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AM1 and ab initio studies on the internal reorganization energy of self-exchange electron transfer reactions of several quinone derivatives

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Chinese Science Bulletin 2001年第15期46卷 1242-1251页

作者： Shuhua Ma Xiaodong zhang Hong Xu Xingkang zhang Qiyuan zhang State Key Laboratory for Structural Chemistry of Unstable & Stable Species Center of Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing China

The semiempirical AMI method, ah initio (HF/3-21G, 6-31G, 6-31G(d), 6-31+G(d)) and DFT (B3LYP/6-31G(d), 6-31+G(d)) methods were used to optimize the geometry of DDQ and its anion radical DDQ-. Nelsen’s model was used to calculate the internal reorganization energy λi of self-exchange electron transfer (ET) reactions. The calculated λi results of DDQ/DDQ-. by AM1 and B3LYP/ 6-31G(d), 6-31+G(d) methods are close to each other and consistent with the reported values; while those from Har-tree-Fock methods are too large because of not consideringthe effect of electron correlation. The structure and ET behavior of MQ0 /MQ0- couple were studied by AM1 and DFT (B3LYP/6-31G(d), 6-31+ G(d, p)) methods, and those of MQ0 /MQn-(n=1-7) were studied by AM1 method for the first time. The results indicate that the values of the heat of formation of MQn increases with the increasing of the length of the isoamylene substituent chains. It also shows that the length of substituent has little effect on the bond lengths,

关键词： DDQ menaquinone (MQn) self-exchange electron transfer internal reorganization energy AM1 ab initio DFT.

Test Study on Current Force on Mooring Ships

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China Ocean Engineering 1993年第2期8卷 225-242页

作者： zhang, Furan Zhao, Jun zhang, Xueqin Tianjin Research Inst of Water Transport Engineering Tianjin China

In respect of an offshore berthing pillar, the test study result of current force acting on mooring ships is described in this paper. Empirical and semi-empirical relationships of current force coefficient are given according to the angle between the flow direction and the ship's longitudinal axis, which are coincident with the result of theoretical analysis.

关键词： Flow of water Loads (forces) Mathematical models Numerical methods Ocean currents Ship models Ships

Deep transfer network of heterogeneous domain feature in machine translation

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High-Confidence Computing 2022年第4期2卷 8-13页

作者： Yupeng Liu Yanan zhang Xiaochen zhang Harbin University of Science and Technology Harbin 150080China Heilongjiang Institute of Technology Harbin 150050China

In order to address the shortcoming of feature representation limitation in machine translation(MT)system,this paper presents a feature transfer method in *** feature transfer of the decoding process considered not only their own translation system,but also transferred knowledge of another translation *** domain meta feature and the objective function of domain adaptation are used to better model the domain transfer *** this paper,extensive experiments and comparisons are *** experiment results show that the proposed model has a significant improvement in domain transfer *** first model has better performance than baseline system,which improves 3.06 BLEU score on the news test set,improves 3.27 BLEU score on the education test set,and improves 3.93 BLEU score on the law test set;The second model improves 3.16 BLEU score on the news test set,improves 3.54 BLEU score on the education test set,and improves 4.2 BLEU score on the law test set.

关键词： Neural translation model Deep transfer network Heterogeneous domain Meta feature

Unified Explanation of Quark-Lepton Mass Spectra in q-Deformed Quantum Mechanics

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Chinese Physics Letters 2000年第2期17卷 91-93页

作者： zhang Jian-Zu School of Science East China University of Science and TechnologyShanghai 200237

The quark-lepton mass spectra in q-deformed quantum mechanics are investigated. The theoretical formula of the spectrum includes two new quantum numbers: the q-exciting number n describing generations and the scaling indexes Mi describing families. This formula shows two exponential increases in the mass distribution as generation n increases, the intervals of masses in a given family exponentially increase, and the mass splittings among different members in a generation also exponentially increase. The theoretical values of masses of quarks and leptons reasonably agree with the experimental data except for the electron mass which is one order larger.

关键词： quark exponentially quantum

Deep Reinforcement Learning Based Joint Partial Computation Offloading and Resource Allocation in Mobility-Aware MEC System

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China Communications 2022年第8期19卷 85-99页

作者： Luyao Wang Guanglin zhang College of Information Science and Technology Donghua UniversityShanghai 201620China Engineering Research Center of Digitized Textile and Apparel Technology Ministry of EducationShanghai 201620China

Mobile edge computing(MEC)emerges as a paradigm to free mobile devices(MDs)from increasingly dense computing workloads in 6G *** quality of computing experience can be greatly improved by offloading computing tasks from MDs to MEC *** energy harvested by energy harvesting equipments(EHQs)is considered as a promising power supply for users to process and offload *** this paper,we apply the uniform mobility model of MDs to derive a more realistic wireless channel model in a multi-user MEC system with batteries as EHQs to harvest and storage *** investigate an optimization problem of the weighted sum of delay cost and energy cost of MDs in the MEC *** propose an effective joint partial computation offloading and resource allocation(CORA)algorithm which is based on deep reinforcement learning(DRL)to obtain the optimal scheduling without prior knowledge of task arrival,renewable energy arrival as well as channel *** simulation results verify the efficiency of the proposed algorithm,which undoubtedly minimizes the cost of MDs compared with other benchmarks.

关键词： mobile edge computing energy harvesting device-mobility partial computation offloading resource allocation deep reinforcement learning

Magma Evolution Processes in the Southern Okinawa Trough:Insights from Melt Inclusions

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Journal of Ocean University of China 2021年第6期20卷 1383-1397页

作者： zhang Yujiao ZHAI Shikui Key Laboratory of Submarine Geosciences and Prospection of Ministry of Education Ocean University of ChinaQingdao 266100China

The Okinawa Trough is an initial back-arc basin that is influenced by the subduction of the Philippine Sea Plate and develops on the continental *** Okinawa Trough is a natural laboratory for the study of basin evolution,magmatism,and crustmantle processes in the early stage of back-arc *** inclusions are small droplets of magma that are captured during the mineral crystallization process and can record the geochemical composition changes during magma *** this study,the geochemical compositions of melt inclusions in host plagioclases of two volcanic rock samples at Station nos.9-1 and 9-2 from the southern Okinawa Trough are systematically *** on previous studies,the origin and evolution of magma and the introduction of subducting materials in the study area are *** show that melt inclusions are characterized by the relative enrichment of large-ion lithophile elements,depletion of high-field-strength elements,and slight enrichment of rare earth ***,the subduction of the Philippine Sea Plate introduced sediment-derived melts and fluids into the magma source area of the southern Okinawa ***,4%to 5%partial melting of the hydrated mantle produces basaltic *** melt inclusions of andesite and dacite investigated in this study were formed by fractional crystallization of basaltic ***,the crystallization of plagioclase,pyroxene,and magnetite occurred during the late stage of magma *** temperature-pressure data show that the melt inclusions in plagioclase have two capture periods:one is at temperatures above 1250℃and the other is at temperatures between 1180℃and 1200℃.The capture pressure of the inclusions at temperatures between 1180℃and 1200℃is between 5.6 kPa and 6.1 kPa,corresponding to the depth of 15–17 km below the *** geochemical characteristics of major and trace elements in inclusions show that the samples from two stations(i.e.,9-1 and 9-2)have similar

关键词： melt inclusions magma evolution processes contamination of crustal materials introduction of subducting materials the southern Okinawa Trough

Fractional Fourier transform on R^(2)and an application

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Frontiers of Mathematics in China 2022年第6期17卷 1181-1200页

作者： Yue zhang Wenjuan LI School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710072China

We focus on the L^(p)(R^(2))theory of the fractional Fourier transform(FRFT)for 1≤p≤*** L^(1)(R^(2)),we mainly study the properties of the FRFT via introducing the two-parameter chirp *** order to get the pointwise convergence for the inverse FRFT,we introduce the fractional convolution and establish the corresponding approximate *** the well-defined inverse FRFT is given via approximation by suitable means,such as fractional Gauss means and Able ***,if the signal F_(α,β)f is received,we give the process of recovering the original signal f with *** L^(2)(R^(2)),the general Plancherel theorem,direct sum decomposition,and the general Heisenberg inequality for the FRFT are obtained.

关键词： Fractional Fourier transform(FRFT) inverse fractional Fourier transform signal recovery direct sum decomposition general Heisenberg inequality

State observers of quasi-reversible discrete-time switched linear systems

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Control Theory and Technology 2023年第3期21卷 390-396页

作者： Zhendong Sun Qiang zhang College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

This work addresses observer design for the general class of quasi-reversible discrete-time switched linear *** the mild assumption that the switched system is observable,we present constructive approaches to design state observers to estimate the *** types of observers are designed:one is with full order and the other is with reduced order,both could reconstruct the system state in finite times.A numerical example is presented to illustrate the effectiveness of the proposed approaches.

关键词： Switched linear systems Observer-Observability

The role of natural flavonoids on neuroinflammation as a therapeutic target for Alzheimer's disease:a narrative review

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Neural Regeneration Research 2023年第12期18卷 2582-2591页

作者： Qian zhang Yaping Yan National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China Key Laboratory of Medicinal Resources and Natural Pharmaceutical ChemistryThe Ministry of EducationCollege of Life SciencesShaanxi Normal UniversityXi’anShaanxi ProvinceChina

Alzheimer's disease is a neurodegenerative disease that affects a large proportion of older adult people and is characterized by memory loss,progressive cognitive impairment,and various behavioral *** the pathological mechanisms underlying Alzheimer's disease are complex and remain unclear,previous research has identified two widely accepted pathological characteristics:extracellular neuritic plaques containing amyloid beta peptide,and intracellular neurofibrillary tangles containing ***,research has revealed the significant role played by neuroinflammation over recent *** inflammatory microenvironment mainly consists of microglia,astrocytes,the complement system,chemokines,cytokines,and reactive oxygen intermediates;collectively,these factors can promote the pathological process and aggravate the severity of Alzheimer's ***,the development of new drugs that can target neuroinflammation will be a significant step forward for the treatment of Alzheimer's *** are plant-derived secondary metabolites that possess various *** research found that multiple natural flavonoids could exert satisfactory treatment effects on the neuroinflammation associated with Alzheimer's *** this review,we describe the pathogenesis and neuroinflammatory processes of Alzheimer's disease,and summarize the effects and mechanisms of 13 natural flavonoids(apigenin,luteolin,naringenin,quercetin,morin,kaempferol,fisetin,isoquercitrin,astragalin,rutin,icariin,mangiferin,and anthocyanin)derived from plants or medicinal herbs on neuroinflammation in Alzheimer's *** an important resource for the development of novel compounds for the treatment of critical diseases,it is essential that we focus on the exploitation of natural *** particular,it is vital that we investigate the effects of flavonoids on the neuroinflammation associated with Alzheimer's disease in greater detail.

关键词： Alzheimer's disease astrocytes flavonoids microglia natural products neuroinflammation