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High-Precision Doppler Frequency Estimation Based Positioning Using OTFS Modulations by Red and Blue Frequency Shift Discriminator

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China Communications 2024年第2期21卷 17-31页

作者： Shaojing Wang Xiaomei Tang Jing Lei Chunjiang Ma chao wen Guangfu Sun School of Electronic Science National University of Defense TechnologyChangsha 410073China

Orthogonal Time Frequency and Space(OTFS) modulation is expected to provide high-speed and ultra-reliable communications for emerging mobile applications, including low-orbit satellite communications. Using the Doppler frequency for positioning is a promising research direction on communication and navigation integration. To tackle the high Doppler frequency and low signal-to-noise ratio(SNR) in satellite communication, this paper proposes a Red and Blue Frequency Shift Discriminator(RBFSD) based on the pseudo-noise(PN) sequence.The paper derives that the cross-correlation function on the Doppler domain exhibits the characteristic of a Sinc function. Therefore, it applies modulation onto the Delay-Doppler domain using PN sequence and adjusts Doppler frequency estimation by red-shifting or blue-shifting. Simulation results show that the performance of Doppler frequency estimation is close to the Cramér-Rao Lower Bound when the SNR is greater than -15dB. The proposed algorithm is about 1/D times less complex than the existing PN pilot sequence algorithm, where D is the resolution of the fractional Doppler.

关键词： channel estimation communication and navigation integration Orthogonal Time Frequency and Space pseudo-noise sequence red-blue frequency shift discriminator

The Integration Strategy of Class Teacher Management and Mathematics Teaching

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Journal of Contemporary Educational Research 2024年第6期8卷 142-147页

作者： chao wen Chongqing Nankai(Rongqiao)Secondary School Chongqing 400069China

The professional and moral education of high school mathematics teachers will make classroom management work better,but their work pressure will also lead to classroom management problems.To do a good job in high school class teacher management and organically integrate it with mathematics teaching,we need to start from two aspects:mathematics teaching class teachers and class teacher work teaching,and penetrate mathematical thinking into daily classroom management,moral education,and classroom culture construction.Based on the attributes of the subject,we guide high school students to reflect after class to stimulate their self-management initiative through the cultivation of qualified class representatives.In addition,it is necessary to skillfully resolve classroom generative problems,change the roles of teachers and students,and integrate classroom management with mathematics teaching.

关键词： High school class teacher Class teacher management Mathematics teaching Integration strategies

Diagnostic value associated with the combination of saliva pepsin and microorganisms in functional heartburn and gastroesophageal reflux disease

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World Journal of Gastroenterology 2024年第19期30卷 2612-2614页

作者： Yu-Qi Huang chao Yang wen Luo Department of Stomatology The First Affiliated Hospital of Hainan Medical UniversityHaikou 570102Hainan ProvinceChina School of Stomatology Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Research and Development Department Shenzhen Uni-medica Technology Co.LtdShenzhen 518051Guangdong ProvinceChina Department of Stomatology The People’s Hospital of LonghuaShenzhen 518109Guangdong ProvinceChina

Heartburn is a common symptom shared by both gastroesophageal reflux disease(GERD)and functional heartburn(FHB),which can make it challenging to differentiate between the two conditions.However,examining oral manifestations of GERD can be a cost-effective and readily available method to aid in this differentiation process.It may serve as a valuable tool in distinguishing GERD from FHB.

关键词： Gastroesophageal reflux disease Gastric acid Heartburn Differential diagnosis Epidemiology Oral manifestations Prevalence Risk factors Dental erosion Periodontal diseases

Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： chao-Yue Sun wen Li Hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2)) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

A Review on Engineering Design for Enhancing Interfacial Contact in Solid-State Lithium–Sulfur Batteries

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Nano-Micro Letters 2024年第4期16卷 219-252页

作者： Bingxin Qi Xinyue Hong Ying Jiang Jing Shi Mingrui Zhang wen Yan chao Lai School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116JiangsuPeople’s Republic of China

The utilization of solid-state electrolytes(SSEs)presents a promising solution to the issues of safety concern and shuttle effect in Li–S batteries,which has garnered significant interest recently.However,the high interfacial impedances existing between the SSEs and the electrodes(both lithium anodes and sulfur cathodes)hinder the charge transfer and intensify the uneven deposition of lithium,which ultimately result in insufficient capacity utilization and poor cycling stability.Hence,the reduction of interfacial resistance between SSEs and electrodes is of paramount importance in the pursuit of efficacious solid-state batteries.In this review,we focus on the experimental strategies employed to enhance the interfacial contact between SSEs and electrodes,and summarize recent progresses of their applications in solidstate Li–S batteries.Moreover,the challenges and perspectives of rational interfacial design in practical solid-state Li–S batteries are outlined as well.We expect that this review will provide new insights into the further technique development and practical applications of solid-state lithium batteries.

关键词： Solid-state lithium–sulfur batteries Solid-state electrolytes Electrode/electrolyte interface Interfacial engineering Enhancing interfacial contact

26-electrons redox-active polyoxovanadate clusters for aqueous zincion batteries

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Nano Research 2024年第5期17卷 4047-4054页

作者： Yimin Xing wen Yan Haiyang Wu Peng Huang chao Wang chao Lai School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116China

Aqueous zinc-ion batteries(ZIBs)are attaining increasing attention for their high safety and low cost.Despite significant progresses in realizing high-performance cathode material for ZIBs,simultaneously endowing them with high capacity and fast-charging capability,the long-term cycling stability remains a major unsolved challenge.In this work,a polyoxovanadate cluster of(NH_(4))_(8)[V_(19)O_(41)(OH)_(9)]·11H_(2)O(NOV)is defined as a cathode material for ZIBs that contains mixed-valence vanadium sites(V^(4+)and V^(5+)).A maximum of 26 electrons can be accommodated in one[V_(19)O_(41)(OH)_(9)]^(8-){V_(19)O_(50)}cluster,contributing to the high theoretical specific capacity of 328 mA·h·g^(-1).The Ti_(3)C_(2)T_(x) MXene nanosheets are incorporated into NOV with the help of ionic liquid(IL)linkers to restrain the dissolution of vanadium species and facilitate electron transport across the electrode.The interfacial bonding,anion exchange,and electrostatic interactions among NOV and MXene are provided by IL liquid.The nanohybrid of NOV-IL-MXene endows excellent contact between MXene and NOV,thereby enhanced charge transfer is observed at interface.Subsequently,the as-synthesized NOV-IL-MXene cathodes exhibit high discharge capacity of 413 mA·h·g^(-1) at 0.2 A·g^(-1) even at high mass loading of 5.2 mg·cm^(-2),remarkable rate performance of 182 mA·h·g^(-1) at 10 A·g^(-1),and impressive cycling stability of 94%capacity retention after 2000 cycles.This work opens up new opportunities to develop advanced polyoxovanadate hybrid cathodes for low-cost and high-performance aqueous ZIBs.

关键词： polyoxovanadate MXene composite materials cathodes zinc-ion batteries

Thermodynamic geometry of the RN-Ad S black hole and non-local observables

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Communications in Theoretical Physics 2024年第2期76卷 137-144页

作者： chao Wang Bin Wu Zhen-Ming Xu wen-Li Yang Institute of Physics Shaanxi University of TechnologyHanzhong 723000China School of Physics Northwest UniversityXi'an 710127China Institute of Modern Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

This paper studies the thermodynamic geometry of the Reissner–Nordstr?m-anti-de Sitter(RN-AdS)black hole via detection of the non-local observables in the dual field theory,including the entanglement entropy and equal-time two-point correlation function.With the dimensional analysis,we construct the principle of corresponding states of black hole thermodynamics.As a result,our findings can be applied to black holes with different Ad S backgrounds.In this sense,the probe of the thermodynamic geometry of the RN-Ad S black hole though the non-local observables in dual field theory has been confirmed numerically.

关键词： black hole thermodynamic thermodynamic geometry phase transition non-local observables

Reactive oxygen species:Multidimensional regulators of plant adaptation to abiotic stress and development

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Journal of Integrative Plant Biology 2024年第3期66卷 330-367页

作者： Pengtao Wang wen-Cheng Liu chao Han Situ Wang Ming-Yi Bai Chun-Peng Song State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 475004China The Key Laboratory of Plant Development and Environmental Adaptation Biology Ministry of EducationSchool of Life SciencesShandong UniversityQingdao 266237China Faculty of Science McGill UniversityMontreal H3B1X8Canada

Reactive oxygen species(ROS)are produced as undesirable by-products of metabolism in various cellular compartments,especially in response to unfavorable environmental conditions,throughout the life cycle of plants.Stressinduced ROS production disrupts normal cellular function and leads to oxidative damage.To cope with excessive ROS,plants are equipped with a sophisticated antioxidative defense system consisting of enzymatic and non-enzymatic components that scavenge ROS or inhibit their harmful effects on biomolecules.Nonetheless,when maintained at relatively low levels,ROS act as signaling molecules that regulate plant growth,development,and adaptation to adverse conditions.Here,we provide an overview of current approaches for detecting ROS.We also discuss recent advances in understanding ROS signaling,ROS metabolism,and the roles of ROS in plant growth and responses to various abiotic stresses.

关键词： abiotic stress growth and development plant reactive oxygen species

Molecular recognition of cyclophanes in water

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Chinese Chemical Letters 2024年第5期35卷 32-44页

作者： Fang-Yuan Chen wen-chao Geng Kang Cai Dong-Sheng Guo College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China College of Chemistry Nankai UniversityTianjin 300071China

Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular chemistry.The mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular level.Over the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition properties.Among them,cyclophanes represent an important family of macrocyclic receptors that have been extensively explored.The aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous environments.Pioneered by Koga et al.,who reported the first inclusion complex of cyclophanes in water and solid state,numerous water-soluble cyclophanes,including derivatives of blue box,calixarenes,resorcinarenes,pillararenes,octopusarenes,biphenarenes,coronarenes,and naphthotubes,etc.,have been synthesized and subjected to investigation of the recognition capabilities in aqueous solutions.This review provides an overview of cyclophane receptors designed to bind organic guests in water.We categorize them into two classes based on the modifications made to their hydrophobic cavities:those with“exo-functionalized hydrophobic cavities”and those with“endo-functionalized hydrophobic cavities”.We introduce their distinctive features and discuss strategies to enhance recognition affinity and selectivity.This review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.

关键词： Biomimetic receptor Cyclophane Molecular recognition Hydrophobic effect High-affinity Macrocycles