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Finite deformation analysis of the rotating cylindrical hollow disk composed of functionally-graded incompressible hyper-elastic material

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Applied Mathematics and Mechanics(English Edition) 2023年第8期44卷 1367-1384页

作者： libiao XIN Yang WANG zhiqiang li Y.B.li College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Aeronautics and Astronautics Taiyuan University of TechnologyTaiyuan 030024China Department of Mechanical and Aerospace Engineering North Carolina State UniversityRaleighNC 27606U.S.A.

The deformations and stresses of a rotating cylindrical hollow disk made of incompressible functionally-graded hyper-elastic material are theoretically analyzed based on the finite elasticity theory.The hyper-elastic material is described by a new micro-macro transition model.Specially,the material shear modulus and density are assumed to be a function with a power law form through the radial direction,while the material inhomogeneity is thus reflected on the power index m.The integral forms of the stretches and stress components are obtained.With the obtained complicated integral forms,the composite trapezoidal rule is utilized to derive the analytical solutions,and the explicit solutions for both the stretches and the stress components are numerically obtained.By comparing the results with two classic models,the superiority of the model in our work is demonstrated.Then,the distributions of the stretches and normalized stress components are discussed in detail under the effects of m.The results indicate that the material inhomogeneity and the rotating angular velocity have significant effects on the distributions of the normalized radial and hoop stress components and the stretches.We believe that by appropriately choosing the material inhomogeneity and configuration parameters,the functionally-graded material(FGM)hyper-elastic hollow cylindrical disk can be designed to meet some unique requirements in the application fields,e.g.,soft robotics,medical devices,and conventional aerospace and mechanical industries.

关键词： functionally-graded material(FGM) incompressible hyper-elastic model rotating hollow cylindrical disk

Coastal erosion risk assessment of Hainan Island, China

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Acta Oceanologica Sinica 2023年第7期42卷 79-90页

作者： Qianxin Su zhiqiang li Gaocong li Daoheng Zhu Pengpeng Hu College of Electronics and Information Engineering Guangdong Ocean UniversityZhanjiang 524088China

Coastal erosion on islands is increasing due to sea level rise,frequent extreme events,and anthropogenic activities.However,studies on the multifactorial coastal erosion risk and the vulnerability of islands are limited.In this study,the Coastal Erosion Risk Assessment(CERA)method was applied for the first time to the study area in China to assess the erosion risk on the coast of Hainan Island;to explore the effects of coastal ocean dynamics,sediment movement characteristics,and anthropogenic construction;and to discuss the suitability of the method and countermeasures for coastal protection.The results show that the coast of Hainan Island shows high sensitivity,high value,low exposure,and moderate erosion.The whole island showed high vulnerability but low erosion risk,with the eastern region being more affected by erosion,particularly the eastern side of Wulong Port and Yalin Bay in Wenchang,and the shore section of Yalong Bay in Sanya,having a very high risk of coastal erosion.In addition,Monte Carlo simulation was used to check the applicability of the CERA method,and it was found that the rate of shoreline change,population density,and number of storms significantly contributed to coastal erosion,but only the short-term effects of sea level rise were considered.The effects of sea level rise and sediment grain size were primarily analyzed as influencing factors.The effects of sea level rise continue to strengthen,with coastal retreat expected to be greater than 2 m by the mid-21st century.Moreover,Hainan Island is primarily composed of the fine and medium sand types,which have little resistance to coastal erosion.Currently,the impact of sediment grain size is rarely considered in coastal erosion risk assessment studies.However,it can be incorporated into the indicator system in the future,and the spatial variation of indicators can be fully considered to strengthen the refinement study.

关键词： coastal erosion Coastal Erosion Risk Assessment(CERA) vulnerability risk influence factor

Applications of EMD to analyses of high-frequency beachface responses to Storm Bebinca in the Qing’an Bay,Guangdong Province,China

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Acta Oceanologica Sinica 2022年第5期41卷 147-162页

作者： Taihuan Hu zhiqiang li Chunhua Zeng Gaocong li Huiling Zhang College of Electronic and Information Engineering Guangdong Ocean UniversityZhanjiang524088China South China Sea Resources Big Data Center Southern Marine Science and Engineering Guangdong Laboratory(Zhanjiang)Zhanjiang524000China College of Ocean Engineering Guangdong Ocean UniversityZhanjiang524088China

On average,five to six storms occur in the Qiongzhou Strait every year,causing significant damage to coastal geomorphology and several property losses.Tropical Storm Bebinca is the most unusual and complex storm event that has occurred in this region over the last 10 years.To detect the high-frequency beachface responses to the storm,a pressure sensor was deployed in the surf zone to record the free sea surface height,and the heights of grid pile points on the beachface were measured manually to determine beach elevation changes during this storm.Empirical Mode Decomposition and related analysis techniques were used to analyze the high-frequency topography and wave data.The results showed that:(1)the beachface response process occurred in three stages.The first stage was the rapid response stage,wherein the spring tide berm began to erode significantly,and the front edge of the beach berm reacted closely.The two beach sections resisted the harmful energy of the main storm.In the second stage,the beach slope increased after a large sediment loss on the beach berm and its front edge.To adapt to the storm energy,the beach at the low tide line began to erode,and the beach slope decreased.In the third stage,after the storm turned,the wave energy was significantly attenuated,and the beach berm eroded to resist the residual wave energy.The beachface began to oscillate and recover.(2)The main wave surface was the superimposed product of a few internal mode functions.Similar results were observed in beachface changes.High-frequency driving factors determine the local characteristics of beach evolution,and low-frequency driving factors determine the beach evolution trend.(3)The response of sediment to the storm was not a single sea-transportation,but a single-or two-way conversion driven by factors such as wave energy,swash flow,and secondary wave breaking.(4)TheΩ-RTR model is not completely applicable to beach states that undergo rapid changes during storms.Therefore,it is necessary to carry out further research on beach

关键词： EMD internal mode functions Bebinca beach response wave energy beach state

The mechanism of inward and outward expansion of multiscale dynamic permeability of coalbed methane at different temperatures

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Deep Underground Science and Engineering 2023年第1期2卷 88-101页

作者： zhiqiang li Xiaoqiang Hao Yanwei liu lin li MOE Engineering Center of Mine Disaster Prevention and Rescue Henan Polytechnic UniversityJiaozuoChina Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization Henan Polytechnic UniversityJiaozuoChina Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region(Henan Province) Henan Polytechnic UniversityJiaozuoChina Henan Provincial Key Lab of Gas Geology and Control‐Cultivation Base of Provincial and Ministry Joint State Key Henan Polytechnic UniversityJiaozuoChina

The multiscale micro-nano pores in coal can result in the ultra-low permeability of coal,which restricts the efficiency of gas extraction.It is difficult for the conventional seepage-enhancement measures to affect the nanoscale pores within the coal matrix.Thermal stimulation can reach deep into the micro-nano pores within coal matrix to improve the permeability.Therefore,it is important to study the diffusivity and permeability of the multiscale micro-nano pores at different temperatures.In this study,the experiments of diffusion-seepage measured by the methods of GRI(Gas Research Institution)and steady-state were conducted using a cylindrical coal at different temperatures and pressures.The experimental results show that the apparent diffusion coefficient of cylindrical coal is not constant but variable dynamically;and the classical diffusion model fails to describe the full-time process of gas flow accurately.On this basis,a model of multiscale dynamic apparent diffusion-seepage that can accurately describe the full-time flow process was proposed.As is observed,the apparent permeability attenuates dynamically with time without stress loading,and the initial apparent permeability and the attenuation coefficient increase monotonically with the rise of temperature.Under the stress constraint,the steady-state permeability increases after a decrease as the temperature rises,displaying a“U-shaped”pattern.Without stress constraint,the increasing temperature causes the exterior multiscale pores to expand outward by different degrees so as to increase permeability,while the interior micro-nano pores show three inward and outward expansion mechanisms.Under stress constraint,at low temperature and high effective stress,the increasing temperature causes pores to expand inward and the permeability decreases accordingly.When temperature continues to increase,coal expands outward because the effective stress is counteracted by the thermal stress,leading to an increase in permeability.This study is of significance for thermal

关键词： diffusion dynamic gas permeability seepage temperature

Optimal control for spatial-temporal distributed nonlinear autoregressive with exogenous inputs correlation model of steel rolling reheating furnace: a coordinated time-sharing control approach

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Control Theory and Technology 2023年第2期21卷 190-211页

作者： Qingfeng Bao Sen Zhang Jin Guo zhiqiang li Zhenquan Zhang School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of Knowledge Automation for Industrial Processes Ministry of EducationBeijing 100083China Hesteel Group Company limited Shijiazhuang 050031HebeiChina

Accurate control of slab temperature and heating rate is an important significance to improve product performance and reduce carbon emissions for steel rolling reheating furnace(SRRF).Firstly,a spatial temporal distributed-nonlinear autoregressive with exogenous inputs correlation model(STD-NARXCM)to spatial temporal distributed-autoregressive with exogenous inputs correlation model(STD-ARXCM)in working point is established.Secondly,a new coordinated time-sharing control architecture in different time periods is proposed,which is along the length of the SRRF to improve the control performance.Thirdly,a hybrid control algorithm of expert-fuzzy is proposed to improve the dynamic of the temperature and the heating rate during time period 0 to t_(1).A hybrid control algorithm of expert-fuzzy-PID is proposed to enhance the control accuracy and the heating rate during time period t_(1) to t_(2).A hybrid control algorithm of expert-active disturbance rejection control(ADRC)is proposed to boost the anti-interference and the heating rate during time period t_(2) to t_(3).Finally,the experimental results show that the coordinated time-sharing algorithm can meet the process requirements,the maximum deviation of temperature value is 8-13.5℃.

关键词： Steel rolling reheating furnace Spatial-temporal distribution Coordinated time-sharing control Controller structure in different periods Hybrid control algorithm

Cryo-EM structure of glycoprotein C from Crimean-Congo hemorrhagic fever virus

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Virologica Sinica 2022年第1期37卷 127-137页

作者： Na li Guibo Rao zhiqiang li Jiayi Yin Tingting Chong Kexing Tian Yan Fu Sheng Cao CAS Key Laboratory of Special Pathogens Center for Biosafety Mega-ScienceWuhan Institute of VirologyChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Crimean-Congo hemorrhagic fever virus(CCHFV)is a causative agent of serious hemorrhagic diseases in humans with high mortality rates.CCHFV glycoprotein Gc plays critical roles in mediating virus-host membrane fusion and has been studied extensively as an immunogen.However,the molecular mechanisms involved in membrane fusion and Gc-specific antibody-antigen interactions remain unresolved largely because structural information of this glycoprotein is missing.We designed a trimeric protein including most of the ectodomain region of Gc from the prototype CCHFV strain,Ib Ar10200,which enabled the cryo-electron microscopy structure to be solved at a resolution of 2.8Å.The structure confirms that CCHFV Gc is a class Ⅱ fusion protein.Unexpectedly,structural comparisons with other solved Gc trimers in the postfusion conformation revealed that CCHFV Gc adopted hybrid architectural features of the fusion loops from hantaviruses and domain Ⅲ from phenuiviruses,suggesting a complex evolutionary pathway among these bunyaviruses.Antigenic sites on CCHFV Gc that protective neutralizing antibodies target were mapped onto the CCHFV Gc structure,providing valuable information that improved our understanding of potential neutralization mechanisms of various antibodies.

关键词： Crimean-Congo hemorrhagic Fever virus(CCHFV) Glycoprotein C Fusion protein Bunyavirus

The effect of ergosterol on the allogrooming behavior of termites in response to the entomopathogenic fungus Metarhiziumanisopliae

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Insect Science 2023年第1期30卷 185-196页

作者： Yong Chen Chongwen Zhao Wenhui Zeng Wenjing Wu Shijun Zhang Dandan Zhang zhiqiang li Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationInstitute of ZoologyGuangdong Academy of SciencesGuangzhouChina School of Ecology Sun Yat-sen UniversityGuangzhouChina

Termites have physiological and behavioral immunities that make them highly resistant to pathogen infections,which complicates biocontrol efforts.However,the stimuli that trigger the pathogen-avoidance behaviors of termites are still unclear.Our study shows that workers of Coptotermes formosanus exposed to the conidia of Metarhizium anisopliae exhibited a significantly higher frequency and longer duration of allogrooming behaviors compared with untreated termites.Volatile compounds in the cuticle of control termites and termites previously exposed to a suspension of M.anisopliae conidia were analyzed and compared using a gas chromatography-mass spectrometer(GC-MS).Our results showed that the amount of ergosterol differed between the fungus-exposed and control termites.Choice tests showed that termites significantly preferred to stay on filter paper treated with ergosterol(0.05,0.1,or 1.0 mg/mL)compared with control filter paper.In addition,termites exposed to ergosterol followed by M.anisopliae conidia were allogroomed at a significantly higher frequency and for a longer duration than termites exposed to alcohol(the solvent used with the ergosterol in the ergosterol trials)alone followed by M.anisopliae conidia.These results showed that ergosterol may enhance the allogrooming behavior of termites in the presence of entomopathogenic fungi.

关键词： allogrooming behavior entomopathogenic fungus ergosterol recognition social immunity termite

Advances in the Immunotherapeutic Potential of Isocitrate Dehydrogenase Mutations in Glioma

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Neuroscience Bulletin 2022年第9期38卷 1069-1084页

作者： Feng Tang Zhiyong Pan Yi Wang Tian Lan Mengyue Wang Fengping li Wei Quan Zhenyuan liu Zefen Wang zhiqiang li Brain Glioma Center and Department of Neurosurgery Wuhan University Zhongnan HospitalWuhan430071China Department of Physiology Wuhan University School of Basic Medical SciencesWuhan430071China

Isocitrate dehydrogenase(IDH)is an essential metabolic enzyme in the tricarboxylic acid cycle(TAC).The high mutation frequency of the IDH gene plays a complicated role in gliomas.In addition to affecting gliomas directly,mutations in IDH can also alter their immune microenvironment and can change immune-cell function in direct and indirect ways.IDH mutations mediate immune-cell infiltration and function by modulating immune-checkpoint gene expression and chemokine secretion.In addition,IDH mutation-derived D2-hydroxyglutarate can be absorbed by surrounding immune cells,also affecting their functioning.In this review,we summarize current knowledge about the effects of IDH mutations as well as other gene mutations on the immune microenvironment of gliomas.We also describe recent preclinical and clinical data related to IDH-mutant inhibitors for the treatment of gliomas.Finally,we discuss different types of immunotherapy and the immunotherapeutic potential of IDH mutations in gliomas.

关键词： IDH mutation Tumor immune microenvironment Immunotherapy Glioma

Trichoderma metabolites trigger aggregation behavior in Formosan subterranean termites (Coptotermes formosanus)

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Insect Science 2023年第6期30卷 1759-1772页

作者： Lang Zhang Cong Yi Chengju Du Chao Wen zhiqiang li Yong Chen Xiujun Wen Cai Wang College of Forestry and Landscape Architecture South China Agricultural UniversityGuangzhouChina School of Grassland Science Beijing Forestry UniversityBeijingChina Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationInstitute of ZoologyGuangdong Academy of SciencesGuangzhouChina

Our previous studies have shown that some Trichoderma fungi trigger aggregation behavior in Formosan subterranean termites,Coptotermes formosanus Shiraki.However,the mechanisms underlying the induction of termite aggregation by Trichoderma fungi remain unclear.Here,we found that the aqueous or acetone extract of Trichoderma asperellum Samuels,lieckfeldt&Nirenberg and Trichoderma virens Pers.ex Fries isolated from the gut or cuticle of C.formosanus elicited significant termite aggregation in 2-choice tests.We then screened 9 Trichoderma metabolites(3-acetoxy-2-butanone,phenol,3-ethoxypropionic acid,ethyl 2,4-dioxovalerate,diglycolic acid,d-valine,styrene,3-aminopyridine,and hexyl acetoacetate)that triggered termite aggregation.Among them,phenol(1000μg/mL),3-ethoxypropionic acid(10μg/mL),ethyl 2,4-dioxovalerate(1000μg/mL),and diglycolic acid(1000μg/mL)showed the strongest activities,triggering termite aggregation throughout the 24-h period.As T.asperellum and T.virens produce different metabolites that trigger aggregation behavior in termites,the mechanisms underlying the interaction between subterranean termites and Trichoderma fungi likely vary.Future studies are needed to test whether these chemicals can attract termites and increase bait consumption.

关键词： aggregation behavior insect-fungus interaction semiochemical subter-ranean termite Trichoderma