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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 311-323页

作者： Yanqin LI daohui xiang Guofu GAO Feng JIAO Bo ZHAO School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China

Ultrasonic vibration grinding differs from traditional grinding in terms of its material removal mechanism.The randomness of grain-workpiece interaction in ultrasonic vibration grinding can produce variable chips and impact the surface roughness of workpiece.However,previous studies used iterative method to calculate the unformed chip thickness(UCT),which has low computational efficiency.In this study,a symbolic difference method is proposed to calculate the UCT.The UCT distributions are obtained to describe the stochastic interaction characteristics of ultrasonic grinding process.Meanwhile,the UCT distribution characteristics under different machining parameters are analyzed.Then,a surface roughness prediction model is established based on the UCT distribution.Finally,the correctness of the model is verified by experiments.This study provides a quick and accurate method for predicting surface roughness in longitudinal ultrasonic vibration grinding.

关键词： Ultrasonic vibration grinding Undeformed chip thickness(UCT) Distribution characteristics Surface roughness

Pollution characteristics and source apportionment of heavy metal(loid)s in soil and groundwater of a retired industrial park

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Journal of Environmental Sciences 2024年第9期143卷 23-34页

作者： Zijing xiang Shijin Wu Lizhong Zhu Kun Yang daohui Lin Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control Department of Environmental SciencesZhejiang UniversityHangzhou 310058China Zhejiang Ecological Civilization Academy Anji 313300China

Heavy metal(loid)s(HMs)pollution has become a common and complex problem in industrial parks due to rapid industrialization and urbanization.Here,soil and groundwater were sampled from a retired industrial park to investigate the pollution characteristics of HMs.Results show that Ni,Pb,Cr,Zn,Cd,and Cu were the typical HMs in the soil.Source analysis with the positive matrix factorization model indicates that HMs in the topsoil stemmed from industrial activities,traffic emission,and natural source,and the groundwater HMs originated from industrial activities,groundwater-soil interaction,groundwater-rock interaction,and atmosphere deposition.The sequential extraction of soil HMs reveals that As and Hg were mainly distributed in the residue fraction,while Ni,Pb,Cr,Zn,Cd,and Cu mainly existed in the mobile fraction.Most HMs either in the total concentration or in the bioavailable fraction preferred to retain in soil as indicated by their high soil-water partitioning coefficients(K_(d)),and the K_(d) values were correlated with soil pH,groundwater redox potential,and dissolved oxygen.The relative stable soil-groundwater circumstance and the low active fraction contents limited the vertical migration of soil HMs and their release to groundwater.These findings increase our knowledge about HMs pollution characteristics of traditional industrial parks and provide a protocol for HMs pollution scrutinizing in large zones.

关键词： Heavy metal(loid)s Industrial park Source apportionment Chemical fraction Soil-groundwater partitioning

Ultrasonic constitutive model and its application in ultrasonic vibration-assisted milling Ti3Al intermetallics

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Chinese Journal of Aeronautics 2023年第7期36卷 226-243页

作者： Guofu GAO Zongxia FU Yi WANG Xianrong PAN daohui xiang Bo ZHAO School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China

Ultrasonic vibration-assisted technology is widely utilized in the performance research and manufacturing process of metallic materials owing to its advantages of introducing highfrequency acoustic systems. However, the acoustic plasticity constitutive model and potential mechanism, involving Ti3Al intermetallic compounds, have not yet been clarified. Therefore, the Ultrasonic-K-M hybrid acoustic constitutive model of Ti3Al was established by considering the stress superposition, acoustic thermal softening, acoustic softening and acoustic residual hardening effects according to the dislocation density evolution theory and crystal plasticity theory. Meanwhile, the mechanical behavior of ultrasonic vibration-assisted tension(UVAT) and microstructure of ultrasonic vibration-assisted milling(UVAM) for Ti3Al was investigated. Dislocation density to be overcome from initial deformation to failure of Ti3Al was calculated in UVAT and was verified in UVAM. The results indicated that the Ultrasonic-K-M model showed a good agreement with the experimental data. There was an obviously softening phenomenon after introducing the ultrasonic energy field in the Ti3Al whole deformation region, and the degree of softening was positively correlated with amplitude. Furthermore, the maximum reduction ratio in yield strength of Ti3Al was16 % and the maximum reduction value in ultimate tensile strength was 206.91 MPa. The elongation rose first and then fell as amplitude enlarged, but only as the vibration was applied in the whole deformation region, the elongation was always greater than 14.58 %. In addition, The UVAM process significantly reduced the dislocation density increment to be overcome for Ti3Al material removal by 1.37 times, and promoted dislocation motion and cancellation to make twisted dislocations evolve into parallel dislocations. As the amplitude increased to 4 μm, the depth of the disturbed area of the plastic deformation layer increased by a maximum of 2.5 times.

关键词： Dislocation density Plastic deformation layer Ti3Al intermetallic compounds Ultrasonic-K-M hybrid acoustic constitutive model Ultrasonic vibration-assisted technology

Pre-combustion mercury removal with co-production of hydrogen via coal electrolysis

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Journal of Environmental Sciences 2024年第2期136卷 382-389页

作者： xiang Lyu Runming Tao Tianyu Zhang Chemical and Biomolecular Engineering Department Ohio University165 Stocker CenterAthensOH45701USA Electrification and Energy Infrastructures Division Oak Ridge National LaboratoryOak RidgeTN37831USA Beijing Key Lab for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China

Pre-combustion mercury removal via coal electrolysis was performed and investigated on a bench-scale coal electrolytic cell(CEC)systemically,and factorial design was used to determine the effect of different operating conditions(coal particle size,operating temperature,operating cell voltage,and flow rate of slurry)on the percentage of mercury removal,percentage of ash removal,and dry heating value change.The results showed that the operating cell voltage,as well as the interaction between operating cell voltage and coal particle size,are significant factors in the percentage of mercury removal.There is no significant factor in the percentage of ash removal and the dry heating value change,but the coal could be purified while keeping the dry heating value almost constant after electrolysis.A co-product of hydrogen could be produced during coal electrolysis with 50%lower energy consumption compared with water electrolysis.Meanwhile,a mechanism for mercury removal in coal was proposed.The facts indicate that coal electrolysis is a promising method for precombustion mercury removal.

关键词： Pre-combustion mercury removal Coal electrolysis Ash removal Dry heating value Hydrogen production

Selective type II TRK inhibitors overcome xDFG mutation mediated acquired resistance to the second-generation inhibitors selitrectinib and repotrectinib

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Acta Pharmaceutica Sinica B 2024年第2期14卷 517-532页

作者： Shuang xiang Xiaoyun Lu International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Discovery of Chinese Ministry of Education(MOE) Guangdong Provincial Key Laboratory of New Drug Design and EvaluationGuangzhou City Key Laboratory of Precision Chemical Drug DevelopmentSchool of PharmacyJinan UniversityGuangzhou 510632China

Neurotrophic receptor kinase(NTRK) fusions are actionable oncogenic drivers of multiple pediatric and adult solid tumors,and tropomyosin receptor kinase(TRK) has been considered as an attractive therapeutic target for "pan-cancer" harboring these fusions.Currently,two generations TRK inhibitors have been developed.The representative second-generation inhibitors selitrectinib and repotrectinib were designed to overcome clinic acquired resistance of the first-generation inhibitors larotrectinib or entrectinib resulted from solvent-front and gatekeeper on-target mutations.However,xDFG(TRKAG667C/A/S,homologous TRKCG696C/A/S) and some double mutations still confer resistance to selitrectinib and repotrectinib,and overcoming these resistances represents a major unmet clinical need.In this review,we summarize the acquired resistance mechanism of the first-and second-generation TRK inhibitors,and firstly put forward the emerging selective type Ⅱ TRK inhibitors to overcome xDFG mutations mediated resistance.Additionally,we concluded our perspectives on new challenges and future directions in this field.

关键词： NTRK fusions TRK kinase Clinical resistance xDFG mutations Selective type II inhibitors

Dual-ion carrier storage through Mg^(2+) addition for high-energy and long-life zinc-ion hybrid capacitor

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 179-185页

作者： Junjie Zhang xiang Wu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

Cation additives can efficiently enhance the total electrochemical capabilities of zinc-ion hybrid capacitors (ZHCs).However their energy storage mechanisms in zinc-based systems are still under debate.Herein,we modulate the electrolyte and achieve dual-ion storage by adding magnesium ions.And we assemble several Zn//activated carbon devices with different electrolyte concentrations and investigate their electrochemical reaction dynamic behaviors.The zinc-ion capacitor with Mg^(2+)mixed solution delivers 82 mAh·g^(-1)capacity at 1 A·g^(-1) and maintains 91%of the original capacitance after 10000 cycling.It is superior to the other assembled zinc-ion devices in single-component electrolytes.The finding demonstrates that the double-ion storage mechanism enables the superior rate performance and long cycle lifetime of ZHCs.

关键词： zinc-ion hybrid capacitor MgSO_(4) electrolyte rate performance storage mechanism

Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： xiang Meng Pierre Désesquelles Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great challenges.Spent ion exchange resins have become a focus of attention due to their high production and serious environmental risks.In this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)calculations.The prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the degradation.The meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain reactivity.The C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily broken.It is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring separation.The decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism

Adhesive strength of CVD diamond thin films quantitatively measured by means of the bulge and blister test

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Journal of University of Science and Technology Beijing 2008年第4期15卷 474-479页

作者： daohui xiang Ming Chen Yuping Ma Fanghong Sun School of Mochanical Engineering Shanghai Jiaotong University Shanghai 200240 China School of Mechanical and Power Engineering Henan Polytechnic University Jiaozuo 454000 China

Large advancement has been made in understanding the nucleation and growth of chemical vapor deposition （CVD） diamond, but the adhesion of CVD diamond to substrates is poor and there is no good method for quantitative evaluation of the adhesive strength. The blister test is a potentially powerful tool for characterizing the mechanical properties of diamond films. In this test, pressure was applied on a thin membrane and the out-of-plane deflection of the membrane center was measured. The Young＇s modulus, residual stress, and adhesive strength were simultaneously determined using the load-deflection behavior of a membrane. The free-standing window sample of diamond thin films was fabricated by means of photolithography and anisotropic wet etching. The research indicates that the adhesive strength of diamond thin films is 4.28±0.37 J/m^2. This method uses a simple apparatus, and the fabrication of samples is very easy.

关键词： diamond thin films adhesive strength chemical vapor deposition （CVD） elastic modulus

Potential role of hippocampal neurogenesis in spinal cord injury induced post-trauma depression

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Neural Regeneration Research 2024年第10期19卷 2144-2156页

作者： Ying Ma Yue Qiao xiang Gao Spinal Cord and Brain Injury Research Group Stark Neuroscience Research InstituteIndianapolisINUSA Department of Neurological Surgery Indiana University School of MedicineIndianapolisINUSA Department of Neurology Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

It has been reported both in clinic and rodent models that beyond spinal cord injury directly induced symptoms, such as paralysis, neuropathic pain, bladder/bowel dysfunction, and loss of sexual function, there are a variety of secondary complications, including memory loss, cognitive decline, depression, and Alzheimer's disease. The largescale longitudinal population-based studies indicate that post-trauma depression is highly prevalent in spinal cord injury patients. Yet, few basic studies have been conducted to address the potential molecular mechanisms. One of possible factors underlying the depression is the reduction of adult hippocampal neurogenesis which may come from less physical activity, social isolation, chronic pain, and elevated neuroinflammation after spinal cord injury. However, there is no clear consensus yet. In this review, we will first summarize the alteration of hippocampal neurogenesis post-spinal cord injury. Then, we will discuss possible mechanisms underlie this important spinal cord injury consequence. Finally, we will outline the potential therapeutic options aimed at enhancing hippocampal neurogenesis to ameliorate depression.

关键词： antidepressants chronic pain depression exercise hippocampal neurogenesis inflammation inhibition neuroinflammation physical activity deficits social isolation spinal cord injury

Review of dynamics and active control of large-scale space membrane antenna

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Astrodynamics 2024年第1期8卷 1-26页

作者： xiang Liu Guoping Cai Department of Engineering Mechanics MOE Key Laboratory of HydrodynamicsChongqing Research InstituteShanghai Jiao Tong UniversityShanghai200240China

Large-scale space membrane antennas have significant potential in satellite communication,space-based early warning,and Earth observation.Because of their large size and high flexibility,the dynamic analysis and control of membrane antenna are challenging.To maintain the working performance of the antenna,the pointing and surface accuracies must be strictly maintained.Therefore,the accurate dynamic modeling and effective active control of large-scale space membrane antennas have great theoretical significance and practical value,and have attracted considerable interest in recent years.This paper reviews the dynamics and active control of large-scale space membrane antennas.First,the development and status of large-scale space membrane antennas are summarized.Subsequently,the key problems in the dynamics and active control of large membrane antennas,including the dynamics of wrinkled membranes,large-amplitude nonlinear vibration,nonlinear model reduction,rigid-flexible-thermal coupling dynamic modeling,on-orbit modal parameter identification,active vibration control,and wave-based vibration control,are discussed in detail.Finally,the research outlook and future trends are presented.

关键词： large-scale space membrane antenna dynamicmodeling active control