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This paper investigates the seismic behavior of a seismic-damaged double-deck viaduct frame pier (DVFP) strengthened with CFRP and enveloped steel, four strengthened DVFP specimens with different degrees of initial damage were tested under quasi-static cyclic loading. Based on the test results, the hysteretic behavior, the stiffness and strength degradation, crack propagation, and failure mechanism were firstly analyzed. Then, the damage indexes of the tested specimens were calculated with different models to evaluate the seismic strengthening performance. Results of this study show that CFRP and enveloped steel strengthening could effectively improve the strength and ductility of pre-damaged DVFPs. The ultimate load, the failure displacement and the displacement ductility of the moderately damaged specimen after being strengthened were found to increase by 120.74%, 35% and 32.33%, respectively. For the severely damaged specimens with CFRP and enveloped steel strengthening, the figures were 105.36%, 25.98% and 31.41%, respectively. The research results can provide reference for the hybrid strengthening application of seismic-damaged DVFP. [ABSTRACT FROM AUTHOR]

In this study, Bi2Ti2O7−TiO2 was synthesized in a single step via the sol–gel method, after which its photocatalytic properties and mechanisms were investigated. Moreover, our study proposed and evaluated the use of salicylic acid (SA) and basic magenta (BM) as model contaminants in quenching experiments. When SA was used as the model pollutant, the reaction rates showed negative values. Therefore, the experimental results failed to truly and effectively reflect the actual photocatalytic performance of Bi2Ti2O7−TiO2. However, when BM was used as the model pollutant, the reaction rates were all positive and the experimental results were far more descriptive. Hydroxyl radicals (·OH), superoxide radicals (·O2−), and photogenerated holes (h+) all contribute to the photocatalytic activity of Bi2Ti2O7-TiO2, with ·OH making the largest contribution. Collectively, our findings can serve as a basis to improve the accuracy and efficiency of future photocatalytic mechanism experiments, which could bring great economic benefits. [ABSTRACT FROM AUTHOR]

This paper presents a miniaturized ultra-wideband (UWB) antipodal Vivaldi antenna (AVA) array with low-scattering characteristics integrated a hybrid diffusive-absorptive metasurface. Periodic elliptical slots at the outer edges and a dielectric lens are utilized for antenna element to improve performances including miniaturized size, wide bandwidth, and high gain. The optimized element is fabricated and measured, the results demonstrate that the − 10 dB impedance bandwidth is 4.5–50 GHz with a ratio bandwidth (fH/fL) of 11.1:1, and the maximum gain at 35 GHz is 12.7 dBi, which are in good agreement with simulation. By loading an optimized Minkowski-shaped metasurface as the ground reflector, which combines the multielement phase cancellation (MEPC) and EM absorption technology, the 4 × 4 array realizes a low radar cross section (RCS) without the radiation performance degradation. Simulated and measured results show that the proposed low-scattering array has a 10-dB RCS reduction band ranging from 5 to 50 GHz at normal incidence for both polarizations. Furthermore, the array structure shows extremely low-observable capability, which is larger than 15 dB of the RCS reduction from 7.1 to 50 GHz with a ratio bandwidth of 7.0:1. The results verify the feasibility of improving the performance of antenna and the UWB low-scattering functionality. [ABSTRACT FROM AUTHOR]

Four composite steel–concrete frame columns were constructed to investigate the seismic performance of seismic-damaged composite steel–concrete frame columns strengthened with carbon fiber reinforced polymer. The test consisted of pre-damage loading, rehabilitation with carbon fiber reinforced polymer and destruction tests under lateral cyclic loading. The effectiveness of strengthening seismic-damaged columns with carbon fiber reinforced polymer and the strengthening effect on different degrees of seismic damage were studied. Also, based on the test data, various parameters were obtained, including the hysteretic loops, skeleton curves, axial compression ratio, number of pasted layers of carbon fiber reinforced polymer, ductility, dissipative ability, ultimate strength, stiffness degradation, etc. The results revealed that the failure mode of all the columns was bending failure. The study indicates that the rehabilitated columns can reach or even exceed the level of their original seismic performance before seismic damage up to a certain extent of damage level. Composite steel–concrete frame columns strengthened with carbon fiber reinforced polymer sheets were simulated using the finite element analysis software ABAQUS. The comparison of the results of the conducted analytical study with the experimental results revealed that they are basically consistent with each other. [ABSTRACT FROM AUTHOR]

Gonggan' (Citrus reticulata) is a famous, high-quality and special citrus cultivar in the Xijiang River valley, Guangdong Province. However, it easily suffers from postharvest diseases, and thus is not tolerant to storage. Based on the preliminary test results, prochloraz-manganese chloride complex was selected as the disinfectant, and prepared into different concentrations for carrying out preservation test by dipping fruits. The fruit weight loss, soluble solids content and decay rate were analyzed, and the application security and sensory evaluation for fruit freshness and flavor were observed. The results showed that dipping fruits with prochloraz-manganese chloride complex solution had significant preservation effect on 'Gonggan' fruits in postharvest storage; the suitable concentration was 2.0 - 3.0 g / L, and the decay rates of fruits stored at room temperature for 30, 60 and 90 d were below 5%, 10% and 15%, respectively. Plate inoculation test further revealed that the pathogen of 'Gonggan' was sensitive to prochloraz-manganese chloride complex, and the concentration of 1.0 g/L was enough to produce significant antimicrobial effect. Other technical links related to postharvest preservation of 'Gonggan' with prochloraz-manganese chloride complex were discussed. [ABSTRACT FROM AUTHOR]

[Objective] The paper was to solve the weakness of heavy postharvest diseases and non-endurable storage of 'Shatangju' , to improve the preservation effect of 'Shatangju'. [Method] Fruits were dipped in different concentrations of prochloraz-manganese chloride complex solutions. The postharvest weight loss rate, soluble solids content and decay rate of fruits wrere determined, and the safety of chemical agents was observed and evaluated. [Result] Prochloraz-manganese chloride complex had significant preservation effect on postharvest 'Shatangju' fruits, and the appropriate concentration was 0. 15%-0.20% (effective content) ; the decay rates of fruits stored at room temperature for 15 , 30 , 45 , 60 and 90 d wereO, 5% , < 10% , < 10% and <30% ; there was no specific changes in smell and flavor of non-decayed fruits. [Conclusion] Prochloraz-manganese chloride complex solution had significant preservation effect on ' Shatangju ' by inhibiting and reducing the growth and development of pathogenic bacteria, and the effect was much belter under refrigeration condition. [ABSTRACT FROM AUTHOR]

Lou-temperature stress is a major abiotic stress influencing plant growth, economic yield and quality worldwide. Precise and reliable identification and test of plant cold resistance is a foundation for exploring low-temperature damages, cold resistance mechanism of plants, cultivating and innovating quality cold-resistant germplasm resources, which is rather important for woody plants because their perennial and large-sized characteristics. Generally, most researches on plant cold-resistant physiology focused on identification and utilization of cold resistance worldwide, and a few on test methods of cold resistance, but cold resistance mechanism has been less reported. Therefore, researches on methods of identifying and testing plant resistance have achieved considerable progress, accumulated much experience and formed characteristics gradually in terms of methodology. Current methods of identifying plant cold resistance include open field/outdoor cultivation evaluation, cold and frost damage investigation, simulated cold weather, and mathematical model forecast. And the methods of testing plant cold resistance include growth condition test, frozen index investigation, electrolyte leakage, bioelectrical impedance mapping and so on. Synthesizing the methods of identifying and testing plant cold resistance should be a key matter in the present and future researches and application of plant cold resistance physiology, improvement and innovation of the identification and test will be an important direction of the future researches. Identification and test of plant cold resistance based on genomics, meta-bonomics and proteomics should be the new trend of the researches on physiology and ecology of plant cold resistance. [ABSTRACT FROM AUTHOR]

The state of zero effective stress is a situation at which the effective stress of saturated sand decreases to zero in the process of liquefaction. In the state of zero effective stress, sand particles suspend in water and the foundation is vulnerable to much large lateral deformation. The state of zero effective stress can be achieved through dynamic loading tests, but the obtained state is difficult to sustain a steady situation. To simulate the suspended sand in water under fully liquefied condition, plastic sand, characterized by small specific gravity, is used instead of quartz sand to build an inclined foundation. Salt water with similar density is used to pass in slowly near bottom of the foundation. As observed in tests, the plastic sand is able to suspend in sodium chloride solution (salt water) of a specific density and thus this model can be used to simulate the lateral spreading of a foundation under zero effective stress state. Lateral deformation occurs within a certain depth beneath the ground and the magnitude increases from the bottom up, showing nonlinear behaviors. This paper presents a physical modeling approach for achieving the state of zero effective stress under static laboratory condition. [ABSTRACT FROM AUTHOR]

In order to study the seismic behavior of CFRP-reinforced seismic-damaged joints in composite frame consisting of concrete-filled square steel tubular (CFSST) columns and steel beams, four one half scaled models of exterior joints in composite frame consisting of CFSST columns and steel beams were designed and manufactured. The test consisted of pre-damage loading, rehabilitation with CFRP and destruction tests under lateral cyclic loading. The effectiveness of CFRP-strengthened seismic-damaged joints and the reinforcement effect on different levels of seismic damage were studied. Based on the test data, the hysteretic loops, skeleton curves, the CFRP strain, ductility, dissipative ability, ultimate strength and stiffness degradation, etc. were obtained. Results show that CFRP-strengthened seismic-damaged exterior joints in composite frame consisting of CFSST columns and steel beams meets the strong column-weak beam requirement of seismic design, and the failure modes of all joints are bending failure of beam. The reinforcement with CFRP has a significant on increasing the ultimate capacity and the seismic behaviors of the joints. The study indicates the rehabilitated joints can reach or even exceed the level of their original seismic performances before seismic damage in a certain extent of damage level. [ABSTRACT FROM AUTHOR]

Propagation and cultivation results showed that grafting southern highbush blueberry cultivar ʽSharpblueʼ taking Wufanshu ( Vaccinium bracteatum Thunb.) as rootstock has much high survival rate, and inlaid bud-grafting and one-bud cut-grafting were both suitable for application. The grafted blueberry saplings integrated the excellent biological traits of rootstock species and scion cultivar, growth vigor was markedly stronger than that of the same-aged none-grafted blueberry in field planting. Further more, early bearing and productivity and fruit quality of grafted blueberry were also significantly improved. Grafting is a practical and efficient technology innovation in blueberry production. [ABSTRACT FROM AUTHOR]

• Influence of damage degrees and confinement materials on seismic behavior of joints. • FE models of strengthened joints are calibrated with test results. • The predicted models of the shear capacity are good agreement with test results. • The results provide useful information for the engineering application. The seismic behavior of reinforced concrete (RC) beam-steel-reinforced concrete (SRC) column composite joints strengthened with carbon fiber-reinforced polymer (CFRP) sheets and enveloped steel jackets (ESJ) was investigated. Based on the existing regulations, nine specimens were designed and built to simulate pre-damage loading, rehabilitation with CFRP sheets or ESJ, and destruction tests under lateral cyclic loading to determine the performance of the two reinforcement materials (CFRP sheets and ESJ) for different degrees of seismic damage. An analysis of the hysteretic curves, skeleton curves, ductility, energy dissipation, bearing capacity degradation, stiffness degradation, and strain-displacement curves of the specimens indicated that the two strengthening materials exhibited good reinforcement performance. The ESJ improved the bearing capacity and stiffness of the specimens and the CFRP sheets improved the ductility and energy dissipation of the specimens, thereby improving the seismic behavior of the specimens. The severely damaged specimen strengthened with the CFRP sheets or ESJ did not collapse in a simulated strong earthquake and was similar to or even exceeded the seismic performance of the original specimen; this result is important and applicable to engineering practice. The ductility and energy dissipation was lower for the ESJ-strengthened specimen than the CFRP-strengthened specimen. Therefore, the ESJ material is preferable when only one type of material is used for strengthening the specimen. The seismic performance of the RC beam-SRC column frame joints strengthened with the CFRP sheets and ESJ was simulated using the finite element analysis software ABAQUS. There was a good agreement between the simulation results and the experimental results. It was proved that the simulated and experimental results of the ultimate bearing capacity of the joints in the core zones were in good agreement, which meets the design principle of "strong joint, weak member". [ABSTRACT FROM AUTHOR]

Hybrid Fiber High Performance Concrete (HFHPC) utilizes the synergistic effects of macro and micro fibers at different stages, which can effectively improve its mechanical properties, fracture toughness, ductility, and impact resistance after high temperature. The bonding between steel bars and hybrid concrete is a fundamental prerequisite for ensuring that these two materials with completely different mechanical properties work together. In order to study on bond-slip performance and damage evolution mechanism of deformed reinforcing bar embedded in steel-polyvinyl-alcohol (S-PVA) hybrid fiber high performance concrete (HFHPC) after high temperature, a total of 75 specimens were designed and manufactured by selecting volume fraction of steel fiber and PVA fiber and dosing of slag powder as the orthogonal test factors, and the central pull-out test were completed after exposure to room temperature, 200℃, 400℃, 600℃, and 800℃. The experimental results indicate that the bonding failure mode of HFHPC specimens all showed steel bar pull-out failure after high temperature, and the bond stress-slip curve can be divided into 4 stages: elastic rise stage, nonlinear rise stage, plastic degradation stage, and residual stage. As the temperature increases, the bonding strength of HFHPC specimens gradually decreases and the peak slip gradually increases. The addition of hybrid fibers can significantly improve the bonding ductility and energy dissipation capacity of deformed reinforcing bar embedded in S-PVA HFHPC after high temperature. When the temperature is below 200℃, the bonding strength damage rate of S-PVA HFHPC specimens is relatively slow; when the temperature exceeds 200℃, the bonding strength damage rate of S-PVA HFHPC specimens increases. • The effects of steel-polyvinyl-alcohol hybrid fibers on bond-slip performance after high temperature were investigated. • Improvements in the bonding failure mode, bond strength, slip, energy consumption and ductility after high temperature were observed. • Damage evolution mechanism of deformed reinforcing bar embedded in steel polyvinyl-alcohol hybrid fiber high performance concrete after -high temperature were developed. [ABSTRACT FROM AUTHOR]

The combination of superelastic shape memory alloy fibers and ECC materials can form a new SMA fiber reinforced ECC composite material (SMAF-ECC) with good self-centering performance. In order to study the self-centering performance of the new composite material, 6 groups of pre-notch beam specimens were made for three-point bending cyclic loading tests, and the failure phenomenon, hysteresis curve, self-centering effect and influencing factors of the specimens were analyzed. The research results show that when the SMA fibers are effectively anchored in the ECC matrix, the SMA fibers can exert the superelastic properties to provide the ECC beams with recoverying force, and realize the crack self-closure and deflection self-recovery function for the beams, with the minimum residual crack width and deflection is only 0.9 mm and 1.3 mm respectively. Increasing fiber content can cause a small increase in the self-centering ability of the beams. However, only when the fiber diameter is appropriate, better self-centering effect can be achieved, but the difference caused by fiber diameter in the test was only 5%. SMA Fiber end forms have significant influence on self-centering performance. The knotted end beam can get a more than 70% self-centering ratio, while the straight end beams and bended end beams have no self-centering ability. The research results provide important reference for the research and application of this new self-centering materials and their structures. [ABSTRACT FROM AUTHOR]

To study the seismic behavior of unsymmetrical steel reinforced concrete column, cyclic loading tests were carried out on 12 columns with T-shaped section steel and 12 columns with L-shaped section steel. The test parameters included shear span ratio, axial compression ratio, stirrup ratio and presence of cross tie. Mechanical process, failure mode, hysteretic characteristics, skeleton curves, ductility and energy dissipation ability were taken into comparison. The result indicates that unsymmetrical steel reinforced concrete column possesses good seismic performance under constant axial compression and cyclic horizontal load. The failure modes include bonding failure, shear-bond failure, shear compression failure and shear-composition failure. Obvious asymmetry phenomenon of positive and negative hysteresis loop are shown. The span ratio has great influence on failure mode and shear-composition failure usually takes place in L-shaped steel section column. With the increase of axial compression ratio, the ductility decreases, which is obvious in L-shaped steel section column. The ductility and bearing capacity of the T-shaped steel section columns are improved greatly with the increase of stirrup ratio, but not obvious for T-shaped steel section column with smaller span ratio. Cross ties can improve bearing capacity, limit strength and stiffness degradation and enhance deformation capacity of L-shape steel section columns clearly. [ABSTRACT FROM AUTHOR]

The paper microzones method (PMZs) is a green chemical method that uses the principle of the three primary colors of red, green and blue (RGB) to detect the water quality of the droplets on white paper. However, this method is rarely used in the performance evaluation of photocatalysts. The paper details the first use of paper microzones utilized in the evaluation of photocatalyst performance. A sol-gel method was used to prepare molecularly imprinted modified TiO 2 photocatalysts for the treatment of different wastewaters, and characterized the catalysts using XRD and several other methods. The reliability of PMZs on the evaluation of photocatalytic activity and selectivity was also analyzed. The following results were obtained: EP-TiO 2 catalysts (EP, ethyl paraben, the imprinting molecule) with different S doping levels were synthesized using a one-step sol-gel method, and the best S doping ratio was found to be n(Ti):n(S) 3:1. S-EP-TiO 2 was found to be 100% anatase and showed excellent photocatalytic performance, while the PMZs method accurately determined changes in RGB levels for the photocatalytic degradation process of pollutants using S-EP-TiO 2 as the photocatalyst. A photocatalytic kinetic analysis showed the PMZs method was quite suitable for the evaluation of photocatalyst activity, but the evaluation of selectivity needs improvement. This method is a promising green chemistry way to evaluate photocatalyst performance and the rapid detection of outdoor sewage water quality. [Display omitted] • Innovative application of Paper microzones in the evaluation of photocatalytic performance. • Paper microzones method is compared with the traditional spectroscopic method. • Simple operation and green chemistry for environmental research. [ABSTRACT FROM AUTHOR]

• The mechanical property tests and test of GFRP reinforced hybrid fibre concrete short columns subjected to eccentric compression were conducted. • The cooperative effect of the GFRP reinforcement and the steel-PVA hybrid fibre concrete with different fibre ratios under eccentric loading was explored. • The addition of fibres can effectively prevent the crack generation and development and improve the bonding property between reinforcement bars and concrete. • The equation for the calculation of the ultimate compressive capacity of partial sections of eccentric columns is proposed. This paper presents the results of an experimental study carried out on the GFRP reinforced hybrid fibre concrete short columns subjected to eccentric compression. In this study, hybrid fiber-reinforced concrete was prepared in different volume ratios of hybrid fibers and the cooperative effect of the GFRP reinforcement and the steel-PVA hybrid fibre concrete with different fibre ratios under eccentric loading was explored. 10 GFRP reinforced hybrid fibre concrete short columns and 2 plain reinforced concrete short columns were tested to investigated their eccentric compressive properties. The tests results are presented in terms of failure modes, longitudinal reinforcement strain, concrete compressive strain and compressive load capacity of GFRP reinforced hybrid fibre concrete eccentrically compressed short columns. The results show that the concrete on the compressed side was crushed when the specimen under both the initial eccentricity of 50 mm and 100 mm the reinforcement were pulled on the tension side of specimen under a larger initial eccentricity of 100 mm. The addition of fibres can effectively prevent the crack generation and development and improve the bonding property between reinforcement and concrete. Besides, the addition of steel fibre contributes a better performance on the ultimate compressive capacity of specimen under a lager initial eccentricity with an optimal ratio of steel fibre at 1.4 %. PVA fibre effectively improve the ductility of the concrete, so that the hybrid fibre concrete elements remain relatively its integrity after failure. Finally, considering the effect of GFRP reinforcement and different ratios of steel fibre and PVA fibre on the compressive capacity of short concrete columns, the equation for the calculation of the ultimate compressive capacity of partial sections of eccentric columns is proposed, and a good agreement was observed between the tested and calculated value. [ABSTRACT FROM AUTHOR]

This paper reports a study of the effects of different concealed bracing materials on the seismic performance of short-legged shear walls and presents the results of low-frequency cyclic loading tests on three L-shaped short-leg shear walls—one wall without concealed bracing and the other two with concealed bracing materials of steel bars and SMA bars, respectively. The tests were aimed mainly at analyzing the effects of different concealed bracing materials on seismic performance indicators such as crack pattern, bearing capacity, ductility, hysteresis performance, stiffness, and energy dissipation of the L-shaped short-leg shear walls. The results revealed that their seismic performance with concealed bracing was better than without concealed bracing. The short-leg shear walls with SMA bar concealed bracing had the lowest number of cracks and the smallest crack width, and the effect of delaying the development of cracks was more evident. The short-leg shear walls with steel reinforcement and SMA-bar concealed bracing were better in bearing capacity, ductility, and energy dissipation capacity, with, respectively, 11% and 26.3% increase in ultimate load, 4% and 18.6% increase in ultimate displacement, and 12% and 28% increase in energy dissipation. It can be seen that setting concealed bracing effectively enhances the seismic performance of short-leg shear walls, and that short-leg shear walls with concealed SMA bar bracing have the most significant improvement in seismic performance. • The low-frequency cyclic loading tests on three L-shaped short-leg shear walls with different concealed bracing materials were conducted. • The effects of different concealed bracing materials on seismic performance indicators of the L-shaped short-leg shear walls were explored. • The short-leg shear walls with concealed SMA bar bracing have the most significant improvement in seismic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrochemical properties were explored using smartphone photos. • The paper microzones method is accurate for high dye concentrations. • Using the paper microzones and smartphone to make experiments more green chemistry. • The spectrophotometric method is more adaptable than the paper microzones method. Methods of electrochemical correlation are becoming more complex and costly with the lack of a simple electrolytic analysis method. Herein, an interesting analysis of the performance of electrocatalytic degradation of different dyes was carried out using a modified paper microzones method (PMZs) performed with a smartphone, and data from spectrophotometers were used for comparative analysis. At the same voltage and in the same reaction cell, the same mass of sodium sulphate, acetic acid and pure water were added according to the strength of the electrolyte to degrade methyl orange(MO), fuchsin basic(FB), methylene blue(MB) and the mixture of these dyestuffs. When measured by the PMZs method, the correlation coefficients were above 0.9 in the concentration range of 5–50 mg/L, the range of variation of LOD values was 3.843–9.561 mg/L and the range of variation of LOQ was 11.646–28.973 mg/L. When measured by the spectrophotometric method, some of the dyes only had a greater correlation in the range of 5–40 mg/L. The range of variation of LOD values was 0.900–9.213 and the range of variation of LOQ was 2.727–27.917 mg/L. When FB was used as a degradation object, the decrease in absorbance at 80 min was 21.83%, 35.93%, 60.90% and the increase in grey value was 0.40%, 3.04%, 3.25% under the conditions of electrolytes only water, CH 3 COOH, Na 2 SO 4 , respectively, and maintained P less than 0.05 at different moments. Hence, the related results contribute to the further application and development of green chemistry PMZs in electrochemical analysis and environmental science. [ABSTRACT FROM AUTHOR]

Concrete-filled steel tubular columns have been studied extensively worldwide. Such columns provide stable energy dissipation, which is ideal for earthquake engineering application. However, most applications use rectangular steel tubular sections. In the location of wall intersections, these sections often create sharp corners, which are architecturally displeasing. In some facilities such as schools and correctional facilities, sharp corners are even prohibited due to their potential hazard to occupants. To resolve the issue, concrete-filled crisscross steel tubular columns (CCSTCs) have been proposed. Three half-scaled specimens were constructed and tested under cyclic displacement loading history. The experimental results were used to calibrate numerical models of the components and further used to examine the seismic behavior of a three-story prototype office building located in Los Angeles. The results showed the proposed CCSTC has excellent energy dissipation and postearthquake performance, and hence it can be used as an alternative lateral force resisting system for seismic applications. [ABSTRACT FROM AUTHOR]

Little is known about the bioaccumulation and trophic transfer of total mercury (THg) and methylmercury (MeHg) via food webs in terrestrial ecosystems, especially in subtropical forest ecosystems. In the present study, THg and MeHg were determined as well as the carbon (δ13C) and nitrogen (δ15N) isotope composition in samples of soils, plants, invertebrates, and songbird feathers to construct food webs in a remote subtropical montane forest in Mt. Ailao, southwest China and assess the bioaccumulation, biomagnification, and trophic transfer of Hg. Results showed that the trophic levels (TLs) of all consumers ranged from 0.8 to 3.3 and followed the order of songbirds > spiders > omnivorous insects > herbivorous insects > plants, and THg and MeHg exhibited a clear biomagnification up the food chain from plants-herbivorous/omnivorous insects-spiders-songbirds. The lowest MeHg concentration was observed in pine needles ranged from 0.104 to 0.949 ng g−1 with only a 1.6% ratio of MeHg to THg (MeHg%), while the highest MeHg concentrations ranged from 425 to 5272 ng g−1 in songbirds with MeHg% values of up to 96%. High values of trophic magnification slope (TMS) for THg (0.22) and MeHg (0.38) were observed in plant-invertebrate-songbird food chain, verifying the significant bioaccumulation of Hg, particularly MeHg, in the remote subtropical forest ecosystem. This study confirmed the production and efficient biomagnification of MeHg in remote subtropical montane forest and the significant bioaccumulation of MeHg in terrestrial top predators. [Display omitted] • THg and MeHg increased with trophic positions in forest food webs. • THg exceeded adverse effect thresholds in insectivorous songbirds. • MeHg significantly biomagnified in subtropical forest food webs. Significant biomagnification of methylmercury exists in a remote subtropical forest food web. [ABSTRACT FROM AUTHOR]