期刊文献+
共找到247,405篇文章
< 1 2 250 >
每页显示 20 50 100
Experimental investigation on coal pore-fracture variation and fractal characteristics synergistically affected by solvents for improving clean gas extraction 被引量:1
1
作者 Feilin Han Sheng Xue +3 位作者 Chunshan Zheng Zhongwei Chen Guofu Li Bingyou Jiang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期413-425,共13页
Chemical solvents instead of pure water being as hydraulic fracturing fluid could effectively increase permeability and improve clean methane extraction efficiency.However,pore-fracture variation features of lean coal... Chemical solvents instead of pure water being as hydraulic fracturing fluid could effectively increase permeability and improve clean methane extraction efficiency.However,pore-fracture variation features of lean coal synergistically affected by solvents have not been fully understood.Ultrasonic testing,nuclear magnetic resonance analysis,liquid phase mass spectrometry was adopted to comprehensively analyze pore-fracture change characteristics of lean coal treated by combined solvent(NMP and CS_(2)).Meanwhile,quantitative characterization of above changing properties was conducted using geometric fractal theory.Relationship model between permeability,fractal dimension and porosity were established.Results indicate that the end face fractures of coal are well developed after CS2and combined solvent treatments,of which,end face box-counting fractal dimensions range from 1.1227 to 1.4767.Maximum decreases in ultrasonic longitudinal wave velocity of coal affected by NMP,CS_(2)and combined solvent are 2.700%,20.521%,22.454%,respectively.Solvent treatments could lead to increasing amount of both mesopores and macropores.Decrease ratio of fractal dimension Dsis 0.259%–2.159%,while permeability increases ratio of NMR ranges from 0.1904 to 6.4486.Meanwhile,combined solvent could dissolve coal polar and non-polar small molecules and expand flow space.Results could provide reference for solvent selection and parameter optimization of permeability-enhancement technology. 展开更多
关键词 Clean gas extraction Chemical solvent experimental investigation Fractal characteristics Pore fracture
下载PDF
Experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering boundary effect
2
作者 Xuwei Wang Yeshuang Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期1072-1084,共13页
The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundar... The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundary effect is conducted,where the hydraulic head difference(DH)varies,and the boundary includes non-loss and soil-loss conditions.Soil samples are filled into seven soil storerooms connected in turn.After evaluation,the variation in content of fine sand(ΔR_(f))and the hydraulic conductivity of soils in each storeroom(C_(i))are analyzed.In the non-loss test,the soil sample filling area is divided into runoff,transited,and accumulated areas according to the negative or positive ΔR_(f) values.ΔR_(f) increases from negative to positive along the seepage path,and Ci decreases from runoff area to transited area and then rebounds in accumulated area.In the soil-loss test,all soil sample filling areas belong to the runoff area,where the gentle-loss,strengthened-loss,and alleviated-loss parts are further divided.ΔR_(f) decreases from the gentle-loss part to the strengthened-loss part and then rebounds in the alleviated-loss part,and C_(i) increases and then decreases along the seepage path.The relationship between ΔR_(f) and Ci is different with the boundary condition.Ci exponentially decreases with ΔR_(f) in the non-loss test and increases with ΔR_(f) generally in the soil-loss test. 展开更多
关键词 Suffusion PERMEABILITY experimental investigation Boundary effect Horizontal seepage
下载PDF
Experimental investigation of dynamic characteristics of leaching tubing for solution mining of salt cavern carbon and energy storage
3
作者 Yin-Ping Li Xin-Bo Ge +1 位作者 Xi-Lin Shi Hong-Ling Ma 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2703-2722,共20页
Salt caverns are extensively utilized for storing various substances such as fossil energy,hydrogen,compressed air,nuclear waste,and industrial solid waste.In China,when the salt cavern is leached through single-well ... Salt caverns are extensively utilized for storing various substances such as fossil energy,hydrogen,compressed air,nuclear waste,and industrial solid waste.In China,when the salt cavern is leached through single-well water solution mining with oil as a cushion,engineering challenges arise with the leaching tubing,leading to issues like damage and instability.These problems significantly hinder the progress of cavern construction and the control of cavern shape.The primary cause of this is the flowinduced vibration instability of leaching tubing within a confined space,which results in severe bending or damage to the tubing.This study presents a model experimental investigation on the dynamic characteristics of leaching tubing using a self-developed liquid-solid coupling physical model experiment apparatus.The experiment utilizes a silicone-rubber pipe(SRP)and a polycarbonate pipe(PCP)to examine the effects of various factors on the dynamic stability of cantilevered pipes conveying fluid.These factors include external space constraint,flexural rigidity,medium outside the pipe,overhanging length,and end conditions.The experiments reveal four dynamic response phenomena:water hammer,static buckling,chaotic motion,and flutter instability.The study further demonstrates that the length of the external space constraint has a direct impact on the flutter critical flow velocity of the cantilevered pipe conveying fluid.Additionally,the flutter critical flow velocity is influenced by the end conditions and different external media. 展开更多
关键词 Salt cavern storage Solution mining Leaching tubing experimental investigation Flutter instability
下载PDF
Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis
4
作者 Li Yuchun Shen Chao +1 位作者 Liu Wei Li Dong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期445-454,共10页
The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this study.An auto-parametric resonance experiment of the ... The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this study.An auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on columns.The parametric vibration equation is established for the test model using the finite-element method.The auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent method.The effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test model.Compared with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental ones.For a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric resonance.Combined with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed. 展开更多
关键词 auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge
下载PDF
Experimental Investigation of a Phase-ChangeMaterial’s Stabilizing Role in a Pilot of Smart Salt-Gradient Solar Ponds
5
作者 Karim Choubani Ons Ghriss +2 位作者 Nashmi H.Alrasheedi Sirin Dhaoui Abdallah Bouabidi 《Frontiers in Heat and Mass Transfer》 EI 2024年第1期341-358,共18页
Faced with the world’s environmental and energy-related challenges,researchers are turning to innovative,sustainable and intelligent solutions to produce,store,and distribute energy.This work explores the trend of us... Faced with the world’s environmental and energy-related challenges,researchers are turning to innovative,sustainable and intelligent solutions to produce,store,and distribute energy.This work explores the trend of using a smart sensor to monitor the stability and efficiency of a salt-gradient solar pond.Several studies have been conducted to improve the thermal efficiency of salt-gradient solar ponds by introducing other materials.This study investigates the thermal and salinity behaviors of a pilot of smart salt-gradient solar ponds with(SGSP)and without(SGSPP)paraffin wax(PW)as a phase-change material(PCM).Temperature and salinity were measured experimentally using a smart sensor,with the measurements being used to investigate the stabilizing effects of placing the PCM in the solar pond’s lower convective zone.The experimental results show that the pond with the PCM(SGSPP)achieved greater thermal and salinity stability,with there being a lesser temperature and salinity gradient between the different layers when compared to a solar pond without thePCM(SGSP).The use of the PCM,therefore,helped control the maximum and minimum temperature of the pond’s storage zone.The UCZ has been found to operate approximately 4 degrees above the average ambient temperature of the day in the SGSPP and 7 degrees in SGSP.Moreover,an unstable situation is generated after 5 days from starting the operation and at 1.9 m from the bottom,and certain points have the tendency to be neutral from the upper depths in 1,3 m of the bottom. 展开更多
关键词 Smart salt-gradient solar pond phase-change material experimental investigation stability of solar ponds
下载PDF
Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining
6
作者 LIU Lei LIU Jian-cheng +2 位作者 LI Xin XU Li-xin ZHANG Xiu-zhan 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期42-53,共12页
Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on land.Vertical hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for... Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on land.Vertical hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial applications.In the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle velocity.The hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow velocities.During transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture velocity.The qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were investigated.The local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic gradient.The effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport. 展开更多
关键词 deepsea mining vertical hydraulic transport experiment flow characteristics
下载PDF
Theoretical and experimental investigations on an X-shaped vibration isolator with active controlled variable stiffness
7
作者 Zeyu CHAI J.T.HAN +3 位作者 Xuyuan SONG Jian ZANG Yewei ZHANG Zhen ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第8期1371-1386,共16页
A novel X-shaped variable stiffness vibration isolator(X-VSVI)is proposed.The Runge-Kutta method,harmonic balance method,and wavelet transform spectra are introduced to evaluate the performance of the X-VSVI under var... A novel X-shaped variable stiffness vibration isolator(X-VSVI)is proposed.The Runge-Kutta method,harmonic balance method,and wavelet transform spectra are introduced to evaluate the performance of the X-VSVI under various excitations.The layer number,the installation angle of the X-shaped structure,the stiffness,and the active control parameters are systematically analyzed.In addition,a prototype of the X-VSVI is manufactured,and vibration tests are carried out.The results show that the proposed X-VSVI has a superior adaptability to that of a traditional X-shaped mechanism,and shows excellent vibration isolation performance in response to different amplitudes and forms of excitations.Moreover,the vibration isolation efficiency of the device can be improved by appropriate adjustment of parameters. 展开更多
关键词 bionic vibration isolation X-shaped structure variable stiffness structure nonlinear dynamics prototype experiment
下载PDF
Experimental Investigation of Wave-Current Loads on a Bridge Shuttle-Shaped Cap–Pile Foundation
8
作者 Chenkai Hong Zhongda Lyu +2 位作者 Fei Wang Zhuo Zhao Lei Wang 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1565-1592,共28页
To scrutinize the characteristics of wave-current loads on a bridge shuttle-shaped cap–pile foundation,a 1:125 test model was considered in a laboratory flume.The inline,transverse and vertical wave–current forces a... To scrutinize the characteristics of wave-current loads on a bridge shuttle-shaped cap–pile foundation,a 1:125 test model was considered in a laboratory flume.The inline,transverse and vertical wave–current forces acting on the shuttle-shaped cap-pile group model were measured considering both random waves and a combination of random waves with a current.The experimental results have shown that the wave-current forces can be well correlated with the wave height,the wavelength,the current velocity,the incident direction and the water level in the marine environment.An increase in the current velocity can lead to a sharp increase in the inline and transverse wave-current forces,while the vertical wave-current force decreases.Moreover,the wave-current forces are particularly strong when a combination of high tide,strong wave and strong current is considered. 展开更多
关键词 Shuttle-shaped cap-pile foundation wave-current force wave flume experiment sea-crossing bridge
下载PDF
Theoretical and experimental investigation of the resonance responses and chaotic dynamics of a bistable laminated composite shell in the dynamic snap-through mode
9
作者 Meiqi WU Pengyu LV +3 位作者 Hongyuan LI Jiale YAN Huiling DUAN Wei ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第4期581-602,共22页
The dynamic model of a bistable laminated composite shell simply supported by four corners is further developed to investigate the resonance responses and chaotic behaviors.The existence of the 1:1 resonance relations... The dynamic model of a bistable laminated composite shell simply supported by four corners is further developed to investigate the resonance responses and chaotic behaviors.The existence of the 1:1 resonance relationship between two order vibration modes of the system is verified.The resonance response of this class of bistable structures in the dynamic snap-through mode is investigated,and the four-dimensional(4D)nonlinear modulation equations are derived based on the 1:1 internal resonance relationship by means of the multiple scales method.The Hopf bifurcation and instability interval of the amplitude frequency and force amplitude curves are analyzed.The discussion focuses on investigating the effects of key parameters,e.g.,excitation amplitude,damping coefficient,and detuning parameters,on the resonance responses.The numerical simulations show that the foundation excitation and the degree of coupling between the vibration modes exert a substantial effect on the chaotic dynamics of the system.Furthermore,the significant motions under particular excitation conditions are visualized by bifurcation diagrams,time histories,phase portraits,three-dimensional(3D)phase portraits,and Poincare maps.Finally,the vibration experiment is carried out to study the amplitude frequency responses and bifurcation characteristics for the bistable laminated composite shell,yielding results that are qualitatively consistent with the theoretical results. 展开更多
关键词 bistable laminated composite shell dynamic snap-through mode Hopf bifurcation chaotic dynamics vibration experiment
下载PDF
Experimental Investigation on the Strength and Ductility Performance of Steel-Timber-Steel Joints with Screw and Steel-Tube Fasteners
10
作者 Huifeng Yang Mingwang Wu +3 位作者 Rixin Gu Hang Cao Kai Xiao Benkai Shi 《Journal of Renewable Materials》 EI 2023年第12期4175-4195,共21页
This article presents experimental results of steel-timber-steel(STS)joints loaded parallel to grain.Eight groups of specimens were designed,and tensile tests were performed.The fastener types and fastener numbers wer... This article presents experimental results of steel-timber-steel(STS)joints loaded parallel to grain.Eight groups of specimens were designed,and tensile tests were performed.The fastener types and fastener numbers were considered to evaluate the tensile strengths and ductility performances of the STS joints.The screws with 6 mm diameter and the innovative steel-tubes with 18 mm diameter were adopted as connecting fasteners.The experimental results were discussed in terms of yielding and ultimate strengths,slip stiffness,and ductility factors.The ductility classification and failure mechanisms of each group of specimens were analyzed.It was demonstrated that the STS joint with large diameter steel-tubes showed acceptable ductility,which was close to the ductility of the STS joint with small diameter screws,thanks to the hollow structure of the steel-tube.The theoretical strengths of various failure modes for the joints with small diameter screws or large diameter steel-tubes were calculated and compared with the experimental results.The ductile performance of the STS joint was discussed by comparing the theoretical strengths of various failure modes.The effective number of the STS joint with multifasteners was also analyzed by considering the failure mechanisms in aspects of tensile strength and slip stiffness. 展开更多
关键词 Steel-timber-steel joint SCREW steel-tube DUCTILITY experimental investigation timber structure
下载PDF
Experimental investigation and flow analysis of clear-water scour around pier and abutment in proximity 被引量:1
11
作者 Mohammad Saeed Fakhimjoo Abdollah Ardeshir +1 位作者 Kourosh Behzadian Hojat Karami 《Water Science and Engineering》 EI CAS CSCD 2023年第1期94-105,共12页
Local scour around bridge piers and abutments is one of the most significant causes of bridge failure.Despite a plethora of studies on scour around individual bridge piers or abutments,few studies have focused on the ... Local scour around bridge piers and abutments is one of the most significant causes of bridge failure.Despite a plethora of studies on scour around individual bridge piers or abutments,few studies have focused on the joint impact of a pier and an abutment in proximity to one another on scour.This study conducted laboratory experiments and flow analyses to examine the interaction of piers and abutments and their effect on clear-water scour.The experiments were conducted in a rectangular laboratory flume.They included 18 main tests(with a combination of different types of piers and abutments)and five control tests(with individual piers or abutments).Three pier types(a rectangular pier with a rounded edge,a group of three cylindrical piers,and a single cylindrical pier)and two abutment types(a wingewall abutment and a semicircular abutment)were used.An acoustic Doppler velocimeter was used to measure the three-dimensional flow velocity for analyses of streamline,velocity magnitude,vertical velocity,and bed shear stress.The results showed that the velocity near the pier and abutment increased by up to 80%.The maximum scour depth around the abutment increased by up to 19%.In contrast,the maximum scour depth around the pier increased significantly by up to l71%.The presence of the pier in the vicinity of the abutment led to an increase in the scour hole volume by up to 87%relative to the case with a solitary abutment.Empirical equations were also derived to accurately estimate the maximum scour depth at the pier adjacent to the abutment. 展开更多
关键词 ABUTMENT ADV Bridge scour Laboratory experiment Maximum scour depth PIER
下载PDF
Flume Experiment Investigation on Propagation Characteristics of Tidal Bore in A Curved Channel 被引量:1
12
作者 FAN Jun TAO Ai-feng +2 位作者 SHI Mo-quan LI Ying PENG Ji 《China Ocean Engineering》 SCIE EI CSCD 2023年第1期131-144,共14页
Tidal bore is a special and intensive form of flow movement induced by tidal effect in estuary areas, which has complex characteristics of profile, propagation and flow velocity. Although it has been widely studied fo... Tidal bore is a special and intensive form of flow movement induced by tidal effect in estuary areas, which has complex characteristics of profile, propagation and flow velocity. Although it has been widely studied for the generation mechanism, propagation features and influencing factors, the curved channel will complicate the characteristics of tidal bore propagation, which need further investigation compared with straight channel. In this study, the flume experiments for both undular and breaking bores’ propagation in curved channel are performed to measure the freesurface elevation and flow velocity by ultrasonic sensors and ADV respectively. The propagation characteristics,including tidal bore height, cross-section surface gradient, tidal bore propagation celerity, and flow velocity are obtained for both sides of the curved channel. And three bore intensities are set for each type of tidal bores. The freesurface gradients are consistently enlarged in high-curvature section for undular and breaking bores, but have distinct behaviors in low-curvature section. The spatial distributions of tidal bore propagation celerity and flow velocity are compared between concave and convex banks. This work will provide experimental reference for engineering design of beach and seawall protection, erosion reduction and siltation promotion in estuary areas with the existence of tidal bores. 展开更多
关键词 tidal bore curved channel flume experiment propagation celerity bore intensity
下载PDF
Exploration of playa surface crusts in Qehan Lake, China through field investigation and wind tunnel experiments 被引量:1
13
作者 LIU Dongwei HAN Lijing +2 位作者 KOU Zihan GAO Xinyu WANG Jingjing 《Journal of Arid Land》 SCIE CSCD 2023年第5期491-507,共17页
Globally,many lakes are drying up,leaving exposed lakebeds where wind erosion releases dust and sand rich in salt and harmful heavy metals into the atmosphere.Therefore,understanding the characteristics and spatial di... Globally,many lakes are drying up,leaving exposed lakebeds where wind erosion releases dust and sand rich in salt and harmful heavy metals into the atmosphere.Therefore,understanding the characteristics and spatial distribution of playa surface crusts is important to recognize the manifestation of salt dust storms.The objective of this study was to explore the playa surface crust types as well as their spatial distribution and evolution of Qehan Lake in Inner Mongolia Autonomous Region,China to understand the salt dust release potential of different types of playa surface crusts.Various crust characteristics were investigated by field sampling in Qehan Lake,and playa surface crusts were further divided into five types:vegetated areas,salt crusts,clay flats,curly crusts,and margins.It should be noted that curly crusts were distributed in clay flats and covered only a small area in Qehan Lake.The spatial distribution characteristics of playa surface crust types were obtained by supervised classification of remote sensing images,and the salt dust release potential of crusts was explored by the wind tunnel experiments.The field investigation of Qehan Lake revealed that playa surface crust types had a circum-lake band distribution from the inside to the outside of this lake,which were successively vegetated areas,clay flats,salt crusts,and margins.The spatial distribution patterns of playa surface crust types were mainly controlled by the hydrodynamics of the playa,soil texture,and groundwater.There was a significant negative correlation between crust thickness and electrical conductivity.The results of the wind tunnel experiments showed that the initial threshold of friction wind velocity for the salt dust release was higher in clay flats(0.7–0.8 m/s)than in salt crusts(0.5–0.6 m/s).Moreover,the particle leap impact processes occurring under natural conditions may reduce this threshold value.Salinity was the main factor controlling the difference in the initial threshold of friction wind velocity for the salt dust release of clay flats and salt crusts.This study provides a scientific reference for understanding how salt dust is released from a lakebed,which may be used for ecological restoration of dry salt lakes. 展开更多
关键词 playa surface crust curly crusts salt crusts salt dust release wind tunnel experiments Qehan Lake
下载PDF
Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation 被引量:2
14
作者 Xiao Xue Deyu Zhou +5 位作者 Xiangning Yu Gang Wang Juanjuan Li Xia Xie Lizhen Cui Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1022-1038,共17页
Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a nove... Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”. 展开更多
关键词 Agent-based modeling computational experiments cyber-physical-social systems(CPSS) generative deduction generative experiments meta model
下载PDF
Investigation of the epidemiology,pathogenicity and immunogenicity of Bordetella bronchiseptica isolated from cats and dogs in China from 2021 to 2023 被引量:1
15
作者 Qinghua Shang Wenhui Gao +7 位作者 Xiangting Zhang Jianqing Zhao Ying Wu Haoqi Li Ming Zhou Zhen F.Fu Chengguang Zhang Ling Zhao 《Animal Diseases》 CAS 2024年第3期156-172,共17页
Bordetella bronchiseptica(Bb)is recognized as a leading cause of respiratory diseases in dogs and cats.However,epidemiological data on Bb in dogs and cats in China are still limited,and there is no commercially availa... Bordetella bronchiseptica(Bb)is recognized as a leading cause of respiratory diseases in dogs and cats.However,epidemiological data on Bb in dogs and cats in China are still limited,and there is no commercially available vaccine.Live vaccines containing Bb that are widely used abroad are generally efective but can establish latency and potentially reactivate to cause illness in some immunodefcient vaccinated recipients,raising safety concerns.In this study,34 canine-derived and two feline-derived Bb strains were isolated from 1809 canine and 113 feline nasopharyngeal swab samples collected from eight provinces in China from 2021 to 2023.The PCR results showed that the percentage of positive Bb was 22.94%(441/1922),and more than 90%of the Bb isolates had four virulence factor-encoding genes(VFGs),namely,fhaB,prn,betA and dnt.All the isolated strains displayed a multidrug-resistant phenotype.The virulence of 10 Bb strains isolated from dogs with respiratory symptoms was tested in mice,and we found that eight isolates were highly virulent.Furthermore,the eight Bb isolates with high virulence were inactivated and intramuscularly injected into mice,and three Bb strains(WH1218,WH1203 and WH1224)with the best protective efcacy were selected.Dogs immunized with these three strains exhibited strong protection against challenge with the Bb feld strain WH1218.Ultimately,the WH1218 strain with the greatest protection in dogs was selected as the vaccine candidate.Dogs and cats that received a vaccine containing 109 CFU of the inactivated WH1218 strain showed complete protection against challenge with the Bb feld strain WH1218.This study revealed that Bb is an important pathogen that causes respiratory diseases in domestic dogs and cats in China,and all the isolates exhibited multidrug resistance.The present work contributes to the current understanding of the prevalence,antimicrobial resistance,and virulence genes of Bb in domestic dogs and cats.Additionally,our results suggest that the WH1218 strain is a promising candidate safe and efcacious inactivated Bb vaccine. 展开更多
关键词 Bordetella bronchiseptica Epidemiological investigation PATHOGENICITY IMMUNOGENICITY Inactivated vaccine
下载PDF
Gazing through the bubble:an experimental investigation into financial risk‑taking using eye‑tracking
16
作者 Filip‑Mihai Toma Cosmin‑Octavian Cepoi +1 位作者 Matei Nicolae Kubinschi Makoto Miyakoshi 《Financial Innovation》 2023年第1期750-776,共27页
Eye tracking can facilitate understanding irrational decision-making in contexts such as financial risk-taking.For this purpose,we develop an experimental framework in which participants trade a risky asset in a simul... Eye tracking can facilitate understanding irrational decision-making in contexts such as financial risk-taking.For this purpose,we develop an experimental framework in which participants trade a risky asset in a simulated bubble market to maximize individual returns while their eye movements are recorded.Returns are sensitive to eye movement dynamics,depending on the presented visual stimuli.Using eye-tracking data,we investigated the effects of arousal,attention,and disengagement on individual payoffs using linear and nonlinear approaches.By estimating a nonlinear model using attention as a threshold variable,our results suggest that arousal positively influences trading returns,but its effect becomes smaller when attention exceeds a certain threshold,whereas disengagement has a higher negative impact on reduced attention levels and becomes almost irrelevant when attention increases.Hence,we provide a neurobehavioral metric as a function of attention that predicts financial gains in boomand-bust scenarios.This study serves as a proof-of-concept for developing future psychometric measures to enhance decision-making. 展开更多
关键词 Financial bubble experiment Risk-taking EYE-TRACKING ATTENTION AROUSAL
下载PDF
Predicting the probability distribution of Martian rocks mechanical property based on microscale rock mechanical experiments and accurate grain-based modeling 被引量:1
17
作者 Shuohui Yin Yingjie Wang Jingang Liu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1327-1339,共13页
The exploration of Mars would heavily rely on Martian rocks mechanics and engineering technology.As the mechanical property of Martian rocks is uncertain,it is of utmost importance to predict the probability distribut... The exploration of Mars would heavily rely on Martian rocks mechanics and engineering technology.As the mechanical property of Martian rocks is uncertain,it is of utmost importance to predict the probability distribution of Martian rocks mechanical property for the success of Mars exploration.In this paper,a fast and accurate probability distribution method for predicting the macroscale elastic modulus of Martian rocks was proposed by integrating the microscale rock mechanical experiments(micro-RME),accurate grain-based modeling(AGBM)and upscaling methods based on reliability principles.Firstly,the microstructure of NWA12564 Martian sample and elastic modulus of each mineral were obtained by micro-RME with TESCAN integrated mineral analyzer(TIMA)and nanoindentation.The best probability distribution function of the minerals was determined by Kolmogorov-Smirnov(K-S)test.Secondly,based on best distribution function of each mineral,the Monte Carlo simulations(MCS)and upscaling methods were implemented to obtain the probability distribution of upscaled elastic modulus.Thirdly,the correlation between the upscaled elastic modulus and macroscale elastic modulus obtained by AGBM was established.The accurate probability distribution of the macroscale elastic modulus was obtained by this correlation relationship.The proposed method can predict the probability distribution of Martian rocks mechanical property with any size and shape samples. 展开更多
关键词 Probability distribution Martian rocks Microscale rock mechanic experiment Nanoindentation Accurate grain-based modeling
下载PDF
Network pharmacology study and in vitro experimental validation of Xiaojianzhong decoction against gastric cancer 被引量:1
18
作者 Guo-Qing Chen Yi Nan +6 位作者 Na Ning Shi-Cong Huang Yu-Ting Bai Zi-Ying Zhou Gu Qian Wei-Qiang Li Ling Yuan 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第9期3932-3954,共23页
BACKGROUND Cancer is one of the most serious threats to human health worldwide.Conventional treatments such as surgery and chemotherapy are associated with some drawbacks.In recent years,traditional Chinese medicine t... BACKGROUND Cancer is one of the most serious threats to human health worldwide.Conventional treatments such as surgery and chemotherapy are associated with some drawbacks.In recent years,traditional Chinese medicine treatment has been increasingly advocated by patients and attracted attention from clinicians,and has become an indispensable part of the comprehensive treatment for gastric cancer.AIM To investigate the mechanism of Xiaojianzhong decoction(XJZ)in the treatment of gastric cancer(GC)by utilizing network pharmacology and experimental validation,so as to provide a theoretical basis for later experimental research.METHODS We analyzed the mechanism and targets of XJZ in the treatment of GC through network pharmacology and bioinformatics.Subsequently,we verified the impact of XJZ treatment on the proliferative ability of GC cells through CCK-8,apoptosis,cell cycle,and clone formation assays.Additionally,we performed Western blot analysis and real-time quantitative PCR to assess the protein and mRNA expression of the core proteins.RESULTS XJZ mainly regulates IL6,PTGS2,CCL2,MMP9,MMP2,HMOX1,and other target genes and pathways in cancer to treat GC.The inhibition of cell viability,the increase of apoptosis,the blockage of the cell cycle at the G0/G1 phase,and the inhibition of the ability of cell clone formation were observed in AGS and HGC-27 cells after XJZ treatment.In addition,XJZ induced a decrease in the mRNA expression of IL6,PTGS2,MMP9,MMP2,and CCL2,and an increase in the mRNA expression of HOMX1.XJZ significantly inhibited the expression of IL6,PTGS2,MMP9,MMP2,and CCL2 proteins and promoted the expression of the heme oxygenase-1 protein.CONCLUSION XJZ exerts therapeutic effects against GC through multiple components,multiple targets,and multiple pathways.Our findings provide a new idea and scientific basis for further research on the molecular mechanisms underlying the therapeutic effects of XJZ in the treatment of GC. 展开更多
关键词 Xiaojianzhong decoction Gastric cancer Network pharmacology Molecular mechanism In vitro experiment
下载PDF
Experimental investigation of dynamic stall flow control using a microsecond-pulsed plasma actuator
19
作者 徐泽阳 武斌 +2 位作者 高超 王娜 贾天昊 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第3期193-203,共11页
To alleviate the performance deterioration caused by dynamic stall of a wind turbine airfoil,the flow control by a microsecond-pulsed dielectric barrier discharge(MP-DBD) actuator on the dynamic stall of a periodicall... To alleviate the performance deterioration caused by dynamic stall of a wind turbine airfoil,the flow control by a microsecond-pulsed dielectric barrier discharge(MP-DBD) actuator on the dynamic stall of a periodically pitching NACA0012 airfoil was investigated experimentally.Unsteady pressure measurements with high temporal accuracy were employed in this study,and the unsteady characteristics of the boundary layer were investigated by wavelet packet analysis and the moving root mean square method based on the acquired pressure.The experimental Mach number was 0.2,and the chord-based Reynolds number was 870 000.The dimensionless actuation frequencies F+ were chosen to be 0.5,1,2,and 3,respectively.For the light dynamic regime,the MP-DBD plasma actuator plays the role of suppressing flow separation from the trial edge and accelerating the flow reattachment due to the high-momentum freestream flow being entrained into the boundary layer.Meanwhile,actuation effects were promoted with the increasing dimensionless actuation frequency F+.The control effects of the deep dynamic stall were to delay the onset and reduce the strength of the dynamic stall vortex due to the accumulating vorticity near the leading edge being removed by the induced coherent vortex structures.The laminar fluctuation and Kelvin-Helmholtz(K-H) instabilities of transition and relaminarization were also mitigated by the MP-DBD actuation,and the alleviated K-H rolls led to the delay of the transition onset and earlier laminar reattachment,which improved the hysteresis effect of the dynamic stall.For the controlled cases of F+=2,and F+=3,the laminar fluctuation was replaced by relatively low frequency band disturbances corresponding to the harmonic responses of the MP-DBD actuation frequency. 展开更多
关键词 microsecond-pulsed plasma actuator dielectric barrier discharge flow control dynamic stall wind turbine wind tunnel experiment
下载PDF
Design and analysis of an advanced thermal management system for the solar close observations and proximity experiments spacecraft 被引量:1
20
作者 Liu Liu Kangli Bao +4 位作者 Jianchao Feng Xiaofei Zhu Haoyu Wang Xiaofeng Zhang Jun Lin 《Astronomical Techniques and Instruments》 CSCD 2024年第1期52-61,共10页
In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relat... In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs. 展开更多
关键词 Solar Close Observations and Proximity experiments Adaptive thermal control method Thermal field planning method Pumped liquid cooling system Advanced thermal management system
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部