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A novel approach to the dynamic response analysis of Euler-Bernoulli beams resting on a Winkler soil model and subjected to impact loads

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 389-401页

作者： Adolfo Foriero Filippo Santucci de Magistris Giovanni Fabbrocino Département de génie civil et de génie des eaux Pavillon Adrien-PouliotUniversitéLavalQuébecCanada Dipartimento di Bioscienze e Territorio Universitàdegli Studi del MoliseCampobassoItaly construction Technologies Institute National Research CouncilITC-CNRL’AquilaItaly

This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact *** approach considers that damping has much less importance in controlling the maximum response to impulsive loadings because the maximum response is reached in a very short time,before the damping forces can dissipate a significant portion of the energy input into the *** development of two sine series solutions,relating to different types of impulsive loadings,one involving a single concentrated force and the other a distributed line load,are *** study revealed that when a simply supported Euler-Bernoulli beam,resting on a Winkler soil model,is subject to an impact load,the resulting vertical displacements,bending moments and shear forces produced along the span of the beam are considerably *** particular,the quantification of this effect is best observed,relative to the corresponding static solution,via an amplification *** computed impact amplification factors,for the sub-grade moduli used in this study,were in magnitude greater than 2,thus confirming the multiple-degree-of-freedom nature of the problem.

关键词： beam-Winkler-soil model sub-grade moduli impact load impact distributed line load dynamic solution impact amplification factor

Hole cleaning evaluation and installation spacing optimization of cuttings bed remover in extended-reach drilling

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Petroleum Science 2024年第3期21卷 2005-2022页

作者： Shuo Peng Wen-Jun Huang de-Li Gao MOE Key Laboratory of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing102249China

In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the *** cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,and pipe stuck probably occur,which results in a lot of non-productive time and remedial *** bed remover can efficiently destroy deposited cuttings in time through hydraulic and mechanical stirring *** paper aims to build a method for hole cleaning evaluation and installation spacing optimization of cuttings bed remover to improve the wellbore cleaning ***,a computational Fluid Dynamics approach with Eulerian—Eulerian multiphase model was utilized to investigate the mechanism of cuttings transportation,and a new type of cuttings bed remover was ***,an evaluation method of hole cleaning effect of remover was *** that,the effects of several drilling parameters on hole cleaning including flow rate of drilling fluid,rotational speed of drillpipe,rate of penetration,wellbore size,rheological property of drilling fluid,and remover eccentricity on the performance of cuttings bed remover were *** results demonstrate that the new type of remover with streamline blade performs better than conventional *** efficiency of hole cleaning is greatly improved by increasing the rotational speed of drillpipe,flow rate of drilling fluid,remover eccentricity,and 6 rpm Fann dial reading for drilling *** higher rate of penetration and large wellbore size result in worse hole *** findings can serve as an important guide for the structure optimization design of cuttings bed remover and installation spacing of removers.

关键词： Extended-reach drlling Drilling hydraulics cuttings transport Hole cleaning cuttings bed remover

Simulated rainfall in Brazil:An alternative for assesment of soil surface processes and an opportunity for technological development

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International Soil and Water conservation Research 2024年第1期12卷 29-42页

作者： camila calazans da Silva Luz Wilk Sampaio de Almeida Adilson Pacheco de Souza Nivaldo Schultz Jamil Alexandre Ayach Anache Daniel Fonseca de carvalho Postgraduate Program in Agronomy-Soil Sciences Federal Rural University of Rio de JaneiroSeropédicaRJBrazil Agronomy department Federal Institute of EducationScience and Technology of RondôniaAriquemesROBrazil Federal University of Mato Grosso SinopMTBrazil Federal Rural University of Rio de Janeiro SeropédicaRJBrazil Federal University of Mato Grosso do Sul Campo GrandeMSBrazil

Rainfall simulators(RS)have been used,above all,to evaluate hydrological processes related to soil water infiltration,surface runoff and soil *** allow repeatability of rain application with different precipitation intensities in field and/or laboratory conditions and should produce events with physical characteristics similar to natural *** this manuscript,we carried out a bibliometric and scientometric analysis of studies with simulated rainfall in Brazil to assess the temporal evolution of publications,the main topics addressed and the degree of technological development of the *** searched for the terms“rainfall simulator”OR“simulated rainfall”AND“Brazil”in the Scopus,Web of Science,SciELO and Google Scholar *** found 143 articles published in the last 37 years(1985-2022).Our findings indicate that the main research areas covered in papers are soil erosion(57.34%),soil water infiltration(24.47%),nutrient losses(9.8%)and RS development and calibration/assessment(8.39%).In recent years,the number of published papers in international high-impact factor journals has *** of the papers(49.65%)refer to studies carried out by institutions located in the south and southeast regions of ***,there is a large gap of studies on simulated rainfall in other regions of Brazil,where important biomes such as the cerrado,Amazon,caatinga,and their transitions are *** study informs research priorities on soil erosion under simulated rainfall and provides a bibliographic database that can assist in more detailed future analyses.

关键词： Rainfall simulator Soil and water losses Soil water infiltration Bibliometrics Scientific review

Traditional chinese medicine for the treatment of immune-related nephropathy:A review

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Acta Pharmaceutica Sinica B 2024年第1期14卷 38-66页

作者： Pu Jiang changliang Yao de-an Guo School of Pharmacy Nanjing University of Chinese MedicineNanjing 210023China Shanghai Research center for Modernization of Traditional chinese Medicine National Engineering Research Center of TCM Standardization TechnologyShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China

Immune-related nephropathy(IRN)refers to immune-response-mediated glomerulonephritis and is the main cause of end-stage renal *** pathogenesis of IRN is not fully understood;therefore,treatment is *** chinese medicines(TcMs)have potent clinical effects in the treatment of the IRN conditions immunoglobulin A nephropathy,lupus nephropathy,and diabetic *** underlying mechanisms mainly include its inhibition of inflammation;improvements to renal interstitial fibrosis,oxidative stress,autophagy,apoptosis;and regulation of *** this review,we summarize the clinical symptoms of the three IRN subtypes and the use of TcM prescriptions,herbs,and bioactive compounds in treating IRN,as well as the potential mechanisms,intending to provide a reference for the future study of TcM as IRN treatments.

关键词： IgA nephropathy Diabetic nephropathy Lupus nephritis Traditional chinese medicine Immunity Pathogenesis Mechanism Pathophysiology

ENSO impacts on litter stocks and water holding capacity in secondary forests in eastern Amazonia

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Journal of Forestry Research 2024年第1期35卷 83-89页

作者： Julia Isabella de Matos Rodrigues Walmer Bruno Rocha Martins Victor Pereira de Oliveira Myriam Suelen da Silva Wanzerley Hélio Brito dos Santos Júnior Francisco de Assis Oliveira Graduate Program in Forestry Sciences Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Tv.Pau-AmareloCapitão PoçoPará68650-000Brazil National Institute of Amazonia Research Av.Constelação Cruzeiro do SulManausAmazonas 69060-062Brazil

Among the impacts of climate change,there is the intensification of phenomena such as the El Niño South-ern Oscillation(ENSO)responsible for El Niño and La Niñ***,understanding their effects on the functional pro-cesses of forests is ***,this study evaluated the effects of ENSO on litter stock and water holding capac-ity(WHc)in a successional forest in eastern *** occurred in periods with the most rainfall in El Niño(2019)and least in La Niña(2021)*** permanent plots were used to sample *** effects were evident for WHc,higher during El Niñ***,this influence was not clear for litter,as only in the rainy season effects were *** was a positive correlation of WHc with precipitation and humidity,while litter stocks were negatively correlated with temperature and wind *** the subject of this study requires long-term assessments,preliminary results suggests that,depending on the intensity of ENSO,forest functional processes can be strongly impacted and *** conclusion reinforces warnings by the scientific community about the impacts of climate change on the maintenance of litter stocks,decomposition and,consequently,the biogeochemical cycle and essential ecosystem services for the maintenance of Amazonia *** need to develop long-term research to understand the effects of climatic change on litter stocks and water holding capacity is highlighted,especially in Amazonia.

关键词： Seasonality climate change Succession ecosystem Biogeochemical cycle Amazonia biodiversity

changes in calcium accumulation and utilization efficiency and their impact on recycling,immobilization,and export across the oil palm cycle

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Oil crop Science 2024年第3期9卷 143-150页

作者： Ismael de Jesus Matos Viégas Luma castro de Souza Eric Victor de Oliveira Ferreira Milton Garcia costa Glauco André dos Santos Nogueira Vitor Resende do Nascimento candido Ferreira de Oliveira Neto capanema campus Federal Rural University of the Amazon(UFRA)Av.Barao de CapanemaCaixa D'agua5514-6434ParaBrazil center of Agricultural and Environmental Sciences Federal University of Maranhao(UFMA)ChapadinhaBR-222km 04SNBoa Vista65500000MaranhaoBrazilc capitao Poço campus Federal Rural University of the Amazon(UFRA)Tv.Pau AmareloS/n-Vila Nova68650-000Capitao PoçoParaBrazil department of Soil Science Sao Paulo State University(Unesp)School of Agricultural and Veterinarian SciencesJaboticabalVia de Acesso Prof.Paulo Donato CastelaneCastellane-S/N-Vila Industrial14884-900Sao PauloBrazil Institute of Agricultural Sciences(IcA) Federal Rural University of the Amazon(UFRA)Estr.Principal da Ufra2150Curio-Utinga66077-580BelemParaBrazil

Effective calcium(ca)management is crucial for optimizing oil palm cultivation and enhancing crop *** study aimed to gain insights into the dynamics of ca concentration,accumulation,exportation,immobilization,and recycling in various oil palm organs relative to plant *** experiment was conducted at the Agropalma enterprise site in the northeastern region of Para State,Brazil,evaluating seven plant age treatments:2,3,4,5,6,7,and 8 years *** a completely randomized design with four *** results demonstrated an age-related increase in ca concentration in petioles,rachis,arrows,male inflorescences,peduncles,and ***,ca accumulation exhibited an upward trend in all organs with progressing plant ***,the study revealed an enhanced ca use efficiency across all plant organs in correlation with the age of oil palm *** findings underscore the dynamic nutritional demands of oil palm,influencing ca immobilization,cycling,and export throughout its developmental stages.

关键词： Elaeis guineensis Jacq ca cycling ca export ca immobilization ca use efficiency Plant nutrition Amazon

The effect of abiotic stresses on plant c:N:P homeostasis and their mitigation by silicon

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The crop Journal 2024年第2期12卷 340-353页

作者： Milton Garcia costa Renato de Mello Prado Luiz Fabiano Palaretti Jonas Pereira de Souza Júnior department of Agricultural Production Science School of Agricultural and Veterinarian SciencesSão Paulo State UniversityJaboticabalBrazil

In crop plants, various environmental stresses affect the balance of carbon, nitrogen, and phosphorus(c:N:P), leading to biochemical and physiological alterations and reductions in yield. Silicon(Si) is a beneficial element that alleviates plant stress. Most studies involving silicon have focused on physiological responses, such as improvements in photosynthetic processes, water use efficiency, and antioxidant defense systems. But recent research suggests that stressed plants facing either limited or excessive resources(water, light, nutrients, and toxic elements), strategically employ Si to maintain c:N:P homeostasis, thereby minimizing biomass losses. Understanding the role of Si in mitigating the impact of abiotic stresses on plants by regulating c:N:P homeostasis holds great potential for advancing sustainable agricultural practices in crop production. This review presents recent advances in characterizing the influence of environmental stresses on c:N:P homeostasis, as well as the role of Si in preserving c:N:P equilibrium and attenuating biological damage associated with abiotic stress. It underscores the beneficial effects of Si in sustaining c:N:P homeostasis and increasing yield via improved nutritional efficiency and stress mitigation.

关键词： Nutritional stoichiometry Elemental stoichiometry Beneficial element Environmental stresses Nutritional efficiency carbon use efficiency Agricultural sustainability

co-Optimization of Behind-the-Meter and Front-of-Meter Value Streams in community Batteries

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Journal of Modern Power Systems and clean Energy 2024年第2期12卷 334-345页

作者： carmen Bas Domenech Antonella Maria de corato Pierluigi Mancarella University of Melbourne Parkville 2010VictoriaAustralia department of Electrical and Electronic Engineering The University of ManchesterManchesterU.K. IEEE

community batteries(cBs)are emerging to support and even enable energy communities and generally help consumers,especially space-constrained ones,to access potential techno-economic benefits from storage and support local grid ***,the economic viability of cB projects is often *** this regard,typical feasibility studies assess cB value for behind-the-meter(BTM)operation or whole-sale market participation,i.e.,front-of-meter(FOM).This work proposes a novel techno-economic operational framework that allows systematic assessment of the different options and introduces a two-meter architecture that co-optimizes both BTM and FOM benefits.A real cB project application in Australia is used to demonstrate the significant two-meter co-optimization opportunities that could enhance the business case of cB and energy communities by multi-service provision and value stacking.

关键词： Behind-the-meter community battery distributed energy resource(deR) energy community front-of-meter value stacking

Photoionisation detection of a single Er3+ ion with sub-100-ns time resolution

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National Science Review 2024年第4期11卷 38-45页

作者： Yangbo Zhang Wenda Fan Jiliang Yang Hao Guan Qi Zhang Xi Qin changkui Duan Gabriele G.de Boo Brett c.Johnson Jeffrey c.Mc callum Matthew J.Sellars Sven Rogge chunming Yin Jiangfeng Du cAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences University of Science and Technology of China cAS center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China centre of Excellence for Quantum computation and communication Technology School of Physics University of New South Wales centre of Excellence for Quantum computation and communication Technology School of Engineering RMIT University centre of Excellence for Quantum computation and communication Technology School of Physics University of Melbourne centre of Excellence for Quantum computation and communication Technology Research School of Physics and Engineering Australian National University

Efficient detection of single optical centres in solids is essential for quantum information processing, sensing and single-photon generation *** this work,we use radio-frequency（RF） reflectometry to electrically detect the photoionisation induced by a single Er3+ion in *** high bandwidth and sensitivity of the RF reflectometry provide sub-100-ns time resolution for the photoionisation *** this technique,the optically excited state lifetime of a single Er3+ion in a Si nano-transistor is measured for the first time to be 0.49±0.04μ*** results demonstrate an efficient approach for detecting a charge state change induced by Er excitation and *** approach could be used for fast readout of other single optical centres in solids and is attractive for large-scale integrated optical quantum systems thanks to the multi-channel RF reflectometry demonstrated with frequency multiplexing techniques.

关键词： single optical centres erbium ions RF reflectometry photoionisation detection