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Alternate erosion and deposition in the Yangtze Estuary and the future change

Journal of geographical Sciences 2020年第1期30卷 145-163页

作者： ZHU Boyuan LI Yitian YUE Yao YANg Yunping LIANg Enhang ZHANg Chuncai BORTHWICK Alistair g.L. School of Hydraulic Engineering Changsha University of Science&TechnologyChangsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China School of Water Resources and Hydropower Engineering State Key Laboratory of Water Resources and Hydropower Engineering ScienceWuhan UniversityWuhan 430072China Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringMinistry of TransportTianjin 300456China The Key Laboratory of Water and Sediment Sciences Ministry of EducationCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China School of Engineering The University of EdinburghThe King’s BuildingsEdinburgh EH93JLUK

The morphological changing trend of the Yangtze Estuary, the largest estuary of Asia, has become a focus of research in recent years. Based on a long series of topographic data from 1950 to 2015, this paper studied the erosion-deposition pattern of the entire Yangtze Estuary. An alternation between erosion and deposition was found during the past 65 years, which was in correspondence to the alternation between flood and dry periods identified by multi-year average duration days of high-level water flow (defined as discharge ≥ 60,000 m3/s, namely, D≥60,000) from the Yangtze River Basin. A quantitative relationship was further developed between the erosional/depositional rate of the Yangtze Estuary and the interpreting variables of yearly water discharge, D≥60,000 and yearly river sediment load, with contributing rates of 1%, 59% and 40%, respectively. Mechanism behind the alternate erosion and deposition pattern was analyzed by examining residual water surface slope and the corresponding capacity of sediment transport in flood and dry periods. In flood periods, a larger discharge results in steeper slope of residual water level which permits a greater capacity of sediment transport. Therefore, more bed materials can be washed to the sea, leading to erosion of the estuary. In contrast, flatter slope of residual water level occurs in dry periods, and deposition dominates the estuarine area due to the decreased capacity of sediment transport and the increased backwater effect of flood-tide. Coastal dynamics and estuarine engineering projects alter the local morphological changes, but slightly affect the total erosional/depositional rate of the whole estuarine region. Heavy sedimentation within the Yangtze Estuary after the impoundment of the Three gorges Dam can be attributed to the reduced occurrence frequency of flood years due to water regulation by the dam, and largely (at least 36%-52%) sourced from the sea. Deposition is still poss

关键词： Yangtze Estuary erosion and deposition alternation total sediment load evolutional trend

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Low-temperature alteration of uranium–thorium bearing minerals and its significance in neoformation of radioactive minerals in stream sediments of Wadi El-Reddah, North Eastern Desert, Egypt

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Acta geochimica 2020年第1期39卷 96-115页

作者： O.A.Ebyan H.A.Khamis A.R.Baghdady M.g.El-Feky N.S.Abed geology Department Faculty of ScienceAin Shams UniversityCairo 11566Egypt Nuclear Materials Authority(NMA) P.O.Box 530El-MaadiCairoEgypt

The stream sediments of Wadi El Reddah(North Eastern Desert,Egypt)are geochemically and mineralogically *** content of radioactive and other heavy minerals is mainly represented by thorite,uranothorite,zircon,monazite,xenotime,columbite,fergusonite,and unknown rare earth elements(REEs)bearing minerals as well as *** emphasis on REE content of thorite,uranothorite,zircon and xenotime has been done to correlate them with the increase of uranium contents in these *** key evidence for the presence lowtemperature alteration processes includes the presence of some zircon crystals as remnants after complete dissolution of the overgrowth zircon in severe acidic environment,the sulphur content,biogenic minerals,occurrence of unusual minerals as cassiterite pore filling in zircon,variation in the REEs content from the surrounding granites to the stream sediments and the abundance of monazite in the surrounding *** minerals are partially and/or completely altered,which indicated by the pseudomorphism of zircon by xenotime,thorite,and uranothorite.

关键词： Zircon Thorite Xenotime Radioactive minerals Low-temperature alteration Wadi El-Reddah

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Effect of high shear homogenization on quality characteristics of bael fruit pulp

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Food Quality and Safety 2022年第1期6卷 81-92页

作者： Meenatai g.Kamble Anurag Singh Pramod Kumar Prabhakar Murlidhar Meghwal Sukh Veer Singh Ajay V.Chinchkar Department of Food Science and Technology National Institute of Food Technology Entrepreneurship and Management(NIFTEM)SonipatHaryana-131028India

Response surface methodology was used to investigate the influence of high shear homogenization speed(A:3000-12000 r/min)and processing time(B:30-120 min)on bael fruit pulp quality *** experimental results were best fitted in the suggested quadratic model to delineate and envision the responses in terms of color(values of L^(*),meaning brightness to blackness,1oo-0;a^(*),meaning green-a^(*)to red+a^(*);and b^(*),meaning blue-b^(*)to yellow+b),total soluble solids,ascorbic acid,viscosity,andβ-carotene content with the highest coefficients of determination(R2)ranging from 0.80 to ***(Pge in the L^(*)value,total soluble solids,ascorbic acid,andβ-carotene content was found with change in homogenization *** interaction effect of homogenization showed a significant difference in a^(*)value and total soluble solid content of the *** best homogenization conditions were determined via multiple response optimization as 10682 r/min speed and 43.18 min process *** quality parameters of the pulp at optimized conditions were observed as L^(*)15.35,a^(*)4.51,b^(*)10.25,ascorbic acid 18.64 mg/100 g,viscosity 5349 cP,andβ-carotene 4.14μg/100 *** addition,total phenolic content,flavonoid content,and antioxidant content of homogenized bael fruit pulp was found to significantly(Pg gallic acid equivalent(gAE)/100 mL,(147.39±0.69)to(156.10±1.11)mg quercetin equivalent(QE)/100 mL,and(41.77%±0.60%)to(66.53%±0.41%),***,this strategy could be used in fruit processing industries to process highly fibrous fruits and nonuniform-textured fruit pulptoavoid sedimentation whileretaining functionality.

关键词： Aegle marmelos L. underutilized fruit viscosity bioactive compounds color values

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B-site substituted solid solutions on the base of sodium-bismuth titanate

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Journal of Advanced Dielectrics 2016年第4期6卷 12-21页

作者： V.M.Ishchuk L.g.gusakova N.g.Kisel D.V.Kuzenko N.A.Spiridonov V.L.Sobolev Science&Technology Center`Reactivelectron'of the Ukrainian National Academy of Sciences Donetsk 83049Ukraine Physics Department South Dakota School of Mines&Technology Rapid CitySD 57701USA

The paper presents results of studies of the formation of phases during the solid-state synthesis in the[(Na_(0.5)Bi_(0.5)T_(0.80)Ba_(0.20)]Ti_(1-y)B_(y)TO_(3)system of solid solutions with B-site *** substitutions by zirconium,tin and ion complexes(In_(0.5)Nb_(0.5)T and(Fe_(0.5)Nb_(0.5)T have been *** has been found that the synthesis is a multi-step process associated with the formation of a number of intermediate phases(depending on the compositions and calcination temperatures).Single-phase solid solutions have been produced at the calcination temperatures in the interval 1000–1100℃.An increase in the substituting ions concentration leads to a linear increase of the crystal cell *** the same time,the tolerance factor gets reduced boosting the stability of the antiferroelectric phase as compared to that of the ferroelectric phase.

关键词： (Na_(0:5)Bi_(0:5))TTiO_(3) solid solution ions substitution solid-state synthesis phase transition.

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Partial Derivatives, Singular Integrals and Sobolev Spaces in Dyadic Settings

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Analysis in Theory and Applications 2023年第3期39卷 287-298页

作者： Hugo Aimar Juan Comesatti Ivana gómez Luis Nowak Instituto de Matemática Aplicada del Litoral“Dra.Eleonor Harboure” UNLCONICETCCT CONICET Santa FePredio“Dr.Alberto Cassano”Colectora Ruta Nac.168 km 0Paraje El PozoS3007ABA Santa FeArgentina Instituto de Investigación en Tecnologías y Ciencias de la Ingeniería Universidad Nacional del ComahueCONICET/Departamento de Matemática-FaEA-UNComaNeuquénArgentina

In this note we show that the general theory of vector valued singular integral operators of Calderón-Zygmund defined on general metric measure spaces,can be applied to obtain Sobolev type regularity properties for solutions of the dyadic fractional *** doing so,we define partial derivatives in terms of Haar multipliers and dyadic homogeneous singular integral operators.

关键词： Sobolev regularity Haar basis space of homogeneous type Calder´on-Zygmund operator dyadic analysis

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Analysis of the Supply Chain in Industrial Companies in guayaquil,Ecuador-A Secondary Publication

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Proceedings of Business and Economic Studies 2024年第1期7卷 242-255页

作者： génesis Belén Linzán Soledispa Betty Janeth Soledispa Canarte Víctor Alfonso ChávezSoledispa Oscar Rolando Fiallos gonzález Universidad Politécnica Salesiana GuayaquilEcuador Universidad Estatal del Sur de Manabí ManabíEcuador Universidad Católica de Santiago de guayaquil GuayaquilEcuador

This research clearly outlines the supply chain in a process of evolution and digital transformation,where the collaboration of its members is concentrated,having technological tools to help chain *** analyze the advantages that this transformation produces in the supply chain,as well as its different processes,this study has a systemic perspective that involves precise elements for organizational development,such as the different phases of each process,operations,logistics,and *** must be borne in mind that any strategy in industrial companies grants the automation of procedures in the supply chain and determines a product in any phase of production,making the organization more sensitive to any variation in *** methodology included a bibliographic and non-experimental review that allows a descriptive and analytical study,which details the various characteristics of the fact that is being investigated,collecting information through interviews with different people who are involved with industrial *** the results obtained,it was identified that digital transformation helps reduce costs and generates greater *** conclusion,it was obtained that the digital supply chain helps in each of the phases of the processes,these are supervised by devices that help to have fast and effective information.

关键词： Digital transformation Supply chain Industries 4.0 Sustainability

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Exploring ferromagnetic half-metallic nature of Cs2NpBr6 via spin polarized density functional theory

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Chinese Physics B 2020年第6期29卷 364-368页

作者： Malak Azmat Ali g Murtaza A Laref Department of Physics Government Post Graduate Jahanzeb College Saidu SharifSwat 19130Khyber PakhtunkhwaPakistan Materials Modeling Laboratory Department of PhysicsIslamia College Peshawar 25120Khyber PakhtunkhwaPakistan Department of Physics and Astronomy College of SciencesKing Saud UniversityRiyadh11451 Kingdom of Saudi Arabia

By employing the spin resolved density functional theory, half-metallic character is investigated in Cs2NpBr6 having a K2PtCl6-type structure. The results precisely predict the half-metallic behavior of Cs2NpBr6. In spin-down state it presents an indirect band gap, while in spin-up channel it turns metallic. The structure optimization confirms the half-metallic nature in ferromagnetic configuration. The calculated magnetic moment is 3 μB toward which the main contributor is the Np ***, all the computed results are compared with the available experimental and theoretical values. According to the present analysis, we recommend Cs2NpBr6 for spintronic applications.

关键词： half-metallic ferromagnetic magnetic moment spintronics

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Quadrilateral Cell-Based Anisotropic Adaptive Solution for the Euler Equations

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Communications in Computational Physics 2011年第1期9卷 68-88页

作者： H.W.Zheng N.Qin F.C.g.A.Nicolleau C.Shu Department of Mechanical Engineering University of SheffieldMappin StreetSheffield S13JDUK Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260.

An anisotropic solution adaptive method based on unstructured quadrilateral meshes for inviscid compressible flows is *** data structure,the directional refinement and coarsening,including the method for initializing the refined new cells,for the anisotropic adaptive method are *** provides efficient high resolution of flow features,which are aligned with the original quadrilateral mesh *** different cases are provided to show that it could be used to resolve the anisotropic flow features and be applied to model the complex geometry as well as to keep a relative high order of accuracy on an efficient anisotropic mesh.

关键词： Anisotropic adaptive mesh refinement quadrilateral mesh finite volume face-based algorithm HLLC Euler equation

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Implementation of a Petrographical and Petrophysical Workflow Protocol for Studying the Impact of Heterogeneity on the Rock Typing and Reservoir Quality of Reefal Limestone:A Case Study on the Nullipore Carbonates in the gulf of Suez

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Acta geologica Sinica(English Edition) 2021年第5期95卷 1746-1762页

作者： Mona g.SAFA Bassem S.NABAWY Ahmed M.K.BASAL Mohammad A.OMRAN Aref LASHIN geology Department Faculty of ScienceDamietta UniversityNew Damietta CityEgypt Department of geophysical Sciences National Research CentreDokkiCairoEgypt Petroleum and Natural gas Engineering Department College of EngineeringKing Saud UniversityRiyadh 11421Saudi Arabia Benha University Faculty of ScienceGeology DepartmentBenhaEgypt

This study focuses on the heterogeneity of the middle Miocene syn-rift Belayim nullipore(reefal)marine sequences in the gulf of Suez and its impacts on reservoir *** sequences consist of coralline algal reef limestones with a highly complex dual-porosity system of primary and secondary porosities of widely varying *** achieve a precise mathematical modeling of these reservoir sequences,a workflow protocol was applied to separate these sequences into a number of hydraulic flow units(HFUs)and reservoir rock types(RRTs).This has been achieved by conducting a conventional core analysis on the nullipore marine *** illustrate the heterogeneity of the nullipore reservoir,the Dykstra-Parsons coefficient(V)has been estimated(V=0.91),indicating an extremely heterogeneous reservoir.A slight to high anisotropy(λ_(k))has been assigned for the studied nullipore sequences.A stratigraphic modified Lorenz plot(SMLP)was applied to define the optimum number of HFUs and barriers/baffles in each of the studied *** the permeability-porosity,reservoir quality index-normalized porosity index(RQI-NPI)and the RQI-flow zone indicator(RQIFZI)plots,the discrete rock types(DRT)and the R35 techniques enable the discrimination of the reservoir sequences into 4 RRTs/*** RRT4 packstone samples are characterized by the best reservoir properties(moderate permeability anisotropy,with a good-to-fair reservoir quality index),whereas the RRT1 mudstone samples have the lowest flow and storage capacities,as well as the tightest reservoir quality.

关键词： reservoir heterogeneity nullipore rock typing hydraulic flow units Dykstra-Parsons coefficient stratigraphic modified Lorenz plot(SMLP)

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The cis-trans Isomerisation of Homologous 2-Hydroxycycloalkanecarboxylic Acids under Basic Conditions

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Chinese Journal of Chemistry 2006年第12期24卷 1792-1795页

作者： gYARMATI Cs. Zsuzsanna PALINKO lstván BOKROS Attila MARTINEK A. Tamás BERNATH gábor Institute of Pharmaceutical Chemistry University ofSzeged Szeged POB 121 H-6701 Hungary Research group for Heterocyclic Chemistry of the Hungarian Academy of Sciences and University of Szeged Szeged POB 121 H-6701 Hungary Department of Organic Chemistry University of Szeged Szeged Ddm tér 8 H.6720 Hungary

The cis→trans isomerisation of homologous 2-hydroxycycloalkanecarboxylic acids in strongly basic aqueous solution was studied starting from the cis isomers. It was found that the cyclopentane, cyclohexane and cycloheptane homologues afforded synthetically useful amounts of the trans acids and the procedure resulted in relatively small quantities of the corresponding olefinic acids. In contrast, the isomerisation of the cis-2-hydroxycyclooctanecarboxylic acid produced roughly equal amounts of the cis and trans isomers and the 1-cyclooctenecarboxylic acid at equilibrium. Molecular modelling with the PM3 semiempirical method of the reactants, products and the intermediates applying explicit water molecules as reaction medium gave a fair estimate for the rate sequence of the idealised （dehydration-free） isomerisation reactions in aqueous base solution.

关键词： geometric isomerisation base catalysis reaction mechanism molecular modelling

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