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Ch.racterization and source apportionment of volatile organic compounds in h.ng kong:A 5-year study for th.ee different arch.typical sites

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Journal of Environmental Sciences 2025年第5期151卷 424-440页

作者： Yuch.n Mai Vincent Ch.ung Peter k.k.Louie kenneth.Leung Jimmy C.h.Fung Alexis k.h.Lau Donald R.B.lake Dasa Gu Division of Environment and Sustainability The Hong Kong University of Science and TechnologyHong Kong 999077China Environmental Protection Department Hong Kong 999077China Environment and Ecology Bureau Hong Kong 999077China Department of Ch.mistry University of CaliforniaIrvine 92617USA

Initial success h.s been ach.eved in h.ng kong in controlling primary air pollutants,but ambient ozone levels kept increasing during th. past th.ee *** organic compounds(VOCs)are important for mitigating ozone pollution as its major *** study analyzed VOC ch.racteristics of roadside,suburban,and rural sites in h.ng kong to investigate th.ir compositions,concentrations,and source *** sh.wth.t th. TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,*** using Positive Matrix Factorization(PMF)model,six sources were identified at th. roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exh.ust(5%–16%),diesel exh.ust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguish.d at th. suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exh.ust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At th. rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),veh.cular emissions(11%–28%),and biogenic emissions(6%–12%).Th. analysis furth.r revealed th.t fuel filling and LPG usage were th. primary contributors to OFP and Oh.reactivity at th. roadside site,wh.le solvent usage and biogenic emissions accounted for almost h.lf of OFP and Oh.reactivity at th. suburban and rural sites,*** findings h.gh.igh. th. importance of identifying and ch.racterizing VOC sources at different sites to h.lp policymakers develop targeted measures for pollution mitigation in specific areas.

关键词： Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation

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Zeros of th. Eta and Zeta Functions

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Journal of Applied Math.matics and Ph.sics 2025年第1期13卷 256-266页

作者： Joh. h. h.inbockel Independent Research.r Virginia Beach Virginia USA

Th. eta function is examined over th. critical strip 0σ1and th.re is an investigation of th. statement th.t all zeros of th. zeta function must lie on th. critical line Re(s)=1/2. A furth.r investigation is made into... 详细信息

关键词： Riemann h.poth.sis Zeta Function Zeros Dirich.et Eta Function Zeros

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Continuously adjustable mech.nical metamaterial based on planetary gear trains and external mesh.ng gears

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Applied Math.matics and Mech.nics(English.Edition) 2025年第2期46卷 233-252页

作者： Sh.ai MO Xu TANG keren Ch.N h. h.UJOh.Wei Zh.NG State key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures School of Mechanical Engineering Guangxi University State key Laboratory of Precision Manufacturing for Extreme Service Performance Central South University State key Laboratory of Digital Manufacturing Equipment and Tech.ology Huazhong University of Science and Technology Precision and Intelligence Laboratory Tokyo Institute of Technology

Th. metamaterial based on external mesh.ng gears(MEG) is designed based on th. principle of external mesh.ng gear transmission. Based on th. mesh.ng transmission principle of external mesh.ng gears and planetary gear trains, th. internal and external gear rings are designed. Based on th. internal and external gear rings, th. metamaterial based on inner and outer planetary gear trains(MIP) is designed to study th. sh.ar modulus, Young's modulus, and amplitude-frequency ch.racteristics of th. metamaterial based on gears at different angles. Th. effects of th. number of planetary gears on th. ph.sical ch.racteristics of th. MIP are studied. Th. results sh.w th.t th. MEG can be continuously adjusted by adjusting th. sh.ar modulus and Young's modulus due to its mesh.ng ch.racteristics. With.th. same number of gears, th. adjustment range of th. MIP is larger th.n th. adjustment range of th. MEG. Wh.n th. number of planetary gears increases, th. adjustment range of th. MIP decreases. Moreover, wh.n th. metamaterial based on gears rotates, th. h.rmonic response ch.nges with.th. ch.nge of th. angle.

关键词： metamaterial adjustable external inner and outer planetary gear train TB34

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电子血糖分析仪用于新生儿低血糖床旁测定可能不十分可靠

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世界核心医学期刊文摘（儿科学分册） 2006年第6期2卷 19-19页

作者： Rosenth.l M. Ugele B. Lipowsky G. küster h. 刘莉 Department for Neonatology and Pediatric Intensive Care University Children's Hospital Soldtmannstr. 15 17487 Greifswald Germany

Th. aim of th.s prospective observational study was to compare a bedside test with.th. reference laboratory meth.d in routine postnatal glucose monitoring. Term newborns with.increased risk or clinical signs of h.poglycemia were screened with.a bedside test. In case of a glucose value below 2.25 mmolL, a second blood sample was taken and a duplicate glucose measurement done in th. laboratory using a bedside test (Accutrend sensor) and th. reference laboratorymeth.d (h.xokinase meth.d) at th. same time and from th. same sample. From 110 term newborns, 122 blood samples were obtained for duplicate measurements (median 1.69 mmolL, SD 0.45 mmolL). Of th.se 122, Accutrend correctly identified 97%as being h. laboratory meth.d. A Bland-Altman plot revealed a mean underestimation of th. Accutrend of only-0.09 mmolL. h.wever, due to h.gh.scattering, th. maximal over-and underestimation was 0.89 and 1.39 mmolL, respectively. Only 75%of th. results from th. Accutrend were with.n ±20%of th. result of th. laboratory meth.d. If th. cutoff for low glucose concentrations was set 0.6 mmolL h.gh.r for th. bedside test as compared to th. laboratory meth.d, all patients except one would h.ve been correctly identified as h.poglycemic. Conclusion: Wh.n using th. Accutrend sensor, single infants with.even marked h.poglycemia migh. be missed. Some delay in receiving accurate measurements migh. be more h.lpful for clinical decisions and long-term outcome th.n immediate but potentially misleading results.

关键词：新生儿低血糖血糖测定值床旁检测分析仪 0.6mmol/L 电子实验室方法实验室检查方法足月新生儿前瞻性观察

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Ph.toluminescence upgradation of La_(2)MgTiO_(6):2%Dy^(3+) perovskite with.monovalent(Li^(+)),divalent(Ba^(2+),Sr^(2+)) and trivalent(Bi^(3+),Sm^(3+))cation sensitization

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Journal of Rare Earth. 2025年第1期43卷 47-56,I0002页

作者： V.P.Veena k.Arun C.k.Sh.lpa S.V.Jasira k.M.Nissamudeen Sch.ol of Pure and Applied Ph.sics Kannur UniversityPayyanur CampusEdatKannurKrala67 India Department of Nanoscience and Nanotech.ology Kannur UniversityPayyanur CampusEdatkannurKerala670327India

Nano ph.sph.rs of 2%Dy^(3+)(wt%)doped La_(2)MgTiO_(6) and monovalent/divalent/trivalent co-doped La_(1.98)Dy_(0.02)MgTiO_(6):x%A^(y+)(A^(y+):Li+,Ba^(2+),Sr^(2+),Bi^(3+),and Sm^(3+);0≤x≤2 wt%)were synth.sized by combustion *** th. XRD data,it is deduced th.t an increase in th. valency of co-dopant increases th. crystallinity of th. double perovskite orth.rh.mbic nanocrystal *** an increase in co-dopant size,an elevation in optical bandgap is visible with.th. h.gh.st bandgap of 3.835 eV for Bi^(3+).Th. ph.to-absorption is monotonically broadened for Sr^(2+),Sm^(3+),and Li+around 200-450 ***351 nm,Dy^(3+)triggered lattice sh.ws major ch.racteristic emission peaks at 480 nm(^(4)F_(9/2)→^(6)h.(15/2)),574 nm(^(4)F_(9/2)→^(6)h.(13/2)),and 670 nm(^(4)F_(9/2)→^(6)h.(11/2)).leading to near wh.te ligh. emission with.CIE coordinates(0.341,0.376).Upon co-doping,th. PL intensity is significantly increased with.maximum emission for trivalent Sm^(3+),followed by divalent Sr^(2+)and monovalent Li+*** increasing excitation wavelength.Sr^(2+)sh.ws a dominated output and it is found th.t divalent Sr^(2+)is a potential codopant th.t could enh.nce luminescence intensity up to 6 times with.a Sr^(2+)→Dy^(3+)energy transfer efficiency of 86%.It is specified th.t th. CIE coordinates of Li+co-doped samples sh.w ideal wh.te emission with.color coordinates(0.333,0.336).Th. concluding outcomes signify th. noblest rare earth.Sm^(3+)co-doping and th.s Sm^(3+)→Dy^(3+)energy transfer mech.nism is discussed in detail.

关键词： Ph.toluminescence Perovskite WLED Co-doping Rareearth.

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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point sph.rical source embedded with.n a fluid-saturated poroelastic formation of infinite extent

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Applied Math.matics and Mech.nics(English.Edition) 2025年第1期46卷 139-156页

作者： h.h.SSEINI O.BALILASh.kI Department of Mech.nical Engineering Faculty of EngineeringGolestan University

Th. effects of a h.rmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely with.n a fluid-saturated poroelastic formation of infinite extent are examined th.oretically. It is assumed th.t th. source is located outside th. cavity at a specified distance from th. boreh.le axis. Th. magnitudes of th. h.op and radial stresses beside th. pore pressures exerted on th. interface and inside th. porous medium surrounding th. boreh.le are calculated and discussed. Biot's poroelastic modeling along with.th.ee types of boundary conditions for th. cylindrical interface including th. ideal fluid, empty boreh.le, and rigid inclusion with.a h.rd boundary is employed for th. analysis. Utilizing a proper translational addition th.orem for expressing th. incident sph.rical wave in terms of cylindrical wave expansions, th. proposed boundary conditions at th. interface are satisfied. Stresses are formulated by means of wave potential functions in a th.ee-dimensional(3D) manner. Th. effects of th. frequency and th. radial distance between th. source and boreh.le on th. induced stresses are examined for th. first cylindrical modes over frequency spectra. Two permeability conditions for th. interface and th.ee types of soils for th. porous formation are considered th.ough.ut th. analysis. To give an overall outline of th. study, a numerical example is presented. Th. results clearly indicate th.t th. distance is a key parameter and h.s considerable effects on th. induced stress values. In addition, th. interface permeability condition and soil ch.racteristics play an important role in determining th. dynamic response of th. boreh.le. Finally,th. obtained results are compared with.th. relevant analyses existing in th. literature for some limit cases, and good agreement is ach.eved.

关键词： cylindrical cavity O353.4 point source porous medium stress concentration wave-field transformation

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Ch.racteristics of Energy Fluxes and Cold Frontal Effects on Energy Exch.nge over a Boreal Lake

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Advances in Atmosph.ric Sciences 2025年第2期42卷 357-372页

作者： Lujun XU h.izh. LIU Ivan MAMMARELLA Aki VÄh. Joonatan ALA-kÖNNI Xuefei LI Qun DU Yang LIU Timo VESALA State key Laboratory of Atmosph.ric Boundary Layer Ph.sics and Atmosph.ric Ch.mistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Ch.nese Academy of Sciences Beijing 100864China Department of Atmosph.ric Sciences Yunnan UniversityKunming 650091China Institute for Atmosph.ric and Earth.System Research.Ph.sics Faculty of ScienceUniversity of HelsinkiHelsinki 00014Finland

Understanding th. ch.racteristics and variations of h.at exch.nge and evaporation of lakes is important for regional water resource management and sustainable *** on eddy covariance measurements over Lake Vanajavesi in south.rn Finland,ch.racteristics of energy fluxes and cold frontal effects on energy exch.nge were *** lake acted as a h.at sink in spring and summer and a h.at source in *** latent h.at flux reach.d its minimum value in th. morning and peaked in th. *** diurnal variation of sensible h.at flux was opposite to th.t of latent h.at *** factors for th. sensible h.at flux were mainly th. lake-air temperature difference and th. product of lake-air temperature difference and wind *** latent h.at flux was mainly affected by th. vapor pressure deficit and th. product of vapor pressure deficit and wind *** annual mean values of bulk transfer coefficients for momentum,h.at,and water vapor were 1.98×10^(-3),1.62×10^(-3),and 1.31×10^(-3),*** transfer coefficients for h.at and water vapor were not equal,indicating th.t th. parameterization of energy exch.nge in numerical models,wh.re th. assumption th.t th. h.at coefficient equals th. water vapor coefficient needs *** th. ice-free season,cold fronts resulted in 28 sensible h.at pulses and 17 latent h.at pulses,contributing to 50.59%and 34.89%of sensible and latent h.at exch.nge in Lake *** results indicate th.t cold fronts significantly impact th. surface energy budget and evaporation over lakes.

关键词： sensible h.at flux latent h.at flux rough.ess length bulk transfer coefficient cold front

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Finite cell meth.d compared to h.version finite element meth.d for elasto-plastic problems

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Applied Math.matics and Mech.nics(English.Edition) 2014年第10期35卷 1239-1248页

作者： A.ABEDIAN J.PARVIZIAN A.Dster E.RANk Department of Mech.nical Engineering Daneshpajoohan Higher Education Institute Department of Mech.nical Engineering Isfahan University of Technology Numerisch. Strukturanalyse mit Anwendungen in der Sch.ffstech.ik (M-10) Technische Universitt Hamburg-Harburg Leh.stuh. fr Computation in Engineering Fakultt fr Bauingenieur-und Vermessungswesen Technische Universitt Mnchen

Th. finite cell meth.d （FCM） combines th. h.gh.order finite element meth.d （FEM） with.th. fictitious domain approach.for th. purpose of simple mesh.ng. In th. present study, th. FCM is used to th. Prandtl-Reuss flow th.ory of plasticity, and th. results are compared with.th. h.version finite element meth.d （h.FEM）. Th. numerical results sh.w th.t th. FCM is more efficient compared to th. h.FEM for elasto-plastic problems, alth.ugh.th. mesh.does not conform to th. boundary. It is also demonstrated th.t th. FCM performs well for elasto-plastic loading and unloading.

关键词： finite cell meth.d (FCM) h.version finite element meth.d (h.FEM),Prandtl-Reuss quadtree octree

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h.gh.quality control of receiver functions using a capsule neural network

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Earth.uake Science 2025年第2期38卷 93-109页

作者： Mona h. h.gazi Ah.ad M. Faried Omar M. Saad National Research.Institute of Astronomy and Geoph.sics (NRIAG) Cairo 11421 Egypt Division of Ph.sical Science and Engineering King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia

Th. Red Sea-Gulf of Suez-Cairo-Alexandria Clysmic-Trend in north.rn Egypt is th. main earth.uake zone in th. country, with.a moderate-to-h.gh.seismic h.zard and a h.story of significant earth.uakes caused by rifting and active faulting. To improve our understanding of th. tectonic and seismic processes in th.s area, more compreh.nsive imaging of th. crustal structure is required. Th.s can be ach.eved by increasing th. number of receiver functions (RFs) recorded by th. seismic stations in north.rn Egypt and th. south.astern Mediterranean. Data h.ndling and processing sh.uld also be automated to increase process efficiency. In th.s study, we developed a capsule neural network for automated selection of RFs. Th. model was trained on a dataset containing RFs (both.selected and unselected) from five broadband stations in north.rn Egypt. Stations SLM, SIWA, kOT, NBNS, and NkL are located in th. unstable sh.lf region of Egypt, wh.re limited knowledge of th. deep crustal structure is available. Th. proposed capsule neural network ach.eved an average precision of 80% on th. test set. Th. automated selection of RFs using a capsule neural network h.s th. potential to significantly improve th. efficiency and accuracy of RF analysis, as demonstrated by th. stacking test. Th.s could lead to a better understanding of crustal structure and tectonic processes in north.rn Egypt and th. south.astern Mediterranean.

关键词： crustal structure receiver functions deep learning north.rn Egypt

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Evaluation of th. Effectiveness of Traditional and Nano Materials Used in Consolidation of Sandstone Used in Ramesses III Temple, karnak, Egypt

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Journal of Minerals and Materials Ch.racterization and Engineering 2025年第1期13卷 18-30页

作者： Essam h. Moh.med Zeinab Mah.oud Ah.ed Mah.oud L. Abd El-Latif Department of Arch.eological Conservation Faculty of Archaeology South Valley University Qena Egypt Department of Conservation Faculty of Archaeology South Valley University Qena Egypt h.using and Building Research.Center Giza Egypt

Th.s experimental study assesses th. effectiveness of traditional and nano-materials in enh.ncing th. ph.sical and mech.nical properties of deteriorated sandstone from Ramesses III Temple, karnak, Luxor, Egypt. Treatments included Nano Estel (5%), Paraloid B-72 (3%), Paraloid B-72/Nano Estel (3%/5%), and eth.l silicates. Treated samples underwent Scanning Electron Microscopy (SEM) and ph.sical/mech.nical testing. Results sh.w th.t Paraloid B-72/Nano Estel (3%/5%) yielded optimal consolidation, significantly improving sandstone’s ph.sical and mech.nical properties.

关键词： Ramesses III Temple Deteriorated Sandstone Consolidation Treatments Nano Material Ph.sical and Mech.nical Properties

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