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Smoke and NO_(x)emission characteristics of in-use construction machinery base on substantial field measurement:A case study in Beijing,China

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Journal of Environmental Sciences 2025年第3期149卷 386-393页

作者： Huawei Yi yangyang Cui Lijun Zhu yan Shen han Li Guanghan Huang Linzhen Qu Dongdong guo Lei Nie Yifeng Xue National Engineering Research Center of Urban Environmental Pollution Control Beijing Municipal Research Institute of Eco-Environmental ProtectionBeijing 100037China Beijing Vehicle Emission Management Affairs Centre Beijing 100176China

To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NO_(x).The exhaust smoke level and excessive emission situation of different machinery types were identified,and their NO_(x)emission levels were monitored according to the free acceleration *** investigated the correlation of NO_(x)and smoke emission,and proposed suggestions for controlling pollution discharge from construction machinery in the *** results show that the exhaust smoke level was 0–2.62 m^(−1),followed a log-normal distribution(μ=-1.73,δ=1.09,R^(2)=0.99),with a 5.64%exceedance *** observed amongmachinery types,with low-power engine forklifts showing higher smoke *** NO_(x)emission range was 71–1516 ppm,followed a normal distribution(μ=565.54,δ=309.51,R^(2)=0.83).Differences among machinery types were relatively *** rated net power had the most significant impact on NO_(x)***,NO_(x)emissions from construction machinery need further ***,we found a weak negative correlation(p<0.05)between the emission level of smoke and NO_(x),that is the synergic emission reduction effect is poor,emphasizing the need for NO_(x)emission *** the future,the oversight in Beijing should prioritize phasing out ChinaⅠand ChinaⅡmachinery,and monitor emissions from highpower engine ChinaⅢmachinery.

关键词： Fuel-oil construction machinery Smoke NO_(x) Emission level Regulatory suggestion

Frog tongue-inspired wettable microfibers for particles capture

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Science Bulletin 2025年第3期70卷 383-389页

作者： Jiahui guo Lingyu Sun han Zhang Yuanjin Zhao Department of Rheumatology and Immunology Nanjing Drum Tower HospitalSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China Shenzhen Research Institute Southeast UniversityShenzhen 518071China Chemistry and Biomedicine Innovation Center ChemBioMed Interdisciplinary Research CenterNanjing UniversityNanjing 210023China

Fibers have been of great significance in our daily lives,especially in the industrial production of *** in this area has been focused on developing microfibers with superior functions to enhance the filtration performances of the ***,inspired by the frog’s predation mechanism using its tongues to swiftly grab flying insects,we propose novel porous wettable microfibers from microfluidics to efficiently capture particles in the air for *** pre-dispersing LP emulsions into polyurethane(PU),porous microfibers dispersed with oil droplets could be continuously spun from a co-flow microfluidic device based on the quick phase inversion of *** design an optimal system with frog-tongue-like interfacial adhesion properties,the wettability performances of the porous microfibers are investigated under full,partial,and no oil coverage *** implemented in a mask,the 3D patterned networks based on the frog-tongue-inspired microfibers have been proven with remarkable particle capture performances while maintaining good air *** on these features,we believe that frog-tongue-inspired microfibers and their derived masks are of practical significance in multiple applications.

关键词： Bioinspired Microfluidics Microfiber Wettability Mask

Gradient age-precipitation behavior induced by gradient nano-grain in Mg-Gd-Ag-Zr alloy

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Journal of Iron and Steel Research International 2025年第1期32卷 19-24页

作者： Bang-jun Li Jia-peng Sun Jing han guo-song Wu College of Materials Science and Engineering Hohai UniversityNanjing 210024JiangsuChina School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116JiangsuChina

Gradient nano-grained structure is frequently engineered into metallic materials,including Mg alloys,to achieve superior combination of strength and ***,the influence of this microstructural feature on aging precipitation behavior remains inadequately *** this study,the age-precipitation behavior of a gradient nano-grained Mg-Gd-Ag-Zr alloy prepared via ultrasonic severe surface rolling was *** result indicates that the aging precipitation behavior exhibits a depth-dependent variation within this *** the nano-grained surface layer,hierarchicalβnano-precipitates are predominant,while at greater depths,the precipitates consist ofβnanoparticles located at grain boundaries,along with intragranularβ′andγ″*** formation ofβnano-precipitates deviates from the conventional precipitation behavior observed in Mg-Gd-Ag alloys,and is attributed to the high density of defects induced by the surface nano-grained *** finding advances our understanding of the precipitation behavior in the alloys with heterogeneous microstructure.

关键词： Mg alloy Gradient Precipitation Aging behavior Microstructure

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao Li yangfei Chen yang Jiang Xiaofei guo han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

The detection,extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 82-92页

作者： Qianyun Yun Wen-Biao han Yi-yang guo He Wang Minghui Du hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310124China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Taiji Laboratory for Gravitational Wave Universe(Beijing/hangzhou) University of Chinese Academy of SciencesBeijing 100049China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceKey Laboratory of Quantum Theory and Applications of MoELanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China International Centre for Theoretical Physics Asia-Pacific(ICTP-AP) University of Chinese Academy of Sciences(UCAS)Beijing 100049China Center for Gravitational Wave Experiment National Microgravity LaboratoryInstitute of MechanicsChinese Academy of SciencesBeijing 100190China

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EM-RIs).This task is particularly challenging because EMRI signals are complex,lengthy,and *** this work,we introduce a 2-layer convolutional neural network(CNN)approach to detect EMRI signals for space-borne detectors,achieving a true positive rate(TPR)of 96.9%at a 1%false positive rate(FPR)for signal-to-noise ratio(SNR)from 50 to ***,the key intrinsic parameters of EMRIs such as the mass,spin of the supermassive black hole(SMBH)and the initial eccentricity of the orbit can also be inferred directly by employing a neural *** mass and spin of the SMBH can be determined at 99%and 92%*** will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform *** study underscores the potential of deep learning methods in EMRI data analysis,enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

Metrological traceable calibration of organic carbon and elemental carbon based on laboratory-generated reference materials

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Journal of Environmental Sciences 2025年第3期149卷 524-534页

作者： Yue Liu Junjie Liu Ji Xiao Jing Ye Lixu guo Caiqing yan Center for Environmental Metrology National Institute of Metrology ChinaBeijing 100029China College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China Environment Research Institute Shandong UniversityQingdao 266237China

Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate *** measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source *** accurate separation of OC and EC is controversial due to the charring of ***,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further *** RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC *** develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz *** generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC *** RMs were analyzed using different *** homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol ***,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.

关键词： Carbonaceous aerosol Split point Reference material Laboratory-generated Traceability

Artificial intelligence advances drug delivery system and its clinical transition

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Science Bulletin 2025年第3期70卷 305-308页

作者： Hui Wang Xiao-yan You guo-Ping Zhao Master Lab for Innovative Application of Nature Products National Center of Technology Innovation for Synthetic BiologyTianjin Institute of Industrial BiotechnologyChinese Academy of Sciences(CAS)Tianjin 300308China Henan Engineering Research Center of Food Microbiology College of Food and BioengineeringHenan University of Science and TechnologyLuoyang 471023China Haihe Laboratory of Synthetic Biology Tianjin 300308China CAS-Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China CAS Key Laboratory of Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Since November 2022,ChatGPT,an artificial intelligence(AI)chatbot,has rapidly captured global attention for its detailed responses and articulated answers across a broad spectrum of knowledge domains[1],[2].All industries will reorient around it,prompting a reevaluation of how this technology could further promote scientifical research and its clinical applications.

关键词： system transition spectrum

Stress anisotropy regulated wrinkling pattern evolution on a core-shell soft cylinder

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 132-144页

作者： yan Zhao Zhipan Jie Yilong Zhang guo-yang Li yanping Cao Chao Jiang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China Institute of Biomechanics and Medical Engineering AMLDepartment of Engineering MechanicsTsinghua UniversityBeijing100084China

Diverse wrinkling patterns can occur on curved bilayer systems under differential growth or *** such systems,stress anisotropy is frequently encountered,and the coupling effect of curvature and stress anisotropy on the pattern evolution remains largely *** this study,we investigate the evolution of wrinkling patterns on a cylinder core-shell system with stress anisotropy leveraging both theoretical analysis and finite element *** buckling analysis has identified three distinct critical buckling modes regulated by the stress anisotropy,i.e.,axial sinusoidal mode,checkerboard mode,and circumferential sinusoidal *** finite element simulations,along with post-buckling analysis,reveal seven distinct evolutionary paths stemming from the three critical buckling *** present phase diagrams for both the critical buckling modes and their evolutionary paths,which are determined by dimensionless curvature and stress *** results not only expand the theoretical research on surface wrinkling of a core-shell soft cylinder but also introduce stress anisotropy as a significant parameter for regulating the wrinkling patterns and their evolutionary paths in curved bilayer *** revelation of a multitude of wrinkling patterns and their evolutionary pathways holds great potential for advancing applications that leverage tunable wrinkle surfaces.

关键词： wrinkling pattern evolutionary path stress anisotropy dimensionless curvature core-shell soft cylinder

Femtosecond mode-locking and soliton molecule generation based on a GaAs saturable absorber

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Chinese Physics B 2025年第1期34卷 344-349页

作者： Chen-yan Zhang Xin-He Dou Zhen Chen Jing-han Zhao Wei Sun Ze-Yu Fan Tao Zhang Hao Teng Zhi-guo Lv School of Physical Science and Technology Inner Mongolia UniversityHohhot 010021China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

In the last few years,research on advanced ultrafast photonic devices has attracted great interest from laser *** a semiconductor material with excellent nonlinear saturation absorption characteristics,Ga As has been used in solidstate and fiber lasers as a ***,the pulse widths that have been reported in the searchable published literature are all long and the shortest is tens of *** pulse widths,desired for a variety of applications,have not yet been reported in Ga As-based pulsed *** this work,we further explore the nonlinear characteristics of Ga As that has been magnetron sputtered onto the surface of a tapered fiber and its application in the generation of femtosecond lasing via effective dispersion optimization and nonlinearity *** the enhanced interaction between evanescent waves and Ga As nanosheets,mode-locked soliton pulses as short as 830 fs are generated at repetition rates of 4.64 *** far as we know,this is the first time that femtosecond-level pulses have been generated with a Ga As-based saturable *** addition,soliton molecules,including in the dual-pulse state,are also realized under stronger *** work demonstrates that Ga As-based photonic devices have good application prospects in effective polymorphous ultrashort pulsed laser generation.

关键词： GaAs saturable absorber mode-locking soliton molecule