed a good match with the test results. Moreover, the tensile resistances of IACs were compared with those of existing semi-direct-link connectors, and the proposed IACs provided 55.9% higher tensile resistances than the existing semi-direct-link connectors. Thus, the steel-concrete interfacial bonding performances of SCS structures with IACs would be significantly enhanced. In subsequent studies, the mechanical performances of IACs under the combined actions of tension and shear should be concerned. [ABSTRACT FROM AUTHOR]

The numerical method was adopted in this paper to study the performance of water tank under blast loading. The established numerical model was verified by comparing with the test results and then utilized to study the effects of water on the response of water tank under blast loading. The numerical results showed that water can significantly reduce the response of water tank under blast loading through reducing the external work. As for the boundary reaction force, although the maximum boundary reaction force was increased by filling in water, the increase in maximum boundary reaction force was less significant as compared to the decrease in response. Besides, the positive duration of boundary reaction force was reduced by filling in water. The simply supported and axially restrained boundary conditions were compared to study their effects on the response of water tank. It was found that the blast resistant performance of axially restrained water tank could be significantly improved as compared to the simply supported water tank. This can be attributed to the increased internal energy and reduced external work by adopting the axially restrained boundary condition. [ABSTRACT FROM AUTHOR]

The current study focused on contributions to the negative compatibility effect (NCE) from object-updating at the perceptual level and self-inhibition (i.e., automatic motor inhibition) at the response (motor) level. We hypothesized that contributions to the NCE from these two levels were moderated by the strength of stimulus and reaction (S–R) link: object-updating should have greater impact on the NCE with weak S–R links, but both object-updating and self-inhibition should impact on the NCE when the S–R links became strong. To test this hypothesis, in two experiments we used a novel type of stimuli and manipulated mask relevance (relevant versus irrelevant mask) and prime/target compatibility. Participants performed two tasks over three successive days. Results showed that under equivalent masking effectiveness between the two conditions of mask, a significant NCE was observed only in the relevant mask condition when the S–R links were weak, but both close to equal NCE sizes were observed in the two mask conditions when the S–R links were acquired through practice. The results indicated that perceptual and motor contributions to the NCE were moderated by the strength of S–R links, if the strength of the links was too weak to trigger the following inhibition, the NCE primarily originated from object-updating at the perceptual level; if the strength of the links was reinforced by practice, which exceeded the inhibitory threshold, the NCE originated from both object-updating and self-inhibition, but the latter was primarily responsible. [ABSTRACT FROM AUTHOR]

Motion parameters measurement is essential for understanding animal behavior, exploring the laws of object motion, and studying control methods. Nowadays, advanced computer vision based on machine learning technology supports markerless object tracking in 2D videos. However, due to the fact that all objects move in three-dimensional space, this paper introduces a method of measuring motion parameters using 3D pose estimation. First, an enhanced iterative bundle adjustment algorithm is proposed for multi-camera calibration in a multi-camera vision system by adding two control parameters, which dramatically reduces the reprojection error of multi-camera calibration and lays the foundation for high-precision triangulation. Then, a new spatiotemporal loss function is proposed, which considers the relationship between key points that do not constitute limbs, thereby improving triangulation accuracy. The new multi-camera calibration algorithm is evaluated on ChArUco and 3D pose estimation for metronome, planet pendulum, human hand, Koi, and cheetah. The experimental results show that: (1) the two hyper-parameters in the enhanced iterative bundle adjustment algorithm effectively suppress the influence of noise and play a good role in reducing the reprojection error of multi-camera calibration; (2) the spatiotemporal loss function has a strong constraining ability, the time loss can stabilize high frame rate video triangulation to maintain accuracy, while the space loss can improve the accuracy of triangulation for more complex structures; (3) multi-view data fusion is also conducive to improving the accuracy of triangulation. Moreover, the method was successfully applied to some actual measurement scenes: (1) the accurate measurement of the frequency of a metronome; and (2) the success measurement of the movement of a Koi, which conforms to the basic model of fish swimming. Some dynamic measurement results are displayed at https://github.com/wux024/AdamPose. [ABSTRACT FROM AUTHOR]