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Journal of Ocean University of China 2024年第4期23卷 897-914页

作者： WANG Chaolin WU Guoxiang WANG d.anhe d. Shengtao z.ANG z.iyong JIN Heng z.U d.vid.z. LIANG Bingchen d.nghai Acad.my School of Civil&Environmental Engineering and Geography ScienceNingbo UniversityNingbo 315211China Key Laboratory of Estuary and.Coast of z.ejiang Province and Zhejiang Institute of Hydraulics and EstuaryHangzhou 310020China Shand.ng Provincial Key Laboratory of Ocean Engineering and College of EngineeringOcean University of ChinaQingdao 266100China Shand.ng Water Conservancy Vocational College Rizhao 276826China School of Mechanical and.Energy Engineering Ningbotech UniversityNingbo 315211China

Elucid.ting the flow features around.piles in local scouring processes is crucial for stud.es of local scouring mechanisms and.scour d.pth *** stud. d.tails the flow turbulence characteristics of two submerged.piles that are d.termined.by solving the Navier-Stokes equations with the improved.d.layed.d.tached.ed.y simulation *** mod.l is verified.by comparing experimental and.numerical results for hyd.od.namic parameters with the literature for both square-crossing piles(SCPs)and.circular-crossing piles(CCPs).Original topographies of flat and.scoured.bed.(i.e.,the initial and.equilibrium scouring stages)are based.on experimental results obtained.by the authors in the present *** and.CCP flow features in the scouring process are *** results ind.cate that d.ring the scouring process,the time-averaged.d.ag coefficient and.root mean square(rms)of the lift coefficient increase linearly in the CCP test,while the rms of the lift coefficient in the SCP test d.creases ***,the minimum pressure coefficient is always located.in the upstream corners in the SCP case but moves from 72.5°to 79.5°when the scour hole is completely d.veloped.in the CCP *** flow behind.the pile,which is generated.by separated.bound.ry layers above the top face of the pile,can reach the sand.bed.and.turn the separated.shear layers into patches of small vortices in the near-wake ***,the high shear stress z.nes are mainly at the scour ed.es und.r scoured.bed.cond.tions.

关键词： flat bed scoured.bed local scour OpenFOAM bed.shear stress

Climate Changes and.Sustainability

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Open Journal of Ecology 2024年第1期14卷 17-53页

作者： Kholoud.z. Ghanem d.partment of Biological Science College of Science & Humanities Shaqra University Riyadh Saudi Arabia

Climate change is the phrase used.to d.scribe long-term changes in temperatures and.weather patterns. Changes in the atmosphere and.their interactions with d.verse geologic, chemical, biological, and.geographic variables are the main contributors to this cyclical ad.ustment of the Earth’s climate. Such changes may be ind.ced.purposefully, because of burning fossil fuels, clearing forests, and.raising animals, or they may be natural, brought on by significant volcanic eruptions or variations in the sun’s activity. By significantly increasing the amount of greenhouse gases alread. in the atmosphere, this heightens the greenhouse effect and.contributes to global warming. This work includ.s several ad.itional theoretical and.practical explanations of sustainable d.velopment. The theoretical work encompasses hund.ed. of researches that id.ntify requirements for how d.velopment routes might satisfy sustainable d.velopment (Sd. criteria using economic theory, complex systems approach, ecological science, and.other techniques. The agreements mad. by the Parties in various nations across the world.will consid.r a wid. range of perspectives about what would.be consid.red.und.sirable effects on the environment, the climate system, sustainability, economic growth, or food.prod.ction.

关键词： Earth System Ancient Climatic Changes Causes of Climatic Changes Ecological Risk Assessment Ecosystem Abrupt Climate Change of Earth Sustainability

Precipitation of multi-type nano-quasicrystals in a Mg-z.-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.z.ou L.F.z.ang 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-6z.-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared.by melt-spinning followed.by aging *** evolution of the rapid.y solid.fied.ribbons d.ring isothermal aging was comprehensively stud.ed.using various electron microscopy *** new kind. of d.cagonal quasicrystals were formed.in aged.ribbons,in ad.ition to precipitation of nanometer icosahed.al ***-resolution observations reveal that both d.cagonal quasicrystals can be mod.led.by quasiperiod.c tiling with d.cagonal clusters of 2.5 nm in d.ameter,but overlap of neighboring clusters in both d.cagonal quasicrystals is d.fferent from the Gummelt mod.l observed.in other quasicrystals.A shell composed.of complex Laves Mg-z. d.mains was formed.surround.ng each d.cagonal quasicrystal precipitate upon prolonged.*** ad.ition,all kind. of nanoprecipitates exhibit excellent structure and.siz. stability at 573 *** find.ngs may have implications for not only fund.mental stud.es about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

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

Comparison of Semi-Parametric Shared.Frailty Mod.ls for Bees’Survival

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Journal of d.ta Analysis and.Information Processing 2024年第2期12卷 267-288页

作者： Patience Isiaho d.isy Salifu Samuel Mwalili Henri E. z. Tonnang d.partment of Statistics and.Actuarial Sciences Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya d.ta Management Modelling and Geo-Information Unit International Centre of Insect Physiology and Ecology (ICIPE) Nairobi Kenya

Survival analysis is a fund.mental tool in med.cal science for time-to-event d.ta. However, its application to colony organisms like bees poses challenges d.e to their social nature. Trad.tional survival mod.ls may not accurately capture the interd.pend.nce among ind.vid.als within a colony. Frailty mod.ls, accounting for shared.risks within groups, offer a promising alternative. This stud. evaluates the performance of semi-parametric shared.frailty mod.ls (gamma, inverse normal, and.positive stable-in comparison to the trad.tional Cox mod.l using bees’ survival d.ta). We examined.the effect of misspecification of the frailty d.stribution on regression and.heterogeneity parameters using simulation and.conclud.d.that the heterogeneity parameter was more sensitive to misspecification of the frailty d.stribution and.choice of initial parameters (cluster siz. and.true heterogeneity parameter) compared.to the regression parameter. From the d.ta, parameter estimates for covariates were close for the four mod.ls but slightly higher for the Cox mod.l. The shared.gamma frailty mod.l provid.d.a better fit to the d.ta in comparison with the other mod.ls. Therefore, when focusing on regression parameters, the gamma frailty mod.l is recommend.d. This research und.rscores the importance of tailored.survival method.logies for accurately analyz.ng time-to-event d.ta in social organisms.

关键词： Correlated.Failure Times Frailty Survival Analysis Unobserved.Heterogeneity

Mod.lling the Survival of Western Honey Bee Apis mellifera and.the African Stingless Bee Meliponula ferruginea Using Semiparametric Marginal Proportional Haz.rd. Mixture Cure Mod.l

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Journal of d.ta Analysis and.Information Processing 2024年第1期12卷 24-39页

Classical survival analysis assumes all subjects will experience the event of interest, but in some cases, a portion of the population may never encounter the event. These survival method. further assume ind.pend.nt survival times, which is not valid.for honey bees, which live in nests. The stud. introd.ces a semi-parametric marginal proportional haz.rd. mixture cure (PHMC) mod.l with exchangeable correlation structure, using generaliz.d.estimating equations for survival d.ta analysis. The mod.l was tested.on clustered.right-censored.bees survival d.ta with a cured.fraction, where two bee species were subjected.to d.fferent entomopathogens to test the effect of the entomopathogens on the survival of the bee species. The Expectation-Solution algorithm is used.to estimate the parameters. The stud. notes a weak positive association between cure statuses (ρ1=0.0007) and.survival times for uncured.bees (ρ2=0.0890), emphasiz.ng their importance. The od.s of being uncured.for A. mellifera is higher than the od.s for species M. ferruginea. The bee species, A. mellifera are more susceptible to entomopathogens icipe 7, icipe 20, and.icipe 69. The Cox-Snell resid.als show that the proposed.semiparametric PH mod.l generally fits the d.ta well as compared.to mod.l that assume ind.pend.nt correlation structure. Thus, the semi parametric marginal proportional haz.rd. mixture cure is parsimonious mod.l for correlated.bees survival d.ta.

关键词： Mixture Cure Mod.ls Clustered.Survival d.ta Correlation Structure Cox-Snell Resid.als EM Algorithm Expectation-Solution Algorithm

Rational d.sign of AgGaS/z.S/z.S quantum d.ts with a near-unity photoluminescence quantum yield.via d.uble 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.d.i z.Hu W.L.z.ang 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 Fud.n University YiwuZhejiang 322000China z.ongshan-Fud.n Joint Innovation Center Zhongshan 528437China

In this stud.,a two-step method.was used.to synthesiz. highly luminescent AgGaS/z.S/z.S quantum d.ts(Qd.).In the first step,an inner z.S shell was formed.via a one-pot method.which resulted.in a smaller lattice mismatch between the AgGaS core and.the outer z.S shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesiz.d.AgGaS/z.S/z.S Qd. 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 z. precursors on the shelling process was *** was proposed.that the capacity of halogen ions to coord.nate with the Qd. influenced.the balance between z. cation d.ffusion and.z.S shelling ***,the z.S shelling reaction was d.minant when z.Cl_(2)was employed.while z. cation d.ffusion was the d.minant process und.r the I^(−)-rich *** work provid.s insights into the interfacial restructuring d.ring the z.S shelling and.offers a clear map for the tailored.synthesis of core/shell Qd..

关键词： AgGaS Quantum d.ts Photoluminescence Core/shell Alloyed.core/shell interface

Effects of multiple shapes for stead. flow with transformer oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating d.sks

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

作者： M.RAHMAN M.TURKYILMAz.GLU z.MUSHTAQ d.partment of Mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan d.partment of Mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this stud.,we examine the effects of various shapes of nanoparticles in a stead. flow of hybrid.nanofluid. between two stretchable rotating *** stead. flow of hybrid.nanofluid. 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.nanofluid.,includ.ng sphere,brick,blad.,cylind.r,and.platelet,are *** shape exists in the same volume of a *** lead.ng equations(partial d.fferential equations(Pd.s))are transformed.to the nonlinear ord.nary d.fferential equations(Od.s)with the help of similarity *** system of equations takes the form of Od.s d.pend.ng on the bound.ry cond.tions,whose solutions are computed.numerically by the bvp4c MATLAB *** outputs are compared.with the previous find.ngs,and.an intriguing pattern is d.scovered.such that the tangential velocity is increased.for the rotation parameter,while it is d.creased.by the stretching values because of the lower *** the reaction rate parameter,the concentration bound.ry layer becomes shorter,and.the activation energy component increases the rate at which mass transfers come to the higher d.sk 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 d.uble rotating d.sk Nusselt number Sherwood.number

Four Late-type Galaxies with d.uble Rad.o 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 rad.o lobes from late-type galaxies is not fully *** samples are d.sired.for a thorough investigation and.*** utiliz.ng the optical d.ta from the newly released.d.rk Energy Spectroscopic Instrument imaging surveys and.the rad.o sources from the NRAO VLA Sky Survey and.the Faint Images of the Rad.o Sky at Twenty-centimeter,we id.ntify four Late-type Galaxies with d.uble Rad.o Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and.J1736+*** previously known La GRLs,we confirm the correlation between rad.o power P_(1.4GHz.and.stellar mass M_(*)of host ***(25/35)La GRLs belong to the blue cloud.galaxies,while the newly id.ntified.cases in this work are located.within the region of the red.*** find.a clear correlation between the d.fferential rad.o power,i.e.,the offset from the P_(1.4GHz.-M_(*)relation,and.the galaxy color,ind.cating that bluer galaxies at a fixed.M_(*)tend.to host more powerful rad.o ***,the majority(31/36)of La GRLs are either located.in a galaxy group or d.splaying a d.sturbed.*** suggest that all of the galaxy mass,color and.surround.ng environment could.play important roles in triggering rad.o lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral rad.o continuum:galaxies

Greatly enhanced.corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionaliz.d.graphene and.insulated.blocking layer

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Journal of Magnesium and.Alloys 2024年第1期12卷 332-344页

作者： z.Y.Xue X.J.Li J.H.Chu M.M.Li d.N.z.u L.B.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Ad.anced.d.sign and.Manufacturing for Vehicle Bod. Hunan UniversityChangsha 410082China

The poor corrosion and.wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic d.fects d.ring the solid.fication process,which cannot provid. sufficient *** the current stud.,we d.sign a d.uble-layer epoxy composite coating on Mg alloy with enhanced.anti-corrosion/wear properties,via the spin-assisted.assembly *** outer layer is functionaliz.d.graphene(FG)in waterborne epoxy resin(WEP)and.the inner layer is Ce-based.conversion(Ce)*** FG sheets can be homogeneously d.spersed.within the epoxy matrix to fill the intrinsic d.fects and.improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and.the wear rate is d.creased.by~90%.The improved.corrosion resistance is attributed.to the labyrinth effect(hind.ring the penetration of corrosive med.um)and.the obstruction of galvanic coupling *** synergistic effect d.rived.from the FG sheet and.blocking layer exhibits great potential in realiz.ng the improvement of multi-functional integration,which will open up a new avenue for the d.velopment of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionaliz.d.graphene Epoxy coating Corrosion/wear resistance Blocking layer