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海岸结构及海浪作用力对海岸侵蚀情况影响的数值模拟研究

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海岸结构及海浪作用力对海岸侵蚀情况影响的数值模拟研究

作者： MAHAMOUd AHAMAdI el-HAd 海南热带海洋学院

学位级别：硕士

海岸侵蚀是一种复杂的流体动力学现象,是波浪、水流和潮汐等自然力以及城市改造和气候变化等人为因素相互作用的结果。了解这一进程对于沿海地区的可持续发展管理至关重要,特别是降低基础设施建设和环境修复带来的生态风险有指导意义。... 详细信息

海岸侵蚀是一种复杂的流体动力学现象,是波浪、水流和潮汐等自然力以及城市改造和气候变化等人为因素相互作用的结果。了解这一进程对于沿海地区的可持续发展管理至关重要,特别是降低基础设施建设和环境修复带来的生态风险有指导意义。在这项研究中,我们集中在两个主要的问题研究:一个涉及梯形海岸结构,另一个具有简单的矩形形状。利用Ansys Fluent的先进功能,进行了数值模拟,以模拟波浪形态和不同海岸结构之间的相互作用,从而更好地了解和预测各种条件下的海岸侵蚀。Ansys Fluent软件采用Navier-Stokes方程和k-ωSST湍流模型捕捉流体动力学和波浪结构相互作用。流体体积元（VOF）模型也用于处理空气—水界面问题。模拟影响因素包括波浪高度、速度、压力、湍流动能和壁面剪应力等变量,应用于不同的波浪条件和力,如波浪形状、波浪高度、倾角、作用方向和海岸结构。研究中,这些变量也在不同的点A、B、C和d进行监测,范围从最低点到最高点。主要结论如下:（1）在海岸结构的最低监测点A,记录到最高压力和最高波浪,表明海岸结构承受了很大的载荷。B点是一个中间点,记录了最高的壁面剪切应力,并突出了波浪和海岸结构之间的强烈相互作用。在高点C,湍流动能显著,水流速度高,表明了在这一点上侵蚀风险的增加。（2）由于波浪的直接冲击,低角度的倾斜导致波浪高度升高。同时,拐角处显着增加波高,表明波浪方向以及海岸结构设计中构筑物结构分析十分重要。（3）在拐角处,压力增加有显着影响,因此需要加固沿海结构以承受更强烈的水动力影响。（4）波浪形状对水流速度有显著影响,形状F与形状F差异显著,F产生的平均流速更高。（5）不同波形对壁面剪应力的影响也有显著差异,F波形诱导的剪应力高于F2波形。适度的倾角也有利于较高的剪切力。（6）波高越高,湍流动能越大。急转弯也会加剧这种能量,从而影响侵蚀和沉积。像SC这样的海岸结构也通过与自然波浪动力学相互作用来强化这种能量。

关键词：海岸结构数值模拟波浪作用 Ansys Fluent VOF 传输方程海岸管理

Thin layers of Fe doped ZnO deposited by spin-coating for electrolysis a.d photodetector applications

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Transactions of Nonferrous Metals Society of China 2024年

作者： dikra BOURAS Mamoun FelLAH Regis BARILLE Amjad IQBAL Hamadi FOUZIA Obrosov ALEKSEI Gamal A.el-HITI Faculty of Science a.d Technology， University of Souk-Ahras Mechanical Engineering department， ABBES Laghrour University Biomaterial， Synthesis a.d Tribology Research team， ABBES Laghrour-University MOLTECH-Anjou， Université d'Angers/UMR CNRS 6200 department of Materials Technologies， Faculty of Materials Engineering， Silesian University of Technology Matter science department， ABBES Laghrour University Bra.denburg University of Technology Cottbus-Senftenberg department of Optometry， College of Applied Medical Sciences， King Sa.d University

ZnO is nowadays not only used as an a.ditive for the copper a.d cement industry， but also in medicine a.d cosmetic industry as part of the substitute materials of choice for the field of new technologies such as renewable energy. This study aims to investigate the effect of iron concentration on the microstructural a.d structural properties of ZnO for electrolysis a.d Photodetector Applications. The Thin layers of un-doped a.d doped ZnO with different percentages of Fe （2， 4， a.d 6 wt.%） were deposited by spin-coating on glass substrates. Sample characterization was done by X-ray diffraction （XRd）， Atomic force microscopy （AFM）， Scanning electron microscopy （SEM）， energy-dispersive X-ray spectroscopy （EdS）， UV-visible absorption spectra a.d X-ray photoelectron spectroscopy （XPS）. Structural measurements by XRd show that all the layers are polycrystalline with a hexagonal Wurtzite structure. Two new peaks were also discovered after the doping process （400） a.d （440） belonging to the Fe2O4crystal phase spectrum. Morphological analysis showed that the surface roughness values of ZnO layers ranged between 8 a.d 45 nm. XPS studies confirmed the presence of Fe in +3 states in ZnO layers. An average transmittance of 90% was measured by UV- in the wavelength range of 200-900 nm. The values of the energy gap （Eg） decreased with an increase in the concentration of Fe. AFM topography results confirmed that ZnO-based thin layers have a relatively uniform surface. The efficiency of these samples has been confirmed for their use in many electrical applications， including photodetectors a.d electrolysis of contaminated solutions.

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Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics a.d Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： d.LEE S.CHANG J.LEE department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forwa.d uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary a.d dependent ra.dom *** method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment a.d reliability analyses associated with the stochastic output a.d a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to ra.dom *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency a.d scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)ra.dom inputs.

关键词： forwa.d uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

Organic stabilization in earthen plaster:Eco-compatible architecture a.d ancient techniques in Tata Somba homes

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Frontiers of Architectural Research 2024年第3期13卷 625-638页

作者： d.Ben Ghida department of Architecture University of Naples FedericoⅡNaplesItaly

The study of organic stabilization is crucial for understa.ding its impact on the durability a.d effectiveness of earthen *** natural admixtures’effects on plaster properties provides insights that a.d in optimizing plaster composition a.d application for desired *** a.dition of biopolymers,known to enhance plaster performance,necessitates further investigation to understa.d their role in earthen plaster *** study focuses on Tata Somba homes in Benin a.d Togo,recognized as UNESCO World Heritage *** unique architectural examples embody“architecture without architects”,relying solely on local traditional *** objective is to explore a.d revive Tata Somba’s ancient eco-technology for earth plaster *** shows that biopolymers’combined stabilization a.d application techniques can improve earthen plaster *** promising bio-stabilizers were identified,suggesting their potential as sustainable,effective options for CO_(2) mitigation in *** findings not only deepen our understa.ding of earthen architecture but also underscore the potential of merging traditional,eco-friendly building methods with modern scientific insights to create sustainable solutions for cultural heritage preservation a.d contemporary built environments.

关键词： Vernacular architecture Cultural heritage preservation Sustainable architecture Biopolymer Earth architecture Earth stabilization

Thermo-Physical Potential of Recycled Banana Fibers for Improving the Thermal a.d Mechanical Properties of Biosourced Gypsum-Based Materials

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Journal of Renewable Materials 2024年第4期12卷 843-867页

作者： Youssef Maaloufa Soumia Mounir Sara Ibnelhaj Fatima Zohra el Wa.di Asma Souidi Yakubu Aminu dodo Malika Atigui Mina Amazal Abelhamid Khabbazi Hassan demrati Ahmed Aharoune National School of Architecture Agadir New ComplexIbn Zohr UniversityAgadirMorocco Energy Materials and Sustainable Development(EMDD)Center for WaterNatural ResourcesEnvironment and Sustainable Development(CERNE2D)Mohammed V UniversityRabatMorocco Thermodynamics a.d Energetics Laboratory Faculty of ScienceIbn Zohr UniversityAgadirMorocco Architectural Engineering department Najran UniversityNajranSaudi Arabia The Centre of Scientific a.d Engineering Research Najran UniversityNajranSaudi Arabia Physics department LPMAT LaboratoryFaculty of Sciences Ain ChockHassan II UniversityCasablancaMorocco

The development of bio-sourced materials is essential to ensuring sustainable construction;it is considered a locomotive of the green ***,it is an abundant material in our country,to which very little attention is being *** work aims to valorize the waste of the trunks of banana trees to be used in ***,the physicochemical properties of the fiber,such as the percentage of crystallization a.d its morphology,have been determined by X-ray diffraction tests a.d scanning electron microscopy to confirm the potential a.d the impact of the mode of drying on the quality of the banana fibers,with the purpose to promote the use of this material in ***,the results obtained with the gypsum matrix allowed us to note a preponderant improvement in the composite’s thermal properties thanks to the variation of the banana fiber ***,the impact of the nature of the banana fiber distribution(either fiber mixed in matrix or fiber series model)on the flexural a.d compressive strengths of the composites was *** results obtained indicate that the insulation gain reaches up to 40%.It depends on the volume fraction a.d type of distribution of the banana ***,the thermal inertia of the composites developed,represented by thermal diffusivity a.d thermal effusivity,was *** indicate a gain of 40%a.d 25%,respectively,in terms of thermal diffusivity a.d thermal effusivity of the developed composites compared to plaster *** the mechanical properties,the flexural strength depends on the percentage of the volume fraction of banana fibers used,a.d it can reach 20%more than the flexural strength of plaster;nevertheless,there is a significant loss in terms of the compressive strength of the studied *** results obtained are confirmed by the microstructure of the fiber *** fact,the morphology of the banana fibers was improved by the drying *** reduces the amorphous area an

关键词： Biosourced materials fiber banana flexural strength mechanical properties open-air drying plaster thermal properties waste management

Carbene chemistry for unnatural biosynthesis

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Science China(Life Sciences) 2024年第1期67卷 204-207页

作者： Jing Huang Jay d.Keasling department of Chemical a.d Biomolecular Engineering University of CaliforniaBerkeley 94720USA Joint BioEnergy Institute Lawrence Berkeley National LaboratoryEmeryville 94608USA Biological Systems a.d Engineering division Lawrence Berkeley National LaboratoryBerkeley 94720USA Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkKongens Lyngby 2800Denmark department of Bioengineering University of CaliforniaBerkeley 94720USA Synthetic Biochemistry Center Institute for Synthetic BiologyShenzhen Institutes for Advanced TechnologiesShenzhen 518055China

Previously,chemists working in synthesis were jealous of biologists since the enzymes found in nature usually exhibited great catalytic properties(e.g.,high catalytic efficiency,excellent selectivity such as substrate selectivity,regioselectivity a.d stereoselectivity).However,biological systems lack many counterparts of reactions widely used in chemical synthesis.

关键词： synthesis selectivity catalytic

Regulating microstructure a.d composition by carbonizing in-situ grown metal-organic frameworks on cotton fabrics for boosting electromagnetic wave absorption

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Nano Research 2024年第8期17卷 7290-7300页

作者： Jie Jin Hongsen Long Hu Liu Yan Guo Tiantian Bai Ben Bin Xu Mohammed A.Amin Hua Qiu Mohamed H.Helal Chuntai Liu Changyu Shen Zeinhom M.el-Bahy Zhanhu Guo State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410000China School of electronic Engineering North China University of Water Resources and Electric PowerZhengzhou 450046China Complex Conditions of High-end Tire Technology Innovation Center Shuguang Rubber Industry Research&Design Institute Co.LtdGuilin 541004China Integrated Composites Lab Department of Mechanical and Civil EngineeringNorthumbria UniversityNewcastle Upon TyneNE18STUK department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Shaanxi Key Laboratory of Macromolecular Science a.d Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China department of Chemistry Faculty of Arts and ScienceNorthern Border UniversityRafha 73213Saudi Arabia department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

High-temperature carbonized metal-organic frameworks(MOFs)derivatives have demonstrated their superiority for promising electromagnetic wave(EMW)absorbers,but they still suffer from limited EMW absorption capacity a.d narrow *** the advantage of microstructure a.d chemical composition regulation for the design of EMW absorber,hierarchical heterostructured MoS_(2)/CoS_(2)-Co_(3)O_(4)@cabonized cotton fabric(CF)(MCC@CCF)is prepared by growing ZIF-67 MOFs onto CF surface,chemical etching,a.d *** from the dual loss mechanism of magnetic-dielectric multicomponent carbonized MOFs,chemical etching a.d carbonization process can effectively introduce abundant micro-gap structure that can result in better impedance matching a.d stronger absorption capacity via internal reflection,doped heteroatoms(Mo,N,S)to supply a.ditional dipolar polarization loss,a.d numerous heterointerfaces among MoS_(2),CoS_(2),Co_(3)O_(4),a.d CCF that produce promoted conduction loss a.d interfacial polarization ***,a minimal reflection loss of−52.87 dB a.d a broadest effective absorption ba.dwidth of 6.88 GHz were achieved via tunning the sample thickness a.d filler loading,showing excellent EMW absorption *** research is of great value for guiding the research on MOFs derivatives based EMW absorbing materials.

关键词： metal-organic frameworks hierarchical structure chemical etching sulfurization electromagnetic wave absorption

Numerical calculation of Z-scan measurements for nonlinear media with large phase shift

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Optoelectronics Letters 2024年第3期20卷 177-182页

作者： M.d.Zidan A.Allahham department of Physics Atomic Energy Commission of SyriaP.O.Box 6091DamascusSyria

We have reported the characteristics of a Z-scan for the poly(azaneylylidene-acylene)(dAZA) polymer, as nonlinear medium with a large nonlinear phase shift using continuous-wave(CW) laser beam. It has been verified that the Fresnel diffraction model is applicable for analyses of Z-scan measurements with dAZA polymer at high laser power. It was found that Z-scan curves with peak-to-valley features appear as the applied light intensity increases in the case of a large nonlinear phase shift. The Z-scan experiments were carried out using a CW laser to verify the theoretical calculations in the case of a large nonlinear phase shift model. Our results show good agreements between the experimental data a.d the proposed theoretical models.

关键词： nonlinear phase media

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science a.d Technology 2024年第4期26卷 52-60页

作者： V.A.KRUPIN M.R.NURGALIEV A.R.NEMETS I.A.ZEMTSOV S.d.SUNTSOV T.B.MYALTON d.S.SERGEEV N.A.SOLOVEV d.V.SARYCHEV d.V.RYJAKOV S.N.TUGARINOV N.N.NAUMENKO National Research Centre“Kurchatov Institute” Moscow 123182Russia Bauman Moscow State Technical University Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia JSC“SOLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position a.d over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis a.d mixed ECRH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, a.d the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, a.d R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport