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Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

Journal of Iron and Steel Research International 2024年第3期31卷 752-766页

作者： Yan Qi Xin Zhang Jun Li Dong-liang Zhao Shi-hai Guo Yang-huan Zhang Department of Functional material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of integrated Exploitation of Bayan Obo Multi-Metal resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

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Improving hydrogen storage thermodynamics and kinetics of Ce-Mg-Ni-based alloy by mechanical milling with TiF_(3)

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Journal of Magnesium and Alloys 2024年第4期12卷 1593-1607页

作者： Hongwei Shang Wei Zhang Xin Wei Yaqin Li Zeming Yuan Jun Li Yanghuan Zhang School of Mechanical and Electrical Engineering Chuzhou UniversityChuzhou 239000China Department of Functional material Research Central Iron and Steel Research InstituteNo.76 Xueyuannan RoadHaidian DistrictBeijing 100081China Key Laboratory of integrated Exploitation of Bayan-Obo Multi-Metal resources Inner Mongolia University of Science and TechnologyBaotou 014010China China Rare Earth New material(Weishan)Co. Ltd.Jining 277600China

Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not *** efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocomposite materials of Mg and *** this experiment,TiF_(3)was selected as an additive,and the mechanical milling method was employed to prepare the experimental *** alloys used in this experiment were the as-cast Ce_(5)Mg_(85)Ni_(10),as-milled Ce_(5)Mg_(85)Ni_(10)and Ce_(5)Mg_(85)Ni_(10)+3 wt.%*** phase transformation,structural evolution,isothermal and non-isothermal hydrogenation and dehydrogenation performances of the alloys were inspected by XRD,SEM,TEM,Sievert apparatus,DSC and *** revealed that nanocrystalline appeared in the as-milled *** with the as-cast alloy,ball milling made the particle dimension and grain size decrease dramatically and the defect density increase *** addition of TiF_(3)made the surface of ball milling alloy particles markedly coarser and more *** milling and adding TiF_(3)distinctly improved the activation and kinetics of the ***,ball milling along with TiF_(3)can decrease the onset dehydrogenation temperature of Mg-based hydrides and slightly ameliorate their thermodynamics.

关键词： Mg-based hydrides TiF_(3) Ball milling Thermodynamics Kinetics

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Fundamentals and progress of the manifold method based on independent covers

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Science China(Technological Sciences) 2024年第4期67卷 966-991页

作者： SU HaiDong LIN ShaoZhong XIE ZhiQiang GONG YaQi QI YongFeng material and Engineering Structure Department Yangtze River Scientific Research InstituteWuhan 430010China Research Center of Water Engineering Safety and Disaster Prevention of Ministry of Water resources Wuhan 430010China

Aiming to solve mesh generation,computational stability,accuracy control,and other problems encountered with existing numerical methods,such as the finite element method and the finite volume method,a new numerical computational method for continuum mechanics,namely the manifold method based on independent covers(MMIC),is proposed based on the concept of mathematical manifolds,to form partitioned series solutions of partial differential *** partitions,the cover meshes have the characteristics of arbitrary shape,arbitrary connection,and arbitrary *** are expected to fundamentally solve the mesh generation problem and can also simulate the precise geometric boundaries of the CAD model and strictly impose boundary *** the selection of series solutions,local analytical solutions(such as series solutions at crack tips and series solutions in infinite domains)or proper forms of complete series can be used to reflect the local or global characteristics of the physical field to accelerate *** applications are presented.A new method of beam,plate,and shell analysis is *** deformation characteristics of beams,plates,and shells are simulated with polynomial series of suitable forms,and the analysis of curved beams and shells with accurate geometric representation is *** the static elastic analysis of two-dimensional structures,a mesh splitting algorithm is proposed,and h-p version adaptive analysis is carried out with error ***,automatic computation integrated with CAD is *** analysis is also attempted for the solution of differential equations of *** the one-dimensional convection-diffusion equation and Burgers equation,calculation results with high precision are obtained in strong convection and shock wave simulations,avoiding nonphysical *** solving the two-dimensional incompressible Navier-Stokes equation is also *** series solution formula is used to o

关键词： series solutions mesh generation adaptive analysis fixed meshes numerical manifold method

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Boundless love:a German Professor Uli Schwarz in China

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Protein & Cell 2024年第8期15卷 553-558页

作者： Le Kang State Key Laboratory of integrated management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China

More than 20 years ago,an old German man embarked on a quest to explore the suburbs of Shanghai and the villages of jiangsu Province in search of antique Chinese *** was not a mere antique collector or aficionado of ancient furmiture,but a German scientist motivated by his profound love of Chinese *** name was Uli Schwarz(Fig.1),a distinguished German scientist who had dedicated the majority of his life to promoting cross-cultural scientific exchanges,an effort that left an indelible mark on the landscape of research collaborations between China and Germany.

关键词： Schwarz German landscape

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Establishment of genome-editing system and assembly of a near-complete genome in broomcorn millet

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Journal of Integrative Plant Biology 2024年第8期66卷 1688-1702页

作者： Yang Liu Zixiang Cheng Weiyao Chen Chuanyin Wu Jinfeng Chen Yi Sui State Key Laboratory of integrated management of Pest Insects and Rodents Institute of Zoologythe Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Crop Gene resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China

The ancient crop broomcorn millet(Panicum miliaceum L.)is an indispensable orphan crop in semi-arid regions due to its short life cycle and excellent abiotic stress *** advantages make it an important alternative crop to increase food security and achieve the goal of zero hunger,particularly in light of the uncertainty of global climate ***,functional genomic and biotechnological research in broomcorn millet has been hampered due to a lack of genetic tools such as transformation and genome-editing ***,we successfully performed genome editing of broomcorn *** identified an elite variety,Hongmi,that produces embryogenic callus and has high shoot regeneration ability in in vitro *** established an Agrobacterium tumefaciens-mediated genetic transformation protocol and a clustered regularly interspaced short palindromic repeats(CRISPR)/Cas9-mediated genome-editing system for *** these techniques,we produced herbicide-resistant transgenic plants and edited phytoene desaturase(Pm PDS),which is involved in chlorophyll *** facilitate the rapid adoption of Hongmi as a model line for broomcorn millet research,we assembled a near-complete genome sequence of Hongmi and comprehensively annotated its ***,our results open the door to improving broomcorn millet using biotechnology.

关键词： broomcorn millet CRISPR/Cas9 editing genome assembly herbicide resistance transformation system

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Deformation and stability of the seawall,considering the strength uncertainty of cement mixing piles

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 483-501页

作者： Yuansheng YU Lingling LI Xiangmiao KONG Chengyuan LI Zhen GUO Key Laboratory of Offshore Geotechnics and material of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Hainan institute Zhejiang UniversitySanya572000China Ninghai Highway and Transportation management Center Ningbo315600China Ninghai Traffic Engineering Construction management institute Ningbo315600China

The cement mixing (CM) pile is a common method of improving soft offshore ground. The strength growth of CM piles under complex conditions is affected by many factors, especially the cement and moisture contents, and shows significant uncertainty. To investigate the stochasticity of the early strength of CM piles and its impact on the displacement and stability of a seawall, a series of laboratory tests and numerical analyses were carried out in this study. Vane shear tests were conducted on the cement-solidified soil to determine the relationships between the undrained shear strength s_(u) of the cement soil curing in the seawater and the cement content a_(c), as well as the in situ soil moisture content w. It can be inferred that the 24 h undrained shear strength follows a normal distribution. A numerical model considering the random CM pile strength was established to investigate the deformation of the seawall. Due to the uncertainty of CM pile strength, the displacement of the seawall demonstrates a certain discreteness. The decrease of the mean undrained shear strength of CM piles causes a corresponding increase in the average displacement of the seawall. When the mean strength of CM piles is lower than a certain threshold, there is a risk of instability. Furthermore, the heterogeneity of the strength within an individual CM pile also has an impact on seawall displacement. Attention should be paid to the uncertainty of CM pile strength to control displacement and stability.

关键词： Construction uncertainty Cement mixing(CM)pile Strength of cement soil Seawall stability Random finite element method(RFEM) Monte Carlo simulation(MCS)

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Enhancing 3D Reconstruction Accuracy of FIB Tomography Data Using Multi‑voltage Images and Multimodal Machine Learning

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Nanomanufacturing and Metrology 2024年第1期7卷 48-60页

作者： Trushal Sardhara Alexander Shkurmanov Yong Li Lukas Riedel Shan Shi Christian J.Cyron Roland C.Aydin Martin Ritter institute for Continuum and material Mechanics Hamburg University of TechnologyHamburgGermany Electron Microscopy Unit Hamburg University of TechnologyHamburgGermany institute of materials Physics and Technology Hamburg University of TechnologyHamburgGermany institute of materials Mechanics Helmholtz-Zentrum HereonGeesthachtGermany Research Group of integrated Metallic Nanomaterials Systems Hamburg University of TechnologyHamburgGermany institute of material Systems Modeling Helmholtz-Zentrum HereonGeesthachtGermany

FIB-SEM tomography is a powerful technique that integrates a focused ion beam(FIB)and a scanning electron microscope(SEM)to capture high-resolution imaging data of *** approach involves collecting in-plane SEM imagesand using FIB to remove material layers for imaging subsequent planes,thereby producing image ***,theseimage stacks in FIB-SEM tomography are subject to the shine-through effect,which makes structures visible from theposterior regions of the current *** artifact introduces an ambiguity between image intensity and structures in thecurrent plane,making conventional segmentation methods such as thresholding or the k-means algorithm *** study,we propose a multimodal machine learning approach that combines intensity information obtained at differentelectron beam accelerating voltages to improve the three-dimensional(3D)reconstruction of *** treatingthe increased shine-through effect at higher accelerating voltages as a form of additional information,the proposed methodsignificantly improves segmentation accuracy and leads to more precise 3D reconstructions for real FIB tomography data.

关键词： Multimodal machine learning Multi-voltage images FIB-SEM Overdeterministic systems 3D reconstruction FIB tomography

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Dieback of managed spruce stands in western Germany promotes beetle diversity

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Journal of Forestry Research 2024年第3期35卷 55-71页

作者： Eva Plath Chantal Trauth Jan Gerhards Laura Griebel Klaus Fischer Department Biology Institute of Integrated Natural SciencesKoblenz-Landau University56070 KoblenzGermany

Biodiversity loss is a significant problem at a global scale and may be amplified by climate *** recent years,coniferous forests have had substantial die-back across Europe due to drought and subsequent bark-beetle *** many studies on the consequences of disturbance and subsequent management have focused on natural stands,management implications for managed spruce stands are not well understood,even though such stands are widespread throughout *** this study,beetle taxonomy,conservation value,and community com-position are compared among spruce plantations and four post-disturbance management approaches:standing dead-wood,lying deadwood,clear cuts,and long-term *** and community composition differed significantly among management categories,while different beetle fami-lies responded *** spruce stands harbored the lowest beetle diversity while the highest taxonomic diver-sity and conservation value was on clear cuts and stands with lying or standing *** proportion of forest specialists was highest in successional *** summary,different forest management categories harbored distinct beetle communities at the family-,species-,and ecological guild ***,post-disturbance management should consider the landscape scale and include different management *** enhances landscape heterogeneity and thus overall biodiversity but could also mitigate negative impacts of natural disturbances on ecosystem services.

关键词： Bark-beetle outbreak Forest dieback Spruce Deadwood Nature conservation Beetle biodiversity-Coleoptera Coniferous forests

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Effects of zero-valent iron added in the flooding or drainage process on cadmium immobilization in an acid paddy soil

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Journal of Environmental Sciences 2024年第4期138卷 19-31页

作者： Hanbing Meng Shiwen Hu Zebin Hong Wenting Chi Guojun Chen Kuan Cheng QiWang Tongxu Liu Fangbai Li Kexue Liu Yang Yang Guangzhou institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China School of resources and Planning Guangzhou Xinhua UniversityGuangzhou 510310China University of Chinese Academy of Sciences Beijing 100049China

Zero-valent iron(ZVI)is a promising material for the remediation of Cd-contaminated paddy ***,the effects of ZVI added during flooding or drainage processes on cadmium(Cd)retention remain ***,Cd-contaminated paddy soil was incubated for 40days of flooding and then for 15 days of drainage,and the underlying mechanisms of Cd immobilization coupled with Fe/S/N redox processes were *** addition of ZVI to the flooding process was more conducive to Cd *** potential available Cd was detected by adding ZVI before flooding,which may be due to the increase in paddy soil pH and newly formed secondary Fe ***,the reductive dissolution of Fe minerals promoted the release of soil colloids,thereby increasing significantly the surface sites and causing Cd ***,the addition of ZVI before flooding played a vital role in Cd retention after soil *** contrast,the addition of ZVI in the drainage phase was not conducive to Cd retention,which might be due to the rapid decrease in soil pH that inhibited Cd adsorption and further immobilization on soil *** findings of this study demonstrated that Cd availability in paddy soil was largely reduced by adding ZVI during the flooding period and provide a novel insight into the mechanisms of ZVI remediation in Cd-contaminated paddy soils.

关键词： Paddy soil Zero-valent iron Cadmium Flooding and drainage Remediation

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Cold storage alters the fat-trehalose trade-off,decreases the flight ability,and maintains the high survival rate and flight speed of Osmia excavata(Hymenoptera:Megachilidae)

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Insect Science 2024年第3期31卷 927-936页

作者： Yingying Song Li Liu Fang Ouyang Hongying Cui Wenxiu Guo Suhong Lv Baohua Ye Lili Li Yi Yu Xingyuan Men institute of Plant Protection Shandong Academy of Agricultural SciencesJinanChina College of Plant Protection Shandong Agricultural UniversityJinanChina State Key Laboratory of integrated management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBejingChina

Osmia solitary bees are important pollinators of various crops *** has been widely used to synchronize the emergence time of Osmia species from cocoons with the blooming time of different crops,but the fitness of Osmia after refrigeration remains ***,the effects of long-term refrigeration at 0℃on the vitality,flight ability,and metabolism of Osmia excavata,which is known as the"king of pollination"in China,were *** survival rate(>90%before 120 d),weight loss rate(<15%after 170 d),and mean flight speed of *** were not greatly affected after long-term *** content of fats,which have antifreeze and energy storage properties,was not significantly altered in *** before 130 d of refrigeration,which might explain why the survival rates and flight speed of *** remained high after long-term ***,the flight duration and distance decreased significantly(P<0.05),and both were positively correlated with the reduced trehalose levels in ***(r=[+0.69]-[+0.71];P<0.05).Overall,these findings indicate that the pollination potential of *** for various crops with different flowering periods is high after long-term refrigeration;however,long-term refrigeration may decrease pollination *** findings highlight new research directions that could improve the ecological service function of refrigerated ***.

关键词： ecological service value flight ability Osmia pollination efficiency refrigeration vitality

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