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Infrared radiation characteristics of dagger-type hypersonic missile

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Chinese Journal of Aeronautics 2024年第4期37卷 137-150页

作者： Xubo DU Qingzhen YANG Haoqi YANG jin bai Yongqiang SHI School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China

Hypersonic vehicles emit strong infrared radiation from their high-temperature exhaust plume and body, which is critical for infrared early warning, tracking, and guidance. In this work, a comprehensive analysis is conducted on the factors involved in air dissociation reaction within the shock layer of hypersonic missile heads, as well as the multi-component afterburning effect of the exhaust plume. A novel Reverse Monte Carlo Method(RMCM) is proposed for infrared radiation calculation, which utilizes two-dimensional Low-Discrepancy Sequences(LDS) to improve computational accuracy. The numerical calculations for a dagger-type missile show that afterburning reactions increase the temperature on the centerline of the outlet exhaust plume by about 1000 K. The total infrared radiation intensity of the missile is the highest in the 1–3 μm band, with the hightemperature wall of the nozzle being the primary source of solid radiation, and gas radiation primarily coming from H_(2)O. The radiation intensity of the missile exhaust plume in the 3–5 μm band is the highest, with radiation sources primarily coming from CO_(2), CO, and HCl. Afterburning reactions of the exhaust plume increase the total infrared radiation intensity of the missile by about 0.7times. These results can provide reference for the detection and guidance of hypersonic missiles.

关键词： Hypersonic vehicles Infrared radiation Monte Carlo methods Low-discrepancy sequences Exhaust plume Afterburning

GEOSatDB:global civil earth observation satellite semantic database

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Big Earth Data 2024年第3期8卷 522-539页

作者： ming Lin Meng jin Juanzi Li Yuqi bai Department of Earth System Science Institute for Global Change StudiesMinistry of Education Ecological Field Station for East Asian Migratory BirdsTsinghua UniversityBeijingChina Department of Computer Science and Technology Tsinghua UniversityBeijingChina Tsinghua Urban Institute Tsinghua UniversityBeijingChina

Satellite remote sensing,characterized by extensive coverage,fre-quent revisits,and continuous monitoring,provides essential data support for addressing global *** the past six decades,thousands of Earth observation satellites and sensors have been deployed *** valuable Earth observation assets are contributed independently by various nations and organizations employing diverse *** poses a significant challenge in effectively discovering global Earth observation resources and realizing their full *** this paper,we describe the develop-ment of GEOSatDB,the most complete semantic database of civil Earth observation satellites developed based on a unified ontology model.A similarity matching method is used to integrate satellite information and a prompt strategy is used to extract unstructured sensor *** resulting semantic database contains 127,949 semantic statements for 2,340 remote sensing satellites and 1,021 observation *** global Earth observation capabil-ities of 195 countries worldwide have been analyzed in detail,and a concrete use case along with an associated query demonstration is *** database provides significant value in effectively facilitating the semantic understanding and sharing of Earth observa-tion resources.

关键词： Earth observation satellite sensor semantic representation information extraction

Data-driven surrogate model for aerodynamic design using separable shape tensor method

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Chinese Journal of Aeronautics 2024年第9期37卷 41-58页

作者： Bo PANG Yang ZHANG Junlin LI Xudong WANG min CHANG Junqiang bai State Key Laboratory for Srrenglh and Vibration of Mechanical Structures Xi'an Jiaotong UniversityXi'an 710049China Unmanned System Research Institute Northwestern Polytechmical UniversityXi'an 710072China

In the context of increasing dimensionality of design variables and the complexity of con-straints,the effcacy of Surrogate-Based Optimization(SBO)is *** traditional linear and nonlinear dimensionality reduction algorithms are mainly to decompose the mathematical matrix composed of design variables or objective functions in various forms,the smoothness of the design space cannot be guaranteed in the process,and additional constraint functions need to be added in the optimization,which increases the calculation *** study presents a new parameterization method to improve both problems of *** new parameterization is addressed by decoupling affine transformations(dilation,rotation,shearing,and translation)within the Grassmannian sub-manifold,which enables a separate representation of the physical information of the airfoil in a high-dimensional *** upon this,Principal Geodesic Analysis(PGA)is employed to achieve geometric control,compress the design space,reduce the number of design variables,reduce the dimensions of design variables and enhance predictive performance during the surrogate optimiza-tion *** comparison,a dimensionality reduction space is defined using 95%of the energy,and RAE 2822 for transonic conditions are used as *** method significantly enhances the optimization efficiency of the surrogate model while effectively enabling geometric *** three-dimensional problems,it enables simultaneous design of planar shapes for various components of the aircraft and high-order perturbation *** was applied to the ONERA M6 wing,achieving a lift-drag ratio of 18.09,representing a 27.25%improvement com-pared to the baseline *** comparison to conventional surrogate model optimization methods,which only achieved a 17.97%improvement,this approach demonstrates its superiority.

关键词： Aerodynamicdesign Grassmannian manifold Shape parameterization Surrogate-based optimiza-tion Data dimensionality reduction

Dietary fishmeal replacement by Clostridium autoethanogenum protein meal influences the nutritional and sensory quality of turbot(Scophthalmus maximus)via the TOR/AAR/AMPK pathways

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Animal Nutrition 2024年第3期18卷 84-95页

作者： Zezheng Qi Nan bai Qing Li Shihui Pan min Gu Marine College Shandong UniversityWeihaiShandongChina Key Laboratory of Modern Marine Ranching Technology of Weihai WeihaiShandongChina

Clostridium autoethanogenum protein(CAP)is a promising protein source for aquaculture;however,how CAP influences fish quality is worth extensive *** randomly allocated 630 turbot with initial body weights of about 180 g into 6 groups,with fishmeal-based control diet or diet with CAP replacing 15%(CAP15),30%(CAP30),45%(CAP45),60%(CAP60),or 75%(CAP75)of fishmeal *** a 70-d feeding trial,the fillet yield(P=0.015)and content of protein(P=0.017),collagen(P 0.05).By contrast,the muscle hardness increased linearly with increasing CAP(P=0.004),accompanied by linear reduction of muscle fiber area(P=0.003)and expression of myogenesis-related genes,including cathepsin D(ctsdPmino acid response(AAR)and AMPK pathways were ***,expression of genes related to protein degradation,including myogenic factor 5(myf 5,P<0.001),myogenic differentiation(myod,P<0.001),paired box 7(pax 7,P<0.001),and ctsd(P<0.001),decreased linearly with increasing *** conclusion,CAP could be used to replace up to 15%of fishmeal without negatively impacting turbot ***,higher levels of CAP decreased fillet yield,muscle protein content,and muscle fiber diameter while increasing muscle hardness,which could be attributed to the inhibition of the TOR pathway and activation of the AAR and AMPK pathways.

关键词： Bacterial meal Clostridium autoethanogenum Turbot Fish quality Muscle growth

Nanomaterial Assisted Exosome Analysis Using Mass Spectrometry

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Chemical Research in Chinese Universities 2024年第2期40卷 237-254页

作者： ZHANG Yi ZHOU Bokai LI Qiuning jin mingshi bai Yu Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871P.R.China Department of Chemistry Yanbian UniversityYanji133002P.R.China

Exosomes,extracellular vesicles(EVs)that play crucial roles in biological processes,have emerged as attractive targets for noninvasive disease diagnosis and *** spectrometry(MS)offers high sensitivity,high throughput,and excellent qualification and quantification capacity,which is the ideal approach for exosome ***’unique physiochemical properties,controllable morphology,and large surface area make them promising in biological sample pretreatment and *** contributed diverse functions to the exosome MS analysis,encompassing substrates for exosome isolation and cargos enrichment,matrices for laser desorption/ionization(LDI),read-out signals and supporters for signal amplification strategies,*** this review,recent progress in the applications of nanomaterial in the exosome MS analysis was summarized and a comprehensive discussion on the challenges and perspectives was proposed for the development of an advancing analysis approach of exosomes for the accurate diagnosis and monitoring of diseases.

关键词： Exosome Nanomaterial Enrichment Matrix Mass spectrometry

Construction of a High‑Performance Composite Solid Electrolyte Through In‑Situ Polymerization within a Self‑Supported Porous Garnet Framework

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Nano-Micro Letters 2024年第5期16卷 56-70页

作者： An‑Giang Nguyen min‑Ho Lee Jaekook Kim Chan‑jin Park Department of Materials Science and Engineering Chonnam National University77 Yongbong‑roBuk‑guGwangju 61186South Korea

Composite solid electrolytes(CSEs)have emerged as promising candidates for safe and high-energy–density solid-state lithium metal batteries(SSLMBs).However,concurrently achieving exceptional ionic conductivity and interface compatibility between the electrolyte and electrode presents a significant challenge in the development of high-performance CSEs for *** overcome these challenges,we present a method involving the in-situ polymerization of a monomer within a self-supported porous Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZT)to produce the *** synergy of the continuous conductive LLZT network,well-organized polymer,and their interface can enhance the ionic conductivity of the CSE at room ***,the in-situ polymerization process can also con-struct the integration and compatibility of the solid electrolyte–solid electrode *** synthesized CSE exhibited a high ionic conductivity of 1.117 mS cm^(-1),a significant lithium transference number of 0.627,and exhibited electrochemical stability up to 5.06 V ***/Li+at 30℃.Moreover,the Li|CSE|LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) cell delivered a discharge capacity of 105.1 mAh g^(-1) after 400 cycles at 0.5 C and 30℃,corresponding to a capacity retention of 61%.This methodology could be extended to a variety of ceramic,polymer electrolytes,or battery systems,thereby offering a viable strategy to improve the electrochemical properties of CSEs for high-energy–density SSLMBs.

关键词： Scalable tape-casting method Self-supported porous Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12) Composite solid electrolyte LiF-and B-rich interphase layers

Exploring the Interplay between Local Chain Structure and Stress Distribution in Polymer Networks

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Chinese Journal of Polymer Science 2024年第6期42卷 874-885页

作者： jin-Tong Xue Yang bai Li Peng Xian-Bo Huang Zhao-Yan Sun School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China National-certified Enterprise Technology Center Kingfa Science and Technology Co.Ltd.Guangzhou510663China

The mechanical behavior of polymer networks is intrinsically correlated with the local chain topology and chain *** this study,we delve into this relationship through the lens of coarse-grained molecular dynamics(CG-MD)*** aim is to illuminate the intricate interplay between local topology and stress distribution within polymer monomers,cross-linkers,and various components with distinct cross-link connections,thereby elucidating their collective impact on the mechanical properties of polymer *** mainly focus on how specific local structures contribute to the overall mechanical response of the *** particular,we employ local stress analysis to unravel the mechanics of these *** findings reveal the diverse responses of individual components,such as junctions,strands,cross-linkers between junctions,and dangling chain ends,when subjected to ***,we observe that these components exhibit varying degrees of deformation tolerance,underscoring the significance of their roles in determining the mechanical characteristics of the *** investigations highlight junctions as primary contributors to stress accumulation,and particles with higher local stress showing a stronger correlation between stress and Voronoi ***,our results indicate that both strands and cross-linkers between junctions exhibit heightened stress levels as strand lengths *** study enhances our understanding of the multifaceted factors governing the mechanical attributes of cross-linked polymer systems at the microstructural level.

关键词： Local chain structure Local stress Molecular dynamics simulation

Surface decoration of mesocarbon microbeads with multifunctional TiNbO_(4-x)@C coating layer as high rate and stable anode of Li-ion batteries

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Rare Metals 2024年第5期43卷 2053-2066页

作者： Jia-Mei Lai Zhi-min Zou Yu bai Yu-Tao Xing Chun-Hai Jiang Fujian Provincial Key Laboratory of Functional Materials and Applications Institute of Advanced Energy MaterialsSchool of Materials Science and EngineeringXiamen University of TechnologyXiamen 361024China Shanghai XFH Science and Technology Development Co. Ltd.Shanghai 200949China Fujian XFH New Energy Materials Co. Ltd.Yong'an 366000China Shenzhen XFH Science and Technology Co. Ltd.Shenzhen 518071China Laboratorio de Microscopia Eletronica de Alta Resolucao Centro de Caracterizagao Avangada Para a Industria de Petroleo(LaMAR/CAIPE)Universidade Federal FluminenseNiteroiRJ 24210-346Brazil

Surface modification of graphite anode with electroactive matters has been proven of a more practical strategy in enhancing the performance of Li-ion batteries than exploring alternative novel anode ***,rutile TiNbO_(4-x) nanoparticles with a tunnel structure are employed as multifunctional decoration substances in combination with a carbon coating layer to improve the rate and cycle properties of mesocarbon microbeads(MCMBs).As compared to pristine MCMB,the Li^(+)diffusion coefficients of the composite anodes are enhanced due to the synergistic effect of TiNbO_(4-x)@***,the overcharge and voltage polarization of the composite anodes at high rate are obviously minimized due to the current sharing effect of the high-potential TiNbO_(4-x).Moreover,the amorphous Li_(y)TiNbO_(4-x) converted from TiNbO_(4-x) in the initial lithiation process can deliver pseudocapacitive capacity to the composite anodes from the second *** of these functions of TiNbO_(4-x)@Ccoating layer have directly contributed to the improved rate and cycle performance of the MCMB/TiNbO_(4-x)@C composite *** one containing 12.0 wt%TiNbO_(4-x) exhibits a high reversible specific capacity of 118 m Ah·g^(-1)at 10C(1C=372 m A·g^(-1)),together with a high capacity retention of 90.9%after 300 cycles at 3C,which are all much superior to those of pristine MCMB.

关键词： Li-ion batteries MCMB TiNbO_(4-x)@C Surface decoration Rate capability

Five-year analysis of isolated pathogens and antibiotic resistance of ocular infections from two large tertiary comprehensive hospitals in east China

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1707-1716页

作者： Pan-Pan Li Li Li Jun-Fang Zhang bai Qin Li-Hua Kang min Ji Huai-jin Guan Suzhou Medical College of Soochow University Suzhou 215123Jiangsu ProvinceChina Department of Ophthalmology Affiliated Hospital of Nantong UniversityNantong 226001Jiangsu ProvinceChina Department of Clinical Laboratory Nantong City No.1 People’s Hospital and Second Affiliated Hospital of Nantong UniversityNantong 226001Jiangsu ProvinceChina

AIM:To analyze the spectrum of isolated pathogens and antibiotic resistance for ocular infections within 5y at two tertiary hospitals in east ***:Ocular specimen data were collected from January 2019 to October *** pathogen spectrum and positive culture rate for different infection location,such as keratitis,endophthalmitis,and periocular infections,along with antibiotic resistance were ***:We included 2727 specimens,including 827(30.33%)positive cultures.A total of 871 strains were isolated,530(60.85%)bacterial and 341(39.15%)fungal strains were ***-positive cocci(GPC)were the most common ocular *** most common bacterial isolates were Staphylococcus epidermidis(25.03%),Staphylococcus aureus(7.46%),Streptococcus pneumoniae(4.59%),Corynebacterium macginleyi(3.44%),and Pseudomonas aeruginosa(3.33%).The most common fungal genera were Fusarium spp.(12.74%),Aspergillus spp.(6.54%),and Scedosporium spp.(5.74%).Staphylococcus epidermidis strains showed more than 50%resistance to *** pneumoniae and Corynebacterium macginleyi showed more than 90%resistance to *** percentage of bacteria showing multidrug resistance(MDR)significantly decreased(χ^(2)=17.44,P=0.002).CONCLUSION:GPC are the most common ocular *** macginleyi,as the fourth common bacterium,may currently be the local microbiological feature of east *** *** the most common *** than 50%of the GPC are resistant to fluoroquinolones,penicillins,and ***,the proportion of MDR strains has been reduced over time.

关键词： ocular infections bacteria fungus antibiotic resistance multidrug resistance