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Interface Engineering of Titanium Nitride Nanotube Composites for Excellent Microwave Absorption at Elevated Temperature

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Nano-Micro Letters 2024年第9期16卷 147-160页

作者： Cuiping Li Dan Li Shuai zhang Long Ma lei zhang* Jingwei zhang Chunhong Gong College of Chemistry and Molecular Sciences Henan UniversityKaifeng 475004People’s Republic of China National and Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004People’s Republic of China

Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently,the development of high-performance EMWA materials with good impedance matching and strong loss ability in wide temperature spectrum has emerged as a top priority.Herein,due to the high melting point,good electrical conductivity,excellent environmental stability,EM coupling effect,and abundant interfaces of titanium nitride(TiN)nanotubes,they were designed based on the controlling kinetic diffusion procedure and Ostwald ripening process.Benefiting from boosted heterogeneous interfaces between TiN nanotubes and polydimethylsiloxane(PDMS),enhanced polarization loss relaxations were created,which could not only improve the depletion efficiency of EMWA,but also contribute to the optimized impedance matching at elevated temperature.Therefore,the TiN nanotubes/PDMS composite showed excellent EMWA performances at varied temperature(298-573 K),while achieved an effective absorption bandwidth(EAB)value of 3.23 GHz and a minimum reflection loss(RLmin)value of−44.15 dB at 423 K.This study not only clarifies the relationship between dielectric loss capacity(conduction loss and polarization loss)and temperature,but also breaks new ground for EM absorbers in wide temperature spectrum based on interface engineering.

关键词： TiN nanotubes Interface engineering Polarization loss Impedance matching Electromagnetic wave absorption performance

Mutual aid instead of mutual restraint:interactive probing for topological charge and phase of a vortex beam of large aberrations

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Photonics Research 2024年第1期12卷 172-182页

作者： SHENGYANG WU BENLI YU lei zhang Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of EducationAnhui UniversityHefei 230601China Information Materials and Intelligent Sensing Laboratory of Anhui Province Anhui UniversityHefei 230601China

An imperfect propagation environment or optical system would introduce wavefront aberrations to vortex beams.The phase aberrations and orbital angular momentum in a vortex beam are proved to be mutually restrictive in parameter measurement.Aberrations make traditional topological charge(TC)probing methods ineffective while the phase singularity makes phase retrieval difficult due to the aliasing between the wrapped phase jump and the vortex phase jump.An interactive probing method is proposed to make measurements of the aberrated phase and orbital angular momentum in a vortex beam assist rather than hinder each other.The phase unwrapping is liberated from the phase singularity by an annular shearing interference technique while the TC value is determined by a Moirétechnique immune to aberrations.Simulation and experimental results proving the method effective are presented.It is of great significance to judge the characteristics of vortex beams passing through nonideal environments and optical systems.

关键词： vortex topological beam

Digital Twin Modeling Enabled Machine Tool Intelligence:A Review

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 29-54页

作者： lei zhang Jianhua Liu Cunbo Zhuang School of Mechanical Engineering Tianjin University of CommerceTianjin 300134China Laboratory of Digital Manufacturing School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 10081China

Machine tools,often referred to as the“mother machines”of the manufacturing industry,are crucial in developing smart manufacturing and are increasingly becoming more intelligent.Digital twin technology can promote machine tool intelligence and has attracted considerable research interest.However,there is a lack of clear and systematic analyses on how the digital twin technology enables machine tool intelligence.Herein,digital twin modeling was identified as an enabling technology for machine tool intelligence based on a comparative study of the characteristics of machine tool intelligence and digital twin.The review then delves into state-of-the-art digital twin modelingenabled machine tool intelligence,examining it from the aspects of data-based modeling and mechanism-data dual-driven modeling.Additionally,it highlights three bottleneck issues facing the field.Considering these problems,the architecture of a digital twin machine tool(DTMT)is proposed,and three key technologies are expounded in detail:Data perception and fusion technology,mechanism-data-knowledge hybrid-driven digital twin modeling and virtual-real synchronization technology,and dynamic optimization and collaborative control technology for multilevel parameters.Finally,future research directions for the DTMT are discussed.This work can provide a foundation basis for the research and implementation of digital-twin modeling-enabled machine tool intelligence,making it significant for developing intelligent machine tools.

关键词： Machine tool Digital twin Smart manufacturing Synchronization

Molecular regulation of the key specialized metabolism pathways in medicinal plants

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Journal of Integrative Plant Biology 2024年第3期66卷 510-531页

作者： Min Shi Siwei zhang Zizhen Zheng Itay Maoz lei zhang Guoyin Kai Zhejiang Provincial International S&T Cooperation Base for Active Ingredients of Medicinal and Edible Plants and Health Zhejiang Provincial Key TCM Laboratory for Chinese Resource Innovation and TransformationSchool of Pharmaceutical SciencesJinhua AcademyZhejiang Chinese Medical UniversityHangzhou 310053China Department of Postharvest Science Agricultural Research OrganizationVolcani CenterRishonLeZion 7505101Israel Department of Pharmaceutical Botany School of PharmacyNaval Medical UniversityShanghai 200433China

The basis of modern pharmacology is the human ability to exploit the production of specialized metabolites from medical plants,for example,terpenoids,alkaloids,and phenolic acids.However,in most cases,the availability of these valuable compounds is limited by cellular or organelle barriers or spatio-temporal accumulation patterns within different plant tissues.Transcription factors(TFs)regulate biosynthesis of these specialized metabolites by tightly controlling the expression of biosynthetic genes.Cutting-edge technologies and/or combining multiple strategies and approaches have been applied to elucidate the role of TFs.In this review,we focus on recent progress in the transcription regulation mechanism of representative high-value products and describe the transcriptional regulatory network,and future perspectives are discussed,which will help develop high-yield plant resources.

关键词： biosynthesis medicinal plants omics secondary metabolism transcription factors

Efficacy of physiological seawater nasal irrigation for the treatment of children with SARS-CoV-2 Omicron BA.2 variant infection:a randomized controlled trial

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World Journal of Pediatrics 2024年第5期20卷 461-469页

作者： Ji-lei Lin Fen zhang Yan-Bo Li Shu-Hua Yuan Jin-Hong Wu Jing zhang lei zhang Yi He Jie Chen Yong Yin Department of Respiratory Medicine Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina University of British Columbia VancouverCanada Information Technology Department Shanghai Children’s Medical Center National Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina Department of Otorhinolaryngology Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina Department of Respiratory Medicine Sanya Women and Children’s Hospital Affiliated to Hainan Medical CollegeHainan Branch of Shanghai Children’s Medical CenterSanyaChina Department of Respiratory Medicine Linyi Maternal and Child Healthcare HospitalLinyiChina Shanghai Children’s Medical Center Pediatric Medical Complex(Pudong) ShanghaiChina Pediatric AI Clinical Application and Research Center Shanghai Children’s Medical CenterShanghaiChina

Background Saline nasal irrigation is an effective therapy for relieving common cold symptoms.This study aimed to investigate and explore the efficacy of physiological seawater nasal irrigation(PSNI)on children with mild and asymptomatic infection with Omicron.Methods This randomized controlled trial was conducted in Shanghai,China,and 403 children with mild and asymptomatic infection with Omicron were included.These children were allocated into the PSNI group and the control group.The primary outcome was the duration of viral shedding(DVS),and the secondary outcome was the change in clinical symptoms.Results The median age of all participants was 5.59(6.26)years old.The DVS was significantly shorter in the PSNI group[2.40(1.13)]than in the control group[3.09(2.14)](P=0.014).The multivariable Cox regression model also showed that patients in the PSNI group had an increased probability of shorter DVS compared with patients in the control group[hazard ratio(HR),1.27;95%confidence interval(CI),1.04–1.55;P=0.017].Subgroup analysis suggested that the DVS of patients without full vaccination was significantly reduced in the PSNI group.The proportions of runny nose and stuffy nose were apparently reduced in the first three days in the PSNI group or the control group,but there was no evidence showing that PSNI contributes to the benefit compared with the control group.Conclusion PSNI can reduce the DVS of patients with mild and asymptomatic infection with SARS-CoV-2 Omicron BA.2 variant.

关键词： Children Duration of viral shedding Omicron Physiological seawater nasal irrigation

Polarization-driven multifunctional organohydrogels with strain sensitivity toward electromagnetic wave absorption

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Nano Research 2024年第6期17卷 5688-5697页

作者： Yunfei zhang lei zhang Bingqian Zhou Yishan Gao Baoliang zhang School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072China Shaanxi Engineering and Research Center for Functional Polymers on Adsorption and Separation Sunresins New Materials Co.Ltd.Xi’an 710072China

Rapid advancements in flexible electronics and military applications necessitate high-performance electromagnetic wave(EMW)absorbers.While huge breakthroughs in achieving high-attenuation microwave absorption,conventional EMW absorbing materials have single function and ambiguous absorption mechanisms.Herein,numerous gel-type absorbers are fabricated by introducing“regulators”into poly(acrylamide-co-acrylic acid)(P(AM-co-AA))networks through radical polymerization in a glycerol-water mixed solvent.The dielectric constant and EMW absorption performance of the gels are precisely predicted by adjusting monomer concentration,the ratio of glycerol/water,and the content of the regulators.Notably,A_(6)G_(20)T_(20)-2 exhibits promising absorption performance with a minimum reflection loss(RL_(min))of-33.8 dB at 12.4 GHz.The effective absorption bandwidth(EAB)covers the entire X-band(8.2-12.4 GHz)at a thickness of 2.7 mm.A_(6)G_(20)T_(20)-2 also has sensitive deformation responses and excellent tensile strength,adhesiveness,self-healing and anti-freezing properties.Overall,this work not only provides insight into the polarization loss mechanism of the gels as the result of high correlation between EMW absorbing properties and molecular polarization,but also offers an important reference for developing functional protective materials because of the rich functionalities and efficient protective capabilities of the gels.

关键词： organohydrogels molecular polarization microwave absorption strain sensor

Integrated Active Suspension and Anti-Lock Braking Control for Four-Wheel-Independent-Drive Electric Vehicles

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 87-98页

作者： Ze Zhao lei zhang Xiaoling Ding Zhiqiang zhang Shaohua Li Liang Gu National Engineering Research Center for Electric Vehicles Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

This paper presents an integrated control scheme for enhancing the ride comfort and handling performance of a four-wheel-independent-drive electric vehicle through the coordination of active suspension system(ASS)and anti-lock braking system(ABS).First,a longitudinal-vertical coupled vehicle dynamics model is established by integrating a road input model.Then the coupling mechanisms between longitudinal and vertical vehicle dynamics are analyzed.An ASS-ABS integrated control system is proposed,utilizing an H∞controller for ASS to optimize load transfer effect and a neural network sliding mode control for ABS implementation.Finally,the effectiveness of the proposed control scheme is evaluated through comprehensive tests conducted on a hardware-in-loop(HIL)test platform.The HIL test results demonstrate that the proposed control scheme can significantly improve the braking performance and ride comfort compared to conventional ABS control methods.

关键词： Four-wheel-independent-drive electric vehicles Active suspension system(ASS) Anti-lock braking system(ABS) Vertical-longitudinal vehicle dynamics

Revealing excited states of rotational Bose-Einstein condensates

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The Innovation 2024年第1期5卷 41-48页

作者： Jianyuan Yin Zhen Huang Yongyong Cai Qiang Du lei zhang School of Mathematical Sciences Laboratory of Mathematics and Applied MathematicsPeking UniversityBeijing 100871China Department of Mathematics National University of SingaporeSingapore 119076Singapore Department of Mathematics University of CaliforniaBerkeleyBerkeleyCA 94720USA School of Mathematical Sciences Beijing Normal UniversityBeijing 100875China Department of Applied Physics and Applied Mathematics and Data Science Institute Columbia UniversityNew YorkNY 10027USA Beijing International Center for Mathematical Research Center for Quantitative BiologyCenter for Machine Learning ResearchPeking UniversityBeijing 100871China

Rotational Bose-Einstein condensates can exhibit quantized vortices as topological excitations.In this study,the ground and excited states of the rotational Bose-Einstein condensates are systematically studied by calculating the stationary points of the Gross-Pitaevskii energy functional.Various excited states and their connections at different rotational frequencies are revealed in solution landscapes constructed with the constrained high-index saddle dynamics method.Four excitation mechanisms are identified:vortex addition,rearrangement,merging,and splitting.We demonstrate changes in the ground state with increasing rotational frequencies and decipher the evolution of the stability of ground states.

关键词： method rotational excited

HIV Infection and Associated Factors Among Out-of-School MSM Aged 16–24 Years—6 Cities and Tianjin Municipality,China,2022–2023

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China CDC weekly 2024年第3期6卷 45-50页

作者： Hui Liu Qiyu Zhu lei zhang Yujing Liu Peng Xu Mengjie Han National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Chinese Association of STD and AIDS Prevention and Control BeijingChina Beijing Chaoyang Kangzhong Health and Education Center BeijingChina

What is already known about this topic?Approximately 80%of newly diagnosed human immunodeficiency virus(HIV)cases among individuals aged 15–24 years in China are attributed to out-ofschool youth.What is added by this report?This study presents findings on HIV prevalence and comprehensive insights into HIV service utilization,risky behaviors,and prevention knowledge among young out-of-school men who have sex with men(MSM)aged 16–24 years in China.This population exhibits a disproportionately high burden of HIV,with only 51.6%of HIV cases previously diagnosed.What are the implications for public health practice?HIV services should be expanded to include these key populations.Tailored interventions are needed to remove barriers to regular HIV services faced by young key populations.

关键词： prevention remove expanded