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Defence Technology（防务技术） 2023年第2期20卷 72-83页

作者： shu-sen yuan Wen-Xiang Deng Jian-Yong Yao Guo-Lai Yang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjingChina

Backlash nonlinearity inevitably exists in the actuator of tank horizontal stabilizer and has adverse effect on the system control performance,however,how to effectively eliminate its effect remains a pending *** solve this problem,a robust adaptive precision motion controller is presented in this paper to address uncertainties and unknown actuator backlash of tank horizontal *** controller handles the modeling uncertainties including parameter uncertainties and unmodeled disturbances by integrating adaptive feedforward compensation and continuous nonlinear robust *** on the backstepping method,a smooth backlash inverse model is constructed by combining the adaptive ***,the unknown backlash parameters of the system can be approximated through the parameter adaptation,and the impact of the actuator backlash nonlinearity is effectively compensated via the inverse operation,which can availably improve the tracking ***,the adaptive law can update the disturbance ranges of tank horizontal stabilizer online in real time,which enhances the feasibility in practical engineering ***,the stability analysis based on Lyapunov function shows that with the existence of unmodeled disturbances and unknown actuator backlash,the designed controller guarantees excellent asymptotic output tracking *** comparative results verify the effectiveness of the proposed control strategy.

关键词： Tank Horizontal stabilizer Adaptive control Robust control Backlash inverse

Studies on organophosphorus compounds ***-reactivity studies of organophosphorus compounds by MNDO calculations

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Chinese Journal of Chemistry 1992年第2期10卷 161-170页

作者： LI,shu-sen yuan,Cheng-Ye Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032 Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032

MNDO and MM2(85)methods were used to study the conformation and the structure- reactivity relationship of neutral and acidic phosphorus *** calculation results indicate that for the most stable conformation,the charge density of phosphoryl oxygen(q_O)is determined not only by the electronegativity of the substituents,but also by the conformation of the alkoxyl groups on the phosphorus ***,the conformation of the alkoxyl group provides,as a rule, more important influence on the charge density of the phosphoryl ***,the energy of the highest occupied molecular orbital(EHOMO)is basically dependent on the eletronegativity of the substituents,while the donating ability or the withdrawing ability of the neutral phosphorus com- pounds is mainly governed by the EHOMO but not the q_*** is also true for other kinds of the neutral oxygen-containing compounds.

关键词： Studies on organophosphorus compounds 52.Structure-reactivity studies of organophosphorus compounds by MNDO calculations

分子内氢键 Ⅳ.稠环芳香螯合剂的内氢键和互变异构

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化学学报 1984年第8期42卷 823-828页

作者：李树森袁承业中国科学院上海有机化学研究所

在芳香族螯合剂分子中,连接两个配位原子化学键的刚性对其螯合能力有重要影响.试比较8-羟基喹啉(1)和2-(2’-羟苯基)吡啶(2),虽然1的内氢键比2弱,且O…N间距也大于2,但1对过渡金属的螯合能力却比2大得多.Freiser据此认为,五员螯合环的... 详细信息

在芳香族螯合剂分子中,连接两个配位原子化学键的刚性对其螯合能力有重要影响.试比较8-羟基喹啉(1)和2-(2’-羟苯基)吡啶(2),虽然1的内氢键比2弱,且O…N间距也大于2,但1对过渡金属的螯合能力却比2大得多.Freiser据此认为,五员螯合环的过渡金属配合物比六员环稳定.为进一步考察这类结构效应,我们合成了稠环螯合剂3～5,并与类似物6～8及1和2一起,从分子内氢键及螯合环中各键的刚性对Li的萃取性能的影响来观察这些化合物配位能力的变化.

关键词：氢键化学键分子内互变异构异构现象鳌合剂酮式配位原子配位体稠环

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分子内氢键 Ⅰ.分子内氢键的PMO研究

化学学报 1982年第2期 97-109页

作者：李树森袁承业中国科学院上海有机化学研究所

脂肪族化合物的分子内氢键与分子间氢键无论在性质和强度上都没有明显的区别,而在共轭体系中的分子内氢键强度却可成倍地大于类似官能团间的分子间氢键,这为应用PMO方法来研究含杂交替烃体系中的分子内氢键提供了可能性.观察到如下规律... 详细信息

脂肪族化合物的分子内氢键与分子间氢键无论在性质和强度上都没有明显的区别,而在共轭体系中的分子内氢键强度却可成倍地大于类似官能团间的分子间氢键,这为应用PMO方法来研究含杂交替烃体系中的分子内氢键提供了可能性.观察到如下规律:对于相同官能团的一系列化合物,分子内氢键的强度主要决定于给予原子上的电荷密度,电荷密度越大,内氢键越强;在非键分子轨道系数相同的情况下,共轭体系越大,内氢键越强.当分子中有脂并环取代基时不服从上述规律.这种脂并环取代基有时会增强内氢键的强度.

关键词：氢键化合物化学键分子内氢键强度电荷密度电性共轭体系 PMO

Co/Co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang Chen Yongyue Zhuang Yanxin Qiao Yu Zhang Aihua yuan Hu Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NCS)decorated with dual-phase Co/Co_(7)Fe_(3)heterojunctions(CoFe@NCS).The phase composition of materials has been adjusted by controlling the alloying *** optimal CoFe_(0.08)@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co_(7)Fe_(3)alloy and metallic Co *** the CoFe_(0.08)@NCS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/C+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

The dopaminergic system and Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2495-2512页

作者： Yuhan Zhang yuan Liang Yixue Gu International Medical College Chongqing Medical UniversityChongqingChina College of Pharmacy Chongqing Medical UniversityChongqingChina Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of NeurologyChongqingChina

Alzheimer's disease is a common neurodegenerative disorder in older *** its prevalence,its pathogenesis remains unclea *** addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this *** is a crucial catecholaminergic neurotransmitter in the human ***-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical *** r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive *** review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related *** aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

关键词： adverse drug reaction Alzheimer's disease catecholamine dopamine receptor dopamine receptor heterodimers dopaminergic system neurodegenerative disease neurotransmitter signaling pathways traditional Chinese medicine treatment

Nano-SiC_P particles distribution and mechanical properties of Al-matrix composites prepared by stir casting and ultrasonic treatment

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China Foundry 2018年第3期15卷 203-209页

作者： shu-sen Wu Du yuan shu-lin Lü Kun Hu Ping An State Key Lab of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology

Nano-ceramic particles are generally difficult to add into molten metal because of poor wettability. Nano-SiC particles reinforced A356 aluminum alloy composites were prepared by a new complex process, i.e., a molten-metal process combined with high energy ball milling and ultrasonic vibration methods. The nano particles were β-SiCp with an average diameter of 40 nm, and pre-oxidized at about 850 ℃ to form an oxide layer with a thickness of approximately 3 nm. The mm-sized composite granules containing nano-SiCp were firstly produced by milling the mixture of oxidized nano-SiCp and pure Al powders, and then were remelted in the matrix-metal melt with mechanical stirring and treated by ultrasonic vibration to prepare the composite. SEM analysis results show that the nano-SiC particles are distributed uniformly in the matrix and no serious agglomeration is observed. The tensile strength and elongation of the composite with 2wt.% nano-SiCp in as-cast state are 226 MPa and 5.5％, improved by 20％ and 44％, respectively, compared with the A356 alloy.

关键词： metal matrix composites SiC nanopaticles A356 aluminum alloy solid-liquid mixed casting ultrasonic vibration

Sex differences in aging and injured brain

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Neural Regeneration Research 2025年第10期20卷 2901-2902页

作者： Jordan N.Williamson yuan Yang University of Illinois Urbana-Champaign Grainger College of EngineeringDepartment of BioengineeringUrbanaILUSA Carle Foundation Hospital Stephenson Family Clinical Research InstituteClinical Imaging Research CenterUrbanaILUSA University of Illinois Urbana-Champaign Beckman Institute for Advanced Science and TechnologyUrbanaILUSA Northwestern University Department of Physical Therapy and Human Movement SciencesChicagoILUSA

Background:The prevalence,age of onset,and symptomatology of traumatic brain injury,stroke,and neurodegenerative diseases(such as Alzheimer’s disease(AD),Parkinson’s disease,amyotrophic lateral sclerosis,and Huntington’s disease)differ substantially between males and *** higher prevalence of these brain disorders has been attributed to females having a greater longevity compared with *** one of the greatest risk factors of acquired brain injury(such as stroke,traumatic brain injury caused by fall)and neurodegenerative disease is age.

关键词： Huntington prevalence traumatic

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

Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： Yifan Miao Li Zhao Yajun Zhang Zhe yuan Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and Quantum Computing Fudan University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

关键词： neuromorphic computing spintronics magnetic tunnel junction neural networks