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Journal of Systems Engineering and Electronics 2023年第3期34卷 804-814页

作者： CAO Hui duan Fuhai duan yu’nan School of Mechanical Engineering Dalian University of TechnologyDalian 116024China

The reliability-based selective maintenance(RSM)decision problem of systems with components that have multiple dependent performance characteristics(PCs)reflecting degradation states is addressed in this paper.A vine-Copulabased reliability evaluation method is proposed to estimate the reliability of system components with multiple ***,the marginal degradation reliability of each PC is built by using the Wiener stochastic process based on the PC’s degradation *** joint degradation reliability of the component with multiple PCs is established by connecting the marginal reliability of PCs using *** addition,two RSM decision models are developed to ensure the system accomplishes the next *** genetic algorithm(GA)is used to solve the constraint optimization problem of the models.A numerical example illustrates the application of the proposed RSM method.

关键词： D-vine genetic algorithm(GA) reliability-based selective maintenance(RSM) redundant system Wiener stochastic process

Preparation and applications of calcium ferrite as a functional material:A review

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 292-310页

作者： Xiuli Han Bowen duan Lei Liu Shilong Fang Weiwei Wang College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources of Hebei Province Tangshan 063210China Key Laboratory of Mining Development and Security Technology of Hebei Province Tangshan 063210China

Calcium ferrite(CF)is recognized as a potential green and efficient functional material because of its advantages of magnetism,electrochemistry,catalysis,and biocompatibility in the fields of materials chemistry,environmental engineering,and ***-fore,the obtained research results need to be systematically summarized,and new perspectives on CF and its composite materials need to be *** on the presented studies of CF and its composite materials,the types and structures of the crystal are *** addition,the current application technologies and theoretical mechanisms with various properties in different fields are ***,the various preparation methods of CF and its composite materials are elaborated in *** importantly,the advantages and disadvantages of the synthesis methods of CF and its composite materials are discussed,and the existing problems and emerging challenges in practical production are ***,the key future research directions of CF and its composite materials have been prospected from the potential application technologies to provide references for its synthesis and efficient utilization.

关键词： calcium ferrite mineral functional materials preparation application perspectives

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星形AB共聚物和A均聚物的共组装模拟研究

原子与分子物理学报 2025年第5期42卷 90-94页

作者：段润宇新疆大学物理科学与技术学院乌鲁木齐830017

具有独特结构的纳米粒子在高分子材料领域具有广泛的应用.本文采用耗散粒子动力学模型系统的研究了三臂星形AB二嵌段共聚物和A均聚物共混体系的共组装相行为.通过调节聚集体中星形共聚物浓度和AB嵌段的长度比有效地控制了AB/A共混体系... 详细信息

具有独特结构的纳米粒子在高分子材料领域具有广泛的应用.本文采用耗散粒子动力学模型系统的研究了三臂星形AB二嵌段共聚物和A均聚物共混体系的共组装相行为.通过调节聚集体中星形共聚物浓度和AB嵌段的长度比有效地控制了AB/A共混体系中聚集体的共组装形貌.预测了一些有趣的结构,比如,具有较厚壳层的核-壳-补丁结构、具有壳层的且中心凹陷的圆盘状结构以及不规则椭球的多室结构.本文还发现对于具有较长A嵌段的星形链,增大A均聚物在聚集体中的浓度能够消除聚集体内B嵌段形成的核;对于具有较短A嵌段的星形链,少量的A均聚物能够诱导聚集体共组装成具有长条状核的多室纳米粒子.

关键词：耗散粒子动力学星形二嵌段共聚物共组装纳米粒子

Theoretical elastoplastic analysis for foundations with geosynthetic-encased columns

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第7期13卷 506-518页

作者： yuan-yu duan Yi-ping ZHANG Dave CHAN Ya-nan yu College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaCanada

As a new technique in ground improvement, geosynthetic-encased columns (GECs) have promising applications in soft soil foundation. By assuming yielding occurs in the columns while the surrounding soil and the geosynthetic remain elastic, an elastoplastic analytical procedure for foundations improved by GECs is proposed. The radial stresses that the geosynthetic provides and the elastoplastic deformations of the foundation resting on a rigid base are derived. A comparison with finite element analysis shows that the proposed method is effective and can provide a reasonable prediction of a GEC's deformation. Subsequent parametric analysis indicates that higher geosynthetic stiffness leads to better performance of the composite foundation. The optimum length of encasement is related to the load acting on the foundation and the permissible vertical and radial displacements of the column. Moreover, as the dilation angle of the column increases, the settlement decreases, especially under high loading. The influence of the encasement is more significant in soils with smaller elastic modulus.

关键词： Geosynthetic-encased columns (GECs) Equal vertical strain Elastoplastic deformation Analytical procedure

Double dehydrogenation of carbocyclic β-dicarbonyl compounds:Koser's reagent can do what iodine(V) reagents can

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Science China Chemistry 2019年第5期62卷 597-601页

作者： Shan-Shan Liu Li Wang Ya-nan duan Ao yu Chi Zhang State Key Laboratory of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)College of ChemistryNankai University Department of Chemical Engineering and Safety Binzhou University Central Laboratory College of ChemistryNankai University

Koser's reagent is found to be effective in the oxidative double dehydrogenation of various carbocyclic β-dicarbonyl compounds,which constitutes the first example on dehydrogenation reactivity of hypervalent iodine(Ⅲ) reagents for carbocyclic carbonyl compounds. DFT calculations reveal that the rate-determining step is the electrophilic addition of PhI+OH onto enolate of monodehydrogenated product.

关键词： Koser’s reagent double dehydrogenation hypervalent twisting 2,3-benzotropone DFT calculations

Au/TS-1 catalyst for propylene epoxidation with H_(2)and O_(2):Effect of surface property and morphology of TS-1 zeolite

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nano Research 2023年第5期16卷 6278-6289页

作者： Jialun Xu Zhihua Zhang Daiyi yu Wei Du nan Song Xuezhi duan Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

The catalytic performances over propylene epoxidation with H_(2)and O_(2)(HOPO process)are significantly affected by the properties(e.g.,surface properties,Ti coordination,morphology)of titanosilicate *** urea into zeolite synthesis is a simple and convenient method to modify these properties of titanosilicate *** pore-blocked titanium silicalite-1(TS-1,i.e.,TS-1-B)with the lower urea dosage possesses more defective structure and unsaturated coordinated Ti sites verified by 29Si nuclear magnetic resonance(NMR)and X-ray photoelectron spectroscopy(XPS)analysis,which results in a high initial activity and hydrogen efficiency;while the high surface acidity generated by these Ti species leads to a continuous decrease in the activity and the propylene oxide(PO)selectivity during the *** the amount of urea gradually increases,the TS-1-B samples present the reduced surface defects and defective and unsaturated Ti ***,TS-1-B-0.30U presents the weaker PO adsorption on PO-diffusion reflectance infrared Fourier transform spectra(DRIFTS),thus results in the high stable PO formation rate and selectivity over its Au ***,a flat-plate-like shape with a shorter thickness of 100 nm along the b-axis direction is observed on the urea-modified *** with the conventional ellipsoidal TS-1 with crystal sizes of 200 and 500 nm,the flat-plate-like TS-1-0.30U displays the less surface defects,unsaturated Ti species,the weaker Lewis acid,which is favorable for the desorption and intracrystalline diffusion of PO,thus reduces the occurrence of side reactions for the improved selectivity and *** work may provide a reference for developing titanium-containing materials with high activity and stability over HOPO reaction.

关键词： propylene epoxidation titanium silicalite-1(TS-1) surface properties Ti species morphological regulation diffusion

Peripheral mitochondrial DNA as a neuroinflammatory biomarker for major depressive disorder

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Neural Regeneration Research 2025年第6期20卷 1541-1554页

作者： Jinmei Ye Cong duan Jiaxin Han Jinrong Chen Ning Sun yuan Li Tifei yuan Daihui Peng Division of Mood Disorder Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Shanghai Key Laboratory of Psychotic Disorders Brain Health InstituteNational Center for Mental DisordersShanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina

In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. Herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder.

关键词： biomarker cytokine exosomes inflammasome major depressive disorder microglia mitochondrial DNA mitochondrial dysfunction neuroinflammation Toll-like receptor

Model checking concurrent systems with MSVL

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Science China(Information Sciences) 2016年第11期59卷 224-226页

作者： nan ZHANG Zhenhua duan Cong TIAN Institute of Computing Theory and Technology Xidian University

Model checking,proposed by Clarke and Emerson[1]as well as Queille and Sifakis[2],is an automatic verification approach for hardware and software ***,as Clarke pointed out[3],model checking suffers from(1)the state explosion problem,which is typically caused by models growing exponentially in the number of parallel components or data elements of an argument system;(2)different notations used to model a system and required properties;(3)the expressive

关键词： Model checking concurrent systems with MSVL VHDL Figure MSV

Structural design and model fabrication of cable-rib tensioned deployable parabolic cylindrical antenna

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Chinese Journal of Aeronautics 2023年第8期36卷 229-246页

作者： Shunji ZHANG Baoyan duan Shuxin ZHANG nan WANG Shaanxi Key Laboratory of Space Solar Power Station System Xi’an 710071China School of Electromechanical Engineering Xidian UniversityXi’an 710071China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100101 China

Deployable mechanisms with light weight and high storage ratio have received considerable attention for space applications. To meet the requirements of space missions, a parabolic cylindrical deployable antenna based on cable-rib tension structures is proposed and verified by a physical prototype. The parabolic cylindrical antenna adopts simple parallel four-bar mechanisms to construct the basic deployable unit, and the cylindrical direction dimension can be easily extended by modularization, which has obvious advantages in storage ratio and area density. Considering the complexity of the entire antenna structure design, including cable networks and flexible trusses, the form-finding design optimization model of a parabolic cylindrical antenna is established using the force density sensitivity method, and then the kinematics analysis of the deployable mechanism is carried out. Finally, a single-module prototype with a deployable diameter of 4 m × 2 m was designed and fabricated. The results of the ground deployment process test and surface accuracy measurements show that the antenna has good feasibility and practicability.

关键词： Form-finding design Kinematic analysis Mechanism design Paraboliccylindrical antenna Principle prototype

Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex

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Neural Regeneration Research 2025年第10期20卷 2923-2937页

作者： Yan Li Peng Hao Hongmei duan Fei Hao Wen Zhao yudan Gao Zhaoyang Yang Kwok-Fai So Xiaoguang Li Department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina China Rehabilitation Science Institute China Rehabilitation Research CenterBeijing Key Laboratory of Neural Injury and RehabilitationBeijingChina Center of Neural Injury and Repair Beijing Institute for Brain DisordersBeijingChina Beijing Key Laboratory for Biomaterials and Neural Regeneration School of Engineering MedicineBeihang UniversityBeijingChina Guangdong-HongKong-Macao Institute of CNS Regeneration Ministry of Education CNS Regeneration Collaborative Joint LaboratoryJinan UniversityGuangzhouGuangdong ProvinceChina Bioland Laboratory(Guangzhou Regenerative Medicine and Health Guangdong Laboratory) GuangzhouGuangdong ProvinceChina Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences The University of Hong KongHong Kong Special Administration RegionChina Center for Brain Science and Brain-Inspired Intelligence Guangdong-HongKong-Macao Greater Bay AreaGuangzhouGuangdong ProvinceChina Co-innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina

The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after ***,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains *** this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic *** findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated ***,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain *** findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.

关键词： adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation