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With global warming intensifying, weather patterns become more volatile and extremes more common. Tornadoes are the most destructive natural disasters causing significant damage to infrastructure. Meanwhile, high-speed railways now face greater risks from tornado events as the national railway network and mass transit trains expand. Thus, studying the tornado flow characteristics and associated effects on high-speed trains is necessary. A study is presented regarding the wind-loading characteristics of a high-speed train running over a railway bridge induced by a tornado belonging to the future railway network. The wind-loading characteristics analyses are performed using the improved delayed detached eddy simulation method. After verifying the numerical approach and mesh strategy, computational studies are conducted to produce a tornado-like vortex and investigate the tornado-induced wind-loading characteristics of a high-speed train running on the bridge by combining a tornado simulation with a moving mesh technique. For the wind-loading parameters studied herein, the selected train's velocity range is between 50 and 350 km/h, the typical operation speed of either regular or high-speed trains. The numerical results show that the time histories of aerodynamic forces on the train revealed a pattern in tornadic flow variability, the time evolutions of the wind loads on the train were affected by train speeds, and the fluctuation was the greatest when the train ran at 50 km/h. Moreover, the train is subjected to larger aerodynamic forces and moments when it operates along with the rotating vortex flow, especially in the core region, and the train is more dangerous when it runs at a lower speed. The results in this study provide references for assessing operation safety, while a train running on the bridge encounters tornadoes. [ABSTRACT FROM AUTHOR]

The development of high-speed railway networks and the increased running speeds of high-speed trains (HSTs) have made the aerodynamic interference between HSTs and their surrounding environments increasingly important. Compared with a traditional wind tunnel test, systematically understanding the aerodynamic characteristics of HSTs involves relatively more stringent requirements, highlighting the need to develop experimental methods and technologies with enhanced dynamic performance. Central South University (CSU) developed a wireless data acquisition system, named as the in-model sensory and wireless data acquisition — remote control and processing system (ISWDA-RCPS), which can operate onboard a novel moving train and infrastructure rig. The system was developed to meet current wind tunnel data collection needs, and it avoids the physical cables used in conventional devices, which are extremely susceptible to induced noise. The system accepts inputs from various sensors and transfers the data wirelessly to an access point outside a wind tunnel’s test section. To analyze the feasibility of the ISWDA-RCPS concerning its sensing capabilities and wireless communications, we conduct experiments in multiple operating conditions. Finally, pressure measurements are acquired from a moving Fuxing HST model at different points and used to analyze the aerodynamic behavior of the model. [ABSTRACT FROM AUTHOR]

To better understand the aerodynamic characteristics of a train-bridge system under crosswind, an in-house experimental apparatus was developed in a wind tunnel at Central South University (CSU). The new facility consists of trains, a bridge, U-shaped slide rails, and positioning systems with winches. A wireless data acquisition system for pressure measurements was mounted within the train carriage to avoid any potential aerodynamic interference. A 1:25 scaled model of CRH2 running over a simply supported girder bridge was tested in a wind tunnel. The aerodynamic characteristics of the train-bridge system under various combinations of crosswind speed, train speed, and vehicle location on the bridge were identified. The experimental results reveal that the cosine law for surface wind pressure on a train under crosswind is no longer valid when the train runs on the bridge. The moving model method can better capture the more practical aerodynamic characteristics and the impact of train movement on the bridge. The present study indicates that the wind tunnel experiments using the stationary model cannot fully reveal the aerodynamic characteristics of both the train and bridge during crossing. The results captured using this unique approach provide insight into the aerodynamic characteristics of trains and bridges. [ABSTRACT FROM AUTHOR]

High-speed trains (HSTs) are being buffeted by accelerating running speed, and with that comes the aerodynamic issues. The slipstream is related to the train aerodynamic characteristics and of importance to the safety of surrounding people and structures. In this study, the ensemble-averaged and instantaneous characteristics of the slipstream of a simplistic high-speed train model with a square-back were experimentally investigated using a novel moving model rig. The present investigation indicates that the double-line substructure causes obvious asymmetry in the slipstream even at locations apart from the bridge surface with a large distance. The square-back of the HST attenuates its slipstream significantly relative to that with a streamlined tail. Besides, the decaying rate of the slipstream is higher in the wake of a square-back HST. The presents results suggest that the trailing vortices downstream of the square-back HST are substantially suppressed. [ABSTRACT FROM AUTHOR]

With the increase of the running speed of the high-speed train (HST), aerodynamic interference between the HST and surrounding structures becomes more and more important. Traditional wind tunnel experiments using the stationary model can not fully reveal the pulsing behavior of the aerodynamic forces on both the HST and surrounding structures. This paper numerically investigates the aerodynamic characteristics of an HST running on a bridge in cross-wind. The simulation results reveal that when there is no wind barrier, the stationary model case with the yaw angle identical to the moving model case can roughly reproduce the main flow structures around the train. However, once the train runs downstream a wind barrier, the stationary model cannot reveal its aerodynamic characteristics regardless of the yaw angle adopted. The moving model scenario successfully captures the pulsing behavior of the forces on both the train and wind barrier, which is concealed in the cases with a stationary model. The present results indicate that only the moving model method can fully reveal the aerodynamic characteristics and interactions between the train and surrounding structures, especially in evaluating their dynamic response. [ABSTRACT FROM AUTHOR]

The cognitive symptoms of schizophrenia are wide ranging and include impaired goal-directed action. This could be driven by an increase in dopamine transmission in the dorsomedial striatum, a pathophysiological hallmark of schizophrenia. Although commonly associated with psychotic symptoms, dopamine signalling in this region also modulates associative learning that aids in the execution of actions. To gain a better understanding of the role of subcortical dopamine in learning and decision-making, we assessed goal-directed action in male mice using the cross-species outcome-specific devaluation task (ODT). First, we administered systemic amphetamine during training to determine the impact of altered dopaminergic signaling on associative learning. Second, we used pathway-specific chemogenetic approaches to activate the dorsomedial and ventral striatal pathways (that originate in the midbrain) to separately assess learning and performance. Amphetamine treatment during learning led to a dose-dependent impairment in goal-directed action. Activation of both striatal pathways during learning also impaired performance. However, when these pathways were activated during choice, only activation of the ventral pathway impaired goal-directed action. This suggests that elevated transmission in the dorsomedial striatal pathway impairs associative learning processes that guide the goal-directed execution of actions. By contrast, elevated transmission of the ventral striatal pathway disrupts the encoding of outcome values that are important for both associative learning and choice performance. These findings highlight the differential roles of the dorsomedial and ventral inputs into the striatum in goal-directed action and provides insight into how striatal dopamine signaling may contribute to the cognitive problems in those with schizophrenia. • Goal-directed action may be impaired in schizophrenia due to altered dopamine transmission in the dorsomedial striatal pathway, a mechanism which can be explored using animal models. • Systemic administration of amphetamine in male mice during instrumental learning, which predominantly alters brain dopamine levels, impaired goal-directed action. • Chemogenetic activation of separate midbrain inputs into dorsomedial and ventral striatum during learning impaired goal-directed action. • Chemogenetic activation of these same pathways during choice had differential outcomes. Only activation of the ventral striatal pathway impaired goal-directed action. • This study indicates that dopamine and dorsomedial striatal pathway activation may play a role in learning and goal-directed action impairments relevant to schizophrenia. [ABSTRACT FROM AUTHOR]

We present the design, fabrication procedure, and measurement results of Nb superconducting microstrip transmission line resonators fabricated using thin-film polyimide HD-4110, including both nonembedded and embedded versions. These resonators were used to characterize the microwave dielectric loss tangent of 20  $\mu$m thick polyimide HD-4110 at deep cryogenic temperatures. We observed high-quality factors (Q) up to 21 040 at 1.2 K in the frequency range of 2–21 GHz for nonembedded resonators, indicating that the dielectric loss tangent can be less than 5 $\times$10−5. Embedded resonators with an additional 20 $\mu$m thick encapsulation layer also exhibited Q values as high as $\sim 19$ 200. Dielectric and conductor (quasiparticle) loss have been compared between the two types of resonators. This study provides information applicable to the design of future high-density, flexible, multilayer superconducting cables, which are of great interest for potential applications in cryogenic electronics systems, including quantum computers. [ABSTRACT FROM PUBLISHER]

• Aerodynamic characteristics of a typical high-speed railway viaduct under tornado near-ground winds were studied. • Surface pressure coefficients of the bridge deck vary from place to place within the tornado. • Largest side and lift forces occur at the tornado core, but the change patterns of forces in different types with the variation distance. • Research findings are helpful for the design, operation & maintenance of high-speed railway bridges. The tornado is in direct contact with the underlying surface, which causes damage and indicates the vortex structure close to the ground. Accordingly, the maximum wind velocity generally could occur near the ground, potentially exposing the infrastructure to higher wind loads. However, one of the biggest challenges facing tornado research is characterizing the wind structure very near the surface due to the limitation of the data by using Doppler weather Radar. Considering the advantage of the high-fidelity computational fluid dynamics (CFD) models, this study aims to investigate the aerodynamic characteristics of a high-speed railway viaduct under tornado near-surface winds. More specifically, in light of limited full-scale data to arrive at a consensus on quantifying key parameters characterizing the tornado flow and near-surface winds, firstly. Secondly, tornado radar-measured data and a theoretical analysis model were utilized to validate the accuracy of the numerical method adopted in this study. Thirdly, the wind pressure distribution on the bridge is validated using the wind tunnel experimental data in Central South University(CSU), and the comparison between the simulational bridge and the measured data under crosswind was satisfactory. Finally, a comprehensive modeling strategy comprehensively investigates the aerodynamic characteristics of a high-speed railway viaduct under a tornado near-surface wind. [ABSTRACT FROM AUTHOR]

[Display omitted] • A more economical utilization mode of K 2 FeO 4 pretreatment was explored. • Alkaline K 2 FeO 4 pretreatment can effectively increase SCFAs yield. • Effect of pH regulated K 2 FeO 4 pretreatment on phosphorous leaching was analyzed. • A recovery strategy of carbon and phosphorus in sludge was put forward. To improve the dose efficiency of K 2 FeO 4 in waste activated sludge (WAS) treatment, pH regulation on K 2 FeO 4 pretreatment and acidogenic fermentation was investigated. Four pretreatments were compared, i.e. pH3 + 50 g/kg-TS, pH10 + 50 g/kg-TS, neutral pH + 50 g/kg-TS and neutral pH + 100 g/kg-TS (without pH adjustment). The higher short chain fatty acids (SCFAs) yield and phosphorous dissolution rate was found under the condition of pH 10.0. In pH10 + 50 g/kg-TS, the maximum concentration of SCFAs was 5591 mg-COD/L, which yield was 22.6 times higher than that of the neutral pH + 50 g/kg-TS (237 mg COD/L). The acidogenic fermentation period could be shortened to 5 days and acetic acid accounted for 70 % of SCFAs. Furthermore, PO 4 3--P in the hydrolysate (346.5 mg/L) accounted for 47.59 % of TP, which is easier to be recovered by chemical precipitation. Therefore, a more economical and feasible utilization mode of potassium ferrate was proposed. [ABSTRACT FROM AUTHOR]

• The slipstream of the CR400 high-speed train is experimentally investigated by a moving train rig. • Measured by a point cloud of 25-locations, the ensemble-averaged profiles, spatial variations, gusts, and time–frequency characteristics of the slipstream were analyzed. • The spatial–temporal variation in the properties of flow around the head car has been explained regarding the shape of the train. This paper experimentally investigates the characteristics of the velocity field induced by the slipstream from the leading carriage model of a CR 400 high-speed train. The tests were carried out using a 1:16.8 scale model on a moving model rig developed at the Central South University, PRC. The slipstream velocity field was measured at a point cloud involving 25 locations on a plane orthogonal to the track orientation. Aiming at understanding the slipstream ensemble characteristics, especially those unique to the CR400 train, observations were analyzed to evaluate the ensemble-averaged profiles, spatial variations, gusts and time–frequency characteristics of velocity fluctuations in the slipstream. The results suggest that the moving train model and testing rig used in this study capture the unsteady and time-variant features of the slipstream. The spatiotemporal profile of the slipstream usually includes a primary and a secondary peak at the nose tip and the region immediately next to it, respectively. Among the collection of locations studied, the primary peak reaches its maximum at a lateral location close to the train side at the nose height. Finally, the time–frequency portraits of the spatiotemporal variations of the slipstream were obtained using wavelet scalograms of the velocity field, which offered an insightful understanding of the various scales of velocity fluctuations around the nose and their locale. [ABSTRACT FROM AUTHOR]

[Display omitted] • Identified current situation and challenges of high-speed railway aerodynamics. • Aerodynamics of train, bridge, train-bridge system and their factors are discussed. • In-depth review of wind tunnel testing for train, bridge, and train-bridge system. • Discussed limitations of existing experiments and tendencies in applications. • Proposed and developed some platforms for aerodynamic issues of train-bridge system. Wind tunnel tests have been widely applied in aerodynamic investigations owing to their unique advantages. However, it is difficult to theoretically establish a simplified symmetry or two-dimensional model because of the relative motion of the structures and proximity of the train to the ground/infrastructure. Additionally, railway-related aerodynamic problems tend to be more challenging than those encountered in other engineering structures. Moreover, transient and crosswind effects, as well as complex operation environments, need to be considered, thereby making aerodynamic analyses of train–bridge systems challenging. Advanced manufacturing methodologies can reproduce realistic scenarios of high-speed train (HST) operations in a wind tunnel. The development of a controllable and affordable experimental method presents considerable research opportunities and challenges. There exists a strong correlation between wind tunnel experimental methods and the understanding of aerodynamic mechanisms, and some wind tunnel tests are dedicated to identifying the aerodynamic behavior using specific test systems. This study mainly describes the types of tests typically performed in a wind tunnel to analyze the aerodynamic issues of train–bridge systems under wind action. To identify and understand the individual role of the above mentioned-correlated systems, trains and bridges in wind tunnel tests are described separately. High-speed trains on bridges must be made safe and environmentally friendly, and a few cases are presented as indications to reconsider our aerodynamic research priorities. Thus, advanced experimental activities have been proposed in the Central South University (CSU) wind tunnel, representing helpful practices in defining the real-world aerodynamic behavior of wind-vehicle-bridge systems. [ABSTRACT FROM AUTHOR]

Biological sex influences decision-making processes in significant ways, differentiating the responses animals choose when faced with a range of stimuli. The neurobiological underpinnings that dictate sex differences in decision-making tasks remains an important open question, yet single-sex studies of males form most studies in behavioural neuroscience. Here we used female and male BALB/c mice on two spatial learning and memory tasks and examined the expression of perineuronal nets (PNNs) and parvalbumin interneurons (PV) in regions correlated with spatial memory. Mice underwent the aversive active place avoidance (APA) task or the appetitive trial-unique nonmatching-to-location (TUNL) touchscreen task. Mice in the APA cohort learnt to avoid the foot-shock and no differences were observed on key measures of the task nor in the number and intensity of PNNs and PV. On the delay but not separation manipulation in the TUNL task, females received more incorrect trials and less correct trials compared to males. Furthermore, females in this cohort exhibited higher intensity PNNs and PV cells in the agranular and granular retrosplenial cortex, compared to males. These data show that female and male mice perform similarly on spatial learning tasks. However, sex differences in neural circuitry may underly differences in making decisions under conditions of uncertainty on an appetitive task. These data emphasise the importance of using mice of both sexes in studies of decision-making neuroscience. • We used biological sex as a variable to assess spatial memory. • Males and females performed similarly on the active place avoidance task. • Females had altered performance under conditions of uncertainty on the TUNL task. • Females had higher intensity of PNNs and PV cells in the retrosplenial cortex. • Sex differences were only observed on the TUNL task. [ABSTRACT FROM AUTHOR]

We have studied the effects of gamma radiation on flexible superconducting microstrip transmission line structures, to explore their suitability for use in harsh environments where they may be subjected to radiation. In this work, we used two conductor variants: one with only Nb and another with a conductor stack of Al/Nb/Al. Spin-on polyimide HD-4110 was used as the dielectric substrate and both the variants were encapsulated with a layer of HD-4110 to increase the robustness of the structure by protecting the superconducting trace from potential mechanical damage. The resonators were irradiated at room temperature in a vacuum sealed chamber at a pressure of 1E-6 Torr using cobalt-60 as a source of gamma radiation. Samples were exposed to doses up to 60.8 Mrad (608 kGy). Quality factors of the resonators were extracted in the frequency range from 2 to 20 GHz, at various cryogenic temperatures between 1.2 K and 4.2 K, using a closed-cycle cryostat. We observed a small increase in microwave loss for higher temperature ranges, which points to a small change in the superconducting properties of the conductors. The results of this work show that low mass, flexible superconducting cables may be suitable alternatives to bulky coaxial cables for signal transmission at cryogenic temperatures in extreme (radiation) environments. [ABSTRACT FROM AUTHOR]

A foamed starch‐based biomass composite was prepared by the extrusion foaming method with starch, wood fiber and polyvinyl alcohol (PVA) as raw materials. The effects of three additives (plasticizer, cross‐linking agent, and blowing agent) on the mechanical performance of the foamed starch‐based biomass composite were studied, and a three‐layer back‐propagation (BP) artificial neural network model was established for mechanical property prediction. The orthogonal experiment results were used as samples to train the network and predict the mechanical performance of foamed composite. The results show that the proposed BP network model is effective in forecasting the mechanical performance of foamed composite. The appropriate amount of composite plasticizer (glycerin/NaOH) can reduce the crystallinity of the starch; increase the compatibility of the starch，wood fiber and PVA, and increase the tensile strength of the composite to 5.91 MPa. Crosslink reaction occurs between PVA molecular under the reaction of cross‐linking agent borax. The tensile strength of the composite increases up to 6.12 MPa. The tensile strength lowers down as a result of the decrease of the contact area caused emerging bubbles with the help of the blowing agent NaHCO3. POLYM. COMPOS., 40:3923–3928, 2019. © 2019 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Motivated by the inevitable trend of the Internet of Everything, human-machine interaction technology has gradually been permeated into people's daily life. Receptive devices that capture human behaviors and responsive devices that provide machine feedback are key components of human-machine interface. While it is a great challenge to integrate receptive and responsive devices in a well-organized way due to the limitations of material properties and device structures. In this work, we investigate the formation of laser-induced graphene on Nomex paper and propose an efficient interactive strategy based on its piezoresistive and thermoacoustic effects. Functional integration of receiving instructions (pressure-sensing capability) and providing feedback (sound-emitting capability) can be achieved by simply assembling three layers of Nomex paper that have been laser-customized on both sides. The integrated device not only has a sensitive response (∼12 relative current change and ∼50 ms response time) to the pressure similar to a gentle finger press (∼10 kPa), but also can emit a high-quality sound signal with larger sound pressure levels (∼70 dB at 1 W/cm2 power density). Furthermore, two proof-of-concept demonstrations, a press-to-audio pad and a command-responding thermo-earphone, are presented to substantiate the feasibility in information exchange activities. [Display omitted] • Laser-induced graphene layers with favorable electrical conductivity are formed on Nomex paper. • Different conductive properties between double-sided laser-induced graphene across Nomex substrate are obtained by regulating laser power. • Pressure-sensing and sound-emitting capabilities are realized taking advantage of piezoresistive and thermoacoustic effects of laser-induced graphene. • Multifunctional integration is implemented by assembling three-layer Nomex paper that feature double-sided laser-induced graphene. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar accelerated the initiation of methanogenesis and increase methane yield. • Increment of methane yield decreased from 60.6% to 10.4% when increase TS from 5% to 14%. • ARGs reduction was closely associated to the decreased abundance of Proteobacteria. • ARGs abundance in liquid phase was significantly reduced in biochar group. Effects of biochar on co-digestion of pig manure and dewatered sewage sludge under different total solids (TS) were investigated. Biochar could accelerate the start-up of methanogenesis and shorten the adaptation phase. At TS5%, the methane daily production in biochar group was 60.6% higher than the control; nevertheless, when TS increased, the gap between two groups gradually narrowed. Additionally, the change on antibiotics resistance genes (ARGs) was also affected by TS and the biochar addition. Moreover, biochar was beneficial to reduce ARGs in liquid phase. At TS14%, the total ARGs abundance in the liquid phase of biochar group was 41.4% lower than the control, among which the reduction rates of etB(P), sul1, rpoB2, macA, mupA and mupB were more prominent. These findings could provide useful guidance for developing ARGs elimination strategy before their release into the environment. [ABSTRACT FROM AUTHOR]

Laser engraving is carried out on the both sides of PI film to achieve constant temperature gas monitor and early automatic self-alarm. [Display omitted] • The LIG IDEs serve gas sensor, and rectangular LIG is usable in dual-working mode. • The rectangular LIG provides a constant working temperature under a DC voltage. • The NO 2 monitor with heating condition overcomes the inability to desorb at RT. • Let the device emit an acoustic alarm once NO 2 concentration is beyond threshold. The increasingly serious air pollution problem makes the development of high-performance gas monitoring system extremely urgent. Especially for nitrogen dioxide (NO 2), which is harmful to both people and the environment. The combination of reliable real-time monitoring and early warning is of great significance yet less study. Here, we designed a laser-induced graphene (LIG)-based multi-functional NO 2 monitor and self-alarm (MMSA), in which a rectangle area is used as a dual-functional module to realize high-performance temperature condition and acoustic alarm by applying direct/alternating current voltage excitation source. The molybdenum disulfide (MoS 2) sensitive material works in concert with the LIG interdigital electrodes (IDEs), and the gas monitor achieves high sensitivity (86.81% for 5 ppm, and 22.90% for 250 ppb) and excellent recoverability, aided by the good electrothermal property of LIG, overcoming the dilemma of poor sensing performance of MoS 2 at room temperature (RT). To top it off, the thermoacoustic effect of the LIG could bring about an intuitional sound signal, and a proof-of-concept demonstrates the timely acoustic warning response of the MMSA to exceeded NO 2 concentrations. [ABSTRACT FROM AUTHOR]

Visual optical information encryption–decryption and anti‐counterfeiting (IEDAC) technology play a vital role in the field of information security. Recent luminescent information encryption technologies face the disadvantages of depending on external large‐scale stimulus decryption equipment, inability to read out repeatedly, and information leakage, impeding the practical applications of luminescence encryption. Here, an integrated luminescent IEDAC chip is proposed, which provides a convenient approach to store and decipher pre‐patterned luminescence information based on laser engraved template and film heater. The luminescent encryption chip contains a double‐layer structure made up of long persistent phosphors based on SrCaGa4O8 host and a laser induced graphene heater, which makes it possible to decrypt information on a single chip. This design enables dual‐mode (photoluminescence/long persistent luminescence), dual‐color (blue/yellow‐green), and multi‐level IEDAC function, providing a novel insight and integrated strategy for implementing advanced IEDAC technologies. [ABSTRACT FROM AUTHOR]

Real-time monitoring of SF6 status is of exceptional importance to ensure stable operation of the power system, to promptly diagnose whether an insulation failure has occurred and to assess the severity. Considering the excellent physicochemical properties and insulation defects of hexagonal boron nitride, the strategy of surface modification, namely, hydrogenation, fluorination, and combinations of the two ways, is proposed to improve its chemical activity, and the gas-sensing potential of the most effective one is investigated using density functional theory. The typical adsorption models of SF6 decomposition component gases on the surface of F-BN-H are constructed, and the most stable adsorption structures with their density of states, molecular orbitals, and sensing responses are analyzed. The results show that F-BN-H has good sensitivity to decomposition components of SF6. To be specific, SO2 and SOF2 have good adsorption properties, prominent charge transfer, and distinct change in electronic properties. The response of gas adsorption can be detected timely by the change in conductivity, and, additionally, the adsorbent has fast desorption capacity at room temperature. These results indicate that the F-BN-H-based gas sensor is a qualified potential candidate with dependable application and recoverability for detecting SF6 decomposition in high-voltage insulated equipment. [ABSTRACT FROM AUTHOR]

Compared with MoS 2 monolayer, the SV-MoS 2 monolayer improves the absorbability toward SF 6 decomposition products and increases the selectivity of SO 2 F 2. [Display omitted] • The investigation about sulfuric vacancy in two-dimensional molybdenum disulfide monolayer. • The adsorption behavior of typical SF 6 decomposition components on SV-MoS 2 monolayer is shown. • The physical sensing properties and mechanism of adsorption system are fully analyzed. A long-running SF 6 insulating gas decomposes without being detected in time would cause incalculable consequences, therefore, real-time monitoring towards SF 6 status is of practical significance. Currently, the gas-sensitive properties of two-dimensional materials are the focus and hotspot of gas sensor research, however, in practical situations, material preparation and device fabrication will inevitably bring about defects. Therefore, the effects of sulfuric vacancy (SV) in molybdenum disulphide are proposed and explored, and a comparative study of gas-sensitive properties (pristine MoS 2 vs SV- MoS 2) is carried out using density functional theory based on the first principles. Constructing typical adsorption models for SF 6 decomposition components on monolayer, together with analyzing the optimum adsorption structures, adsorption energy, density of states, molecular orbitals, electrical conductivity and co-adsorption behaviors. The results show that the SV brings a defective state to MoS 2 monolayer, which contributes to an overall increase in the adsorption energy for the decomposition components (the increase > 0.15 eV), making the undifferentiated adsorption effect selective for SO 2 F 2. The physical interaction between the decomposition products and SV-MoS 2 monolayer is more favorable for desorption. These results indicate it is appropriate for detecting SF 6 status in high-voltage insulation environments, with pointers to practical applications for two-dimensional materials. [ABSTRACT FROM AUTHOR]