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Control Theory and Technology 2024年第3期22卷 455-467页

作者： R.h.harsha Nawarathna Yuandan Lin Yuan Wang Department of Mathematical Sciences Florida Atlantic UniversityBoca RatonFL 33431USA

We consider how small delays affect the integral-input-to-state stability(iss)property for a *** result is similar to the input-to-state stability(Iss)result obtained in[1]:the iss property will be preserved in a practical and semi-global manner if the delay interval is small ***,since the iss quantifies the robust stability in terms of a generalized Li norm of the inputs instead of a generalized Loo norm of the inputs for the Iss case,the techniques and proofs for the Iss case do not apply to the iss case *** the proofs in[1]are based on the Lyapunov-Razumikhin approach,our proofs are based on the iss-Lyapunov functions for the zero-delay *** addition to the interest by its own in showing how the iss property is affected by small delays,the result also serves to the study of the iss property for singularly perturbed systems.

关键词： Integral-input-to-state stability Nonlinear systems Small delays Lyapunov method

Role of marine natural products in the development of antiviral agents against SARS‑CoV‑2:potential and prospects

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Marine Life Science & Technology 2024年第2期6卷 280-297页

作者： D.P.Nagahawatta N.M.Liyanage Thilina U.Jayawardena h.h.A.C.K.Jayawardhana Seong‑hun Jeong hyung‑Jun Kwon You‑Jin Jeon Department of Marine Life Sciences Jeju National UniversityJeju 690-756Republic of Korea Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresTrois-RivièresQC G8Z 4M3Canada Marine Science Institute Jeju National UniversityJeju 63333Republic of Korea Functional Biomaterial Research Center Korea Research Institute of Bioscience and BiotechnologyJeongeup-siRepublic of Korea

A novel coronavirus,known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has surfaced and caused global concern owing to its ***-CoV-2 is the causative agent of coronavirus disease 2019;however,it was only discovered at the end of the year and was considered a pandemic by the World health ***,the develop-ment of novel potent inhibitors against SARS-CoV-2 and future outbreaks is urgently *** naturally occurring bioactive substances have been studied in the clinical setting for diverse *** intricate infection and replication mechanism of SARS-CoV-2 offers diverse therapeutic drug targets for developing antiviral medicines by employing natural products that are safer than synthetic *** natural products(MNPs)have received increased attention in the development of novel drugs owing to their high diversity and ***,this review article investigates the infection and replication mechanisms,including the function of the SARS-CoV-2 genome and ***,we highlighted anti-SARS-CoV-2 therapeutic intervention efforts utilizing MNPs and predicted SARS-CoV-2 inhibitor design.

关键词： SARS-CoV-2 Marine natural products Drug targets Inhibitors

A vectorial model for the nonlinear gradient force exerted on metallic Rayleigh nanoparticles

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Chinese Optics Letters 2024年第2期22卷 207-213页

作者：朱政张聿全闵长俊 Aurèle J.LAdam h.Paul Urbach 袁小聪 Research Center for humanoid Sensing Research Institute of Intelligent SensingZhejiang LabHangzhou 311100China Nanophotonics Research Center Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands

Optical tweezers have proved to be a powerful tool with a wide range of *** gradient force plays a vital role in the stable optical trapping of *** scalar method is convenient and effective for analyzing the gradient force in traditional optical ***,when the third-order nonlinear effect of the nano-object is stimulated,the scalar method cannot adequately present the optical response of the metal nanoparticle to the external optical ***,we propose a theoretical model to interpret the nonlinear gradient force using the vector *** combining the optical Kerr effect,the polarizability vector of the metallic nanoparticle is derived.A quantitative analysis is obtained for the gradient force as well as for the optical potential *** vector method yields better agreement with reported experimental *** suggest that this method could lead to a deeper understanding of the physics relevant to nonlinear optical trapping and binding phenomena.

关键词： gradient forces nonlinear effect metallic nanoparticles

不同结构AlGaN基深紫外发光二极管性能研究

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不同结构AlGaN基深紫外发光二极管性能研究

作者： ALMAZROI SALWA SAAD h 北京化工大学

学位级别：硕士

基于AlGaN材料的深紫外发光二极管(DUV LED)具有体积小、能耗低、工作电流小、亮度高和发光响应速度快等优点,发光具有很强的杀菌效果,是汞灯的理想替代品,广泛地用于生物研究和污水处理领域。同时也可以为生物实验室、实验用器具及医... 详细信息

基于AlGaN材料的深紫外发光二极管(DUV LED)具有体积小、能耗低、工作电流小、亮度高和发光响应速度快等优点,发光具有很强的杀菌效果,是汞灯的理想替代品,广泛地用于生物研究和污水处理领域。同时也可以为生物实验室、实验用器具及医院手术室、医疗器具等消毒,在微制造技术和环境科学领域也大有可为,而且还可以用于制造侦测有毒粒子的传感器。由于其很容易与晶体管和集成电路配套使用,是近几年来迅速崛起的半导体光电器件。然而由于材料极化特性、器件结构等一系列因素,导致器件的性能难以与同族材料制备的可见光LED比拟,严重阻碍了其产业化进程。针对上述难题,本论文设计构建了系列DUV LED器件结构,并采用APSYS软件,研究了有源区结构、电子阻挡层结构及p型区结构对器件性能的影响机理,并对器件结构进行了优化设计,获得了以下研究成果。(1)深入研究了有源区结构对器件性能的影响,研究发现在一定范围内增加量子阱(QW)和量子阱势垒(QB)层厚度可以提高载流子注入效率和辐射复合效率,提升内部量子效率(IQE)和总功率。然而,超过一定阈值后,由于量子限制stark效应,导致IQE下降。在本工作中,当QW和QB的厚度分别为3.50、10.00 nm时,器件性能最佳。I-V曲线显示,QW和QB厚度的增加,对器件开启电压几乎没有影响。该研究强调了材料组成、能带对齐和厚度在器件性能优化方面的重要性。优化QW和QB层的厚度可以极大地提高内部量子效率(IQE)和LED总功率。(2)探讨了超晶格电子阻挡层(SL-EBL)对AlGaN DUV LED性能的影响。深入研究了SL-EBL厚度对器件功能的影响,揭示了结构参数和LED性能之间微妙的关系。研究表明,SL-EBL厚度的变化对AlGaN DUV LED的效率有重大影响,随着SL-EBL厚度的增加,IQE和总LED功率均呈现出一致的降低。在所有结构中,较薄的SL-EBL厚度为1.00 nm时可实现最佳性能。此外,分析还探讨了SL-EBL结构和不同铝(Al)组分对SL-EBL性能的影响。对带隙能量的检查显示,较大的SL-EBL层导致导带和价带边缘发生显著变化,表明载流子限制增强,载流子迁移性降低。通过优化SL-EBL结构,可以达到更高的IQE,达到68.37%,强调了精心设计和组成在提高LED性能中的重要性。(3)研究探讨了p型层内Al化合物浓度的变化对器件特性的影响。审查了AlGaN DUV LED的Al比例与效率之间的相关性,以及它们各自的厚度。在优化Al浓度之后,确定了7).(6./7).(6.的配置,第一层厚度为10 nm,第二层厚度为10 nm,可以实现72.12%的内部量子效率(IQE)。该配置在注入电流为500 A/m时,还可实现144.24 W/m的输出功率。

关键词： AlGaN 发光二极管有源区 EBL AlGaN器件结

Ballistic design and testing of a composite armour reinforced by CNTs suitable for armoured vehicles

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Defence Technology（防务技术） 2024年第2期32卷 173-195页

作者： Evangelos Ch.Tsirogiannis Evangelos Daskalakis Mohamed h.hassan Abdalla M.Omar Paulo Bartolo EODh SA Research and Development DepartmentLakkoma Chalkidikis63080Greece School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK Singapore Centre for 3D Printing School of Mechanical and Aerospace EngineeringNanyang Technological University639798Singapore

This paper is investigating the use of composite armour reinforced by nanomaterials, for the protection of light armoured(LAV) and medium armoured military vehicles(MAV), and the interaction between the composite materials and high-performance ballistic projectiles. Four armour materials, consisted of front hybrid fibre reinforced polymer cover layer, ceramic strike-face, fibre reinforced polymer intermediate layer and the metal matrix composite reinforced backplate, were manufactured and assembled by adhesive technology. The proposed laminated protection system is suitable for armoured ground vehicles;however, it could be used as armour on ground, air and naval platforms. The design of the protection system, including material selection and thickness, was elaborated depending on the performance requirements of Level 4 + STANAG 4569 military standard(projectile 14.5 mm × 114 mm API B32) and especially on a design philosophy which is analysed with the specifications. The backplate of this new composite is a hybrid material of Metal Matrix Composite(MMC) reinforced with carbon nanotubes(CNTs), manufactured with the use of powder metallurgy technique. The composite backplate material was morphologically, mechanically and chemically analysed. Results show that all plates are presenting high mechanical properties and ballistic characteristics, compared to commonly used armour plates. Real military ballistic tests according to AEP-STANAG 4569 were carried out for the total composite armour systems. After the ballistic tests, AA2024-CNT3 showed the best protection results, compared with the other plates(AA2024-CNT1 and AA2024-CNT2), with the projectile being unable to fully penetrate the composite plate.

关键词： Passive armour protection Protective armour Ballistic performance hybrid composites Vehicle protection

Crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria M.Manhas A.K.Bedyal Ankush Vij h.C.Swart Vinay Kumar Department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StatePO.Box 339BloemfonteinZA 9300South Africa

highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,Ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

Trehalose:A sugar molecule involved in temperature stress management in plants

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The Crop Journal 2024年第1期12卷 1-16页

作者： Ali Raza Savita Bhardwaj Md Atikur Rahman Pedro García-Caparrós Madiha habib Faisal Saeed Sidra Charagh Christine h.Foyer Kadambot h.M.Siddique Rajeev K.Varshney College of Agriculture Fujian Agriculture and Forestry University(FAFU)Fuzhou 350002FujianChina Department of Botany School of Bioengineering and BiosciencesLovely Professional UniversityPhagwara 144411India Department of Botany MCM DAV CollegeKangraHimachal Pradesh 176001India Grassland and Forage Division National Institute of Animal ScienceRural Development AdministrationCheonan 31000Republic of Korea Agronomy Department of Superior School Engineering University of AlmeríaAlmeríaSpain National Institute for Genomics and Advanced Biotechnology National Agricultural Research CentrePark Rd.Islamabad 45500Pakistan Agriculture Health and Environment DepartmentNatural Resources InstituteFaculty of Engineering&ScienceUniversity of GreenwichKent ME44TBUK State Key Laboratory of Rice Biology China National Rice Research InstituteChinese Academy of Agricultural SciencesHangzhouZhejiangChina School of Biosciences College of Life and Environmental SciencesUniversity of BirminghamEdgbaston B152TTUK The UWA Institute of Agriculture The University of Western AustraliaCrawleyPerth 6009Australia WA State Agricultural Biotechnology Centre Centre for Crop and Food InnovationFood Futures InstituteMurdoch UniversityMurdochWA 6150Australia

Trehalose(Tre)is a non-reducing disaccharide found in many species,including bacteria,fungi,invertebrates,yeast,and even plants,where it acts as an osmoprotectant,energy source,or protein/membrane *** relatively small amounts in plants,Tre concentrations increase following exposure to abiotic ***-6-phosphate,a precursor of Tre,has regulatory functions in sugar metabolism,crop production,and stress *** the various abiotic stresses,temperature extremes(heat or cold stress)are anticipated to impact crop production worldwide due to ongoing climate *** small amounts of Tre can mitigate negative physiological,metabolic,and molecular responses triggered by temperature *** also interacts with other sugars,osmoprotectants,amino acids,and phytohormones to regulate metabolic reprogramming that underpins temperature stress *** plants expressing Tre-synthesis genes accumulate Tre and show improved stress ***-wide studies of Tre-encoding genes suggest roles in plant growth,development,and stress *** review discusses the functions of Tre in mitigating temperature stress—highlighting genetic engineering approaches to modify Tre metabolism,crosstalk,and interactions with other molecules—and in-silico approaches for identifying novel Tre-encoding genes in diverse plant *** consider how this knowledge can be used to develop temperature-resilient crops essential for sustainable agriculture.

关键词： Abiotic stress Gene expression Genetic engineering Osmolyte Trehalose-6-phosphate

PdPtCuNiP高熵非晶合金蠕变机理研究

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力学学报 2024年

作者：段亚娟徐宗睿郝奇 h.Kato 乔吉超西北工业大学力学与土木建筑学院加泰罗尼亚理工大学能源技术研究所物理系日本东北大学材料研究所

本研究以Pd20Pt20Cu20Ni20P20高熵非晶合金作为研究载体,通过蠕变循环加载及循环加载-回复实验,着重考察了蠕变变形、准稳态蠕变速率、蠕变应力指数和弛豫时间分布谱演变规律,系统探索了温度、循环加载及回复时间对其蠕变行为的影响.研... 详细信息

本研究以Pd20Pt20Cu20Ni20P20高熵非晶合金作为研究载体,通过蠕变循环加载及循环加载-回复实验,着重考察了蠕变变形、准稳态蠕变速率、蠕变应力指数和弛豫时间分布谱演变规律,系统探索了温度、循环加载及回复时间对其蠕变行为的影响.研究结果表明，该合金的蠕变行为明显依赖于温度和应力，低温及低应力环境下合金表现出较好的抗蠕变性能，主要以弹性变形为主.随着温度增加，合金抗蠕变能力减弱，粘弹性（粘塑性）变形成为主导.循环应力在低温下对蠕变变形影响较小，而在高温下其影响显著，表明循环载荷能加剧蠕变行为，导致准稳态蠕变速率上升.回复时间对合金的瞬时弹性变形和滞弹性变形有显著影响，但对粘塑性变形的调节作用有限.卸载后合金变形能力逐渐增强，蠕变抑制得到缓解.此外，变形单元弛豫时间的广泛分布和对循环应力的敏感反应，揭示了蠕变机制的复杂性和多时间尺度的结构演化.本研究通过系统的实验和分析，深化了对高熵非晶合金蠕变行为及其调控机制的理解.为高性能高熵非晶合金的设计和应用提供了重要的理论依据和实践指导，对未来开发更具抗蠕变能力的先进材料具有一定意义.

关键词：高熵非晶合金蠕变滞弹性变形动力学微观结构非均匀性

An introductory review of swarm technology for spacecraft on-orbit servicing

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International Journal of Mechanical System Dynamics 2024年第1期4卷 3-21页

作者： El Ghali Asri Zheng h.Zhu Department of Mechanical Engineering York UniversityTorontoOntarioCanada

This review paper presents a comprehensive evaluation and forward-looking perspective on the underexplored topic of servicing target objects using spacecraft *** targets can be known or unknown,cooperative or uncooperative,and pose significant challenges in modern space operations due to their inherent complexity and *** servicing space objects is vital for active debris removal and broader on-orbit servicing tasks such as satellite maintenance,repair,refueling,orbital assembly,and *** effort has been invested in the literature to explore the servicing of targets using a single *** its advantages and benefits,this paper expands the discussion to encompass a swarm approach to the *** review covers various single-spacecraft approaches and presents a critical examination of the existing,although limited,body of work dedicated to servicing orbital objects using multiple *** focus is also broadened to include some influential studies concerning the characterization,capture,and manipulation of physical objects by general multiagent systems,a subject with significant parallels to the core interest of this ***,this article also delves into the realm of simultaneous localization and mapping,highlighting its application within close-proximity operations in space,especially when dealing with unknown uncooperative *** attention is paid to the benefits that this field can receive from distributed multiagent ***,an exploration of the promising field of swarm robotics is presented,with an emphasis on its potential to revolutionize the servicing of orbital target ***,a survey of general research directly engaging swarms in the orbital context is *** review aims to bridge the knowledge gap and stimulate further research in the underexplored domain of servicing space targets with spacecraft swarms.

关键词： space robotics on-orbit servicing close-proximity operations guidance and navigation swarm robotics multiagent systems object capture and manipulation simultaneous localization and mapping

A case of post traumatic mitral chordae rupture mimicking acute respiratory distress syndrome

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World Journal of Emergency Medicine 2024年第4期15卷 322-324页

作者： hülya Deniz Misir Nalan Demir Ferit Kasimzade Cansu Yahşi Intensive Care Department Ankara Bilkent City HospitalAnkara 06800Turkiye Intensive Care Department University of Health Sciences Ankara Bilkent City HospitalAnkara 06800Turkiye Cardiovascular Surgery Department Ankara Bilkent City HospitalAnkara 06800Turkiye Pulmonary Medicine Department University of Health Sciences Ankara Bilkent City HospitalAnkara 06800Turkiye

Traumatic mitral chordae rupture is a rare and known cause of acute mitral valve regurgitation and de novo heart *** pathologies in a trauma patient may mask the findings of de novo heart failure due to mitral chordae *** patients may also have other potential pre-diagnoses that could explain symptoms related to heart failure,such as tachycardia,circulatory shock,and acute *** possibility of traumatic chordae tendinea rupture being a preventable cause of mortality should be carefully evaluated.

关键词： rupture mitral acute