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The weakening effect of urbanization on tropical cyclone surface winds:An observational study for Shanghai

Tropical Cyclone Research and Review 2024年第1期13卷 15-23页

作者： Lechuan zhang Hui Yu Xiangyu ao Shengming Tang Chinese Academy of Meteorological Sciences BeijingChina Shanghai Typhoon Institute China Meteorological AdministrationShanghaiChina

The observation-reanalysis difference method(OMR)and wind proﬁleﬁtting method were used to analyze the inﬂuence urbanization has on the near-surface wind speed in Shanghai during tropical cyclone *** data used include daily wind speed data from the Shanghai Meteorological Observatory Station collected from 1991 to 2020,hourly wind speed data from 100 m high wind towers from 2017 to 2019,and reanalysis data that covered the same *** results indicated that during tropical cyclone occurrence,the wind speed of the OMR in the central urban region was signiﬁcantly lower than that in the suburban area,and the OMR declined more obviously over the year,down to-8 m/s in *** leads to the increase of average wind weakening rate to be higher than the maximum wind weakening rate,causing the maximum weakening rate of the central urban region to the average wind over 80%,while maximum wind speed was less than 80%.The weakening rate of both the average and maximum wind speeds during tropical cyclone impacts is greater than the rate that the annual average wind speed was reduced.A logarithmic variation was visible in the wind proﬁle of the island station during tropical cyclone occurrence,with an average friction velocity U*of 0.9389 m/s and an average rough length z0 of 0.4915 *** wind speed during tropical cyclone events was higher than the three-year average wind speed within each *** suburban stations show a linear variation,and every hundred meters of height results in an increase of 5–6 m/s in the wind speed change *** 100 m of altitude,the wind speed in the suburban region is reduced by approximately 40%.

关键词： Urbanization Tropical cyclone Shanghai Wind speed

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Protective effects of baffles with different positions,row spacings,heights on debris flow impact

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Journal of Mountain Science 2024年第7期21卷 2352-2367页

作者： SUN Xinpo CHEN Min BI Yuzhang zHENG Lu CHE Chi XU ao TIAN zijian JIANG zheyuan College of Civil Engineering Sichuan University of Science and EngineeringZigong 643000China College of Resources and Environment Fujian Agriculture and Forestry UniversityFuzhou 350002China School of Civil Engineering Fuzhou UniversityFuzhou 350108China Jiangsu Key Laboratory of Urban Underground Engineering&Environmental Safety Institute of Geotechnical EngineeringSoutheast UniversityNanjing 210096China Beijing Urban Construction Science Technology Promoting Association Beijing 100055China SUSE-Bz Geoenvironmental Engineering Joint Laboratory Sichuan University of Science and EngineeringZigong 643000China

The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow ***,they are widely used for protection against natural hazards such as landslides and *** study,based on the threedimensional DEM(Discrete Element Method),investigated the impact of different baffle positions on debris flow *** flow velocity and kinetic energy variations were studied through single-factor *** baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris ***,based on the selected baffle positions and four factors influencing the effectiveness of baffle protection(baffle position(P),baffle height(h),row spacing(S_(r)),and angle of transit area(α)),an orthogonal design was employed to further explore the optimal arrangement of *** research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their *** the baffle is placed in the transit area,the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition ***,when the baffle is placed in the transit area,the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition *** orthogonal experimental range analysis,when the impact on the first row of baffles is used as the evaluation criterion,the importance of each influencing factor is ranked asα>P>S_(r)>*** the mass of debris flow behind the baffle is regarded as the evaluation criterion,the rank is changed to P>α>S_(r)>*** experimental simulation results show that the optimal baffle arrangement is:P_(5),S_(r)=16,α=35°,h=9.

关键词： Debris flow Baffle Protective effect Discrete element

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Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.F.zhang H.Q.Ye z.Q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

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Hierarchical CoFe@N-Doped Carbon Decorated Wood Carbon as Bifunctional Cathode in Wearable zn-Air Battery

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Energy & Environmental Materials 2024年第1期7卷 42-50页

作者： Kelong ao Xiangyang zhang Renat R.Nazmutdinov Di Wang Jihong Shi Xian Yue Jianguo Sun Wolfgang Schmickler Walid A.Daoud Department of Mechanical Engineering City University of Hong KongHong Kong 999077China Kazan National Research Technological University 420015 KazanRussian Federation School of Textile and Garment Anhui Polytechnic UniversityWuhu 241000China Wood Materials Science Institute for Building MaterialsETH Zürich8093 ZürichSwitzerland Am Sandhaken 18 D-89069 UlmGermany

Rechargeable zn-air batteries(zAB)have drawn extensive attention due to their eco-friendliness and ***,the lack of high-performance and low-cost oxygen redox reactions(OER and ORR)catalysts has become one of the main stumbling blocks in their ***,we successfully fabricate a CoFe nanobubble encapsulated in nitrogen-doped carbon nanocage on wood carbon support(CoFe@NC/WC)via pyrolysis of a novel Prussian blue analog(PBA)/spruce *** hierarchical CoFe@NC/WC catalyst exhibits an excellent potential difference of 0.74 V between the OER potential at 10 mA cm^(-2)and half-wave potential of ORR in 0.1 M KOH,comparable to recently reported preeminent ***,CoFe@NC/WC shows outstanding electrochemical performance in liquid zAB,with a peak power density of 138.9 mW cm^(-2)and a specific capacity of 763.5 mAh g^(-1).More importantly,a bacterial cellulose nanofiber reinforced polyacrylic acid(BC-PAA)hydrogel electrolyte shows ultrahigh tensile-breaking stress of 1.58 *** conjunction with the as-prepared CoFe@NC/WC catalyst,BC-PAA-based wearable zAB displays impressive rechargeability and foldability,and can power portable electronics,such as electronic timer and mobile phone,in bent *** work provides a new approach toward high-activity and low-cost catalysts for zAB.

关键词： biomass-based catalyst DFT computation hydrogel electrolyte oxygen redox reactions wearable zn-air battery

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Chinese Population Reference Curves for Ultrasound-Measured Amniotic Fluid Deepest Vertical Pocket in Dichorionic Twin Pregnancies,and Their Associations With Pregnancy Outcomes

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Maternal-Fetal Medicine 2024年第1期6卷 29-36页

作者： zhengxin Lyu Tianchen Wu Shan Lu Pengbo Yuan yangyu z.ao Yuan Wei Department of Obstetrics and Gynecology Peking University Third HospitalBeijing 100191China

Objective:To establish the Chinese population's amniotic fluid deepest vertical pocket(DVP)reference curves for dichorionic twin pregnancies and to investigate DVP links with adverse perinatal ***:This retrospective cohort study,conducted at Peking University Third Hospital from August 2011 to December 2020,used data from 375 women aged 20 to 45 years who had dichorionic twin pregnancies that were confirmed through first-trimester *** exclusions,reference curves were developed using 318 women with 3,299 DVP scans,and the data analyzed included maternal demographics,pregnancy outcomes,ultrasound measurements,and neonatal *** were assessed via ultrasound at regular intervals and grouped by gestational age(GA)for *** mixed models were used to create amniotic fluid reference *** between abnormalities and adverse perinatal outcomes were examined using Chi-squared or Fisher's exact *** regression provided both crude and adjusted odds ratios,adjusting for pre-pregnancy weight,age,ethnicity,parity,and conception *** was set at P<0.05 with 95%confidence intervals(CI),and the analyses were conducted using SPSS ver.26.0(IBM Corp.,Armonk,NY)and SAS ver.9.4(SAS Institute Inc.,Cary,NC,USA)***:DVP increased from the first trimester to a maximum at 26 weeks(95%confidence interval(CI),2.7–8.3 cm for twin 1 and 2.8–7.9 cm for twin 2)and then decreased gradually toward *** between twins 1 and 2 were significant after 26 weeks(95%CI for twin 1:5.3,5.5;95%CI for twin 2:4.4,4.5;P<0.010).Polyhydramnios of twin 1 increased the risk of large for *** of twin 1 increased the risk of small for *** of twin 2 increased the risk of small for GA,premature birth,and neonatal *** of twin 2 increased the risk of preeclampsia,hypertensive disorder complicating pregnancy,and premature rupture of ***:Reference curves

关键词： Amniotic fluid Amniotic fluid deepest vertical pocket Reference curve Dichorionic twin Pregnancy outcome Ultrasound examination

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On power series statistical convergence and new uniform integrability of double sequences

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 519-532页

作者： Sevda Y■ld■z Kamil Demirci Sinop University Department of MathematicsSinopTurkey

In the present paper,we mostly focus on P_(p)^(2)-statistical *** will look into the uniform integrability via the power series method and its characterizations for double ***,the notions of P_(p)^(2)-statistically Cauchy sequence,P_(p)^(2)-statistical boundedness and core for double sequences will be described in addition to these findings.

关键词： power series methods statistical convergence uniform integrability double sequences

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Rational design of AgGaS/znS/znS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu z.z.Fu Y.Y.Chen H.Q.Dai z.Hu W.L.zhang R.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/znS/znS quantum dots(QDs).In the first step,an inner znS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer znS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/znS/znS QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS ***,the effect of halogen ions in zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between zn cation diffusion and znS shelling ***,the znS shelling reaction was dominant when znCl_(2)was employed,while zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the znS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

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Importance of diet and intestinal microbiota in the prevention of colorectal cancer-colonoscopy early screening diagnosis

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3428-3435页

作者： Miljana z Jovandaric Department of Neonatology Clinic for Gynecology and ObstetricsUniversity Clinical Center of SerbiaBelgrade 11070Serbia

Colorectal cancer is a term used to describe colon and rectal cancer,which is the third most common type of cancer.A MEDLINE and PubMed search resulted in the inclusion of manuscripts written in the last 10 years,using keywords relevant to the topic of the *** analyzing the aim of the searched studies and manuscripts,adequate articles were included that described the stated *** frequency of colorectal cancer varies with climate,nutrition,and many other factors,primarily endogenous,hereditary,intestinal microbiome,as well as external factors,such as exposure of the individual to stress,and bad eating *** cancer and rectal cancer or colorectal cancer in general in the early stages of the disease,may not show symptoms or are barely *** cancer symptoms will most often not develop until the disease has progressed to stage 2 or *** screening tests for colon or rectal cancer,especially colonoscopy,are recommended as part of a regular checkup for people aged 50 years or younger who are at high risk due to a family history of the disease or other *** and colonoscopy as an early screening method play an important role in the prevention of colorectal cancer.

关键词： Colorectal cancer Causes Symptoms Screening Diet and colonoscopy

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Effects of multiple shapes for steady flow with transformer oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 373-388页

作者： M.RAHMAN M.TURKYILMAzOGLU z.MUSHTAQ Department of Mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan Department of Mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity *** system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c MATLAB *** outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower *** the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom *** ranges of various parameters taken into account are Pr=6.2,Re=2,M=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number

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Four Late-type Galaxies with Double Radio Lobes and Properties of Such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： z.S.Yuan X.Y.Gao z.L.Wen J.L.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** samples are desired for a thorough investigation and *** utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRao VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four Late-type Galaxies with double Radio Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously known La GRLs,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)La GRLs belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of La GRLs are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

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