检索结果-南通市图书馆

Impact of wetting-drying cycles and acidic conditions on the soil aggregate stability of yellow‒brown soil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Mountain Science 2024年第6期21卷 2075-2090页

作者： XIA Zhenyao ni Yuanzhen LIU Deyu WANG Di XIAO Hai Key Laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of EducationYichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002China

Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external *** study was conducted to explore the effect of external environment(wetting-drying cycles and acidic conditions)on the soil aggregate distribution and stability and identify the key soil physicochemical factors that affect the soil aggregate *** yellow‒brown soil from the Three Gorges Reservoir area(TGRA)was used,and 8 wetting-drying conditions(0,1,2,3,4,5,10 and 15 cycles)were simulated under 4 acidic conditions(pH=3,4,5 and 7).The particle size distribution and soil aggregate stability were determined by wet sieving method,the contribution of environmental factors(acid condition,wetting-drying cycle and their combined action)to the soil aggregate stability was clarified and the key soil physicochemical factors that affect the soil aggregate stability under wetting-drying cycles and acidic conditions were determined by using the Pearson’s correlation analysis,Partial least squares path modeling(PLS‒PM)and multiple linear regression *** results indicate that wetting-drying cycles and acidic conditions have significant effects on the stability of soil aggregates,the soil aggregate stability gradually decreases with increasing number of wetting-drying cycles and it obviously decreases with the increase of ***,the combination of wetting-drying cycles and acidic conditions aggravate the reduction in the soil aggregate *** wetting-drying cycles,acidic conditions and their combined effect imposes significant impact on the soil aggregate stability,and the wetting-drying cycles exert the greatest *** soil aggregate stability is significantly correlated with the pH,Ca^(2+),Mg^(2+),maximum disintegration index(MDI)and soil bulk density(SBD).The PLS‒PM and multiple linear regression analysis further reveal that the soil aggre

关键词： Yellow‒brown soil Wetting-drying cycles Acidic conditions Soil aggregate stability Soil disintegration

niCoZn/C@melamine sponge-derived carbon composites with highperformance electromagnetic wave absorption

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2274-2286页

作者： Xiubo Xie Heshan Wang Hideo Kimura Cui ni Wei Du Guanglei Wu School of Environmental and Material Engineering Yantai UniversityYantai 264005China Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of AeronauticsBinzhou 256603China Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China

niMZn/C@melamine sponge-derived carbon(MSDC)composites(M=Co,Fe,and Mn)were prepared by a vacuum pump-ing solution method followed by carbonization.A large number of carbon nanotubes(CNTs)homogeneously attached to the surfaces of the three-dimensional cross-linked of the sponge-derived carbon in the niCoZn/C@MSDC composite,and CNTs were detected in the niFeZn/C@MSDC and niMnZn/C@MSDC ***_(3)ZnC_(0.7),ni_(3)Fe,and MnO in-situ formed in the niFeZn/C@MSDC and niMnZn/C@MSDC *** CNTs in the niCoZn/C@MSDC composite efficiently modulated its complex ***,the composite exhibited the best performance among the composites,with the minimum reflection loss(RL_(min))of-33.1 dB at 18 GHz and thickness of 1.4 *** bandwidth for RL of≤-10 dB was up to 5.04 GHz at the thickness of 1.7 mm and loading of 25wt%.The op-timized impedance matching,enhanced interfacial and dipole polarization,remarkable conduction loss,and multiple reflections and scat-tering of the incident microwaves improved the microwave absorption *** effects of Co,ni,and Fe on the phase and mor-phology provided an alternative way for developing highly efficient and broadband microwave absorbers.

关键词： microwave absorption carbon nanotube element substitution melamine sponge-derived carbon

Utilization of recycled solid waste as ecological reclamation materials based on plant growth experiments and soil quality analysis

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2024年第3期21卷 820-834页

作者： QIN Xiaochun ni Anchen YANG Dongxiao XING Wenhu LIU Shiliang College of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Shanxi Road&Bridge Construction Group Co. LtdShanxi 030006China School of Environment Beijing Normal UniversityBeijing 111875China

During the highway construction,a large number of spoil areas will be generated while a large amount of waste slag and soil could not be rationally ***,the vegetation recovery is slow in the spoil areas due to the soil *** at recycling the solid waste,the sieved engineering waste slag with local red clay and corn straw biochar was supplied to solve the problem of insufficient nutrients in engineering waste slag and *** addition,planting experiments of alfalfa(Medicago sativa L.)and Amorpha fruticosa *** with physical and chemical experiments were carried out to prove the feasibility of the novel improved substrate for the reclamation of spoil *** results show that the substrate's improvement effect is mainly affected by the soil to slag ratio and the biochar *** improvement effect of soil matrix in highway spoil area decreases with the increase of the waste slag content,especially when the soil-slag ratio is less than 3,and the promotion of plants is *** the contrary,the improvement effect is proportional to the biochar content(3%-8%).But it is noted that the Cu and Pb in the soil will exceed the clean limit corresponding to the Nemero soil pollution index level when the biochar content is 8%.Therefore,it is recommended that the soil-slag ratio should be≥3,and the biochar content should reach 3%-5%.This research provides experimental basis and technical support for utilizing solid waste resources in the reclamation of highway spoil areas.

关键词： Highway Spoil area Waste slag Modified soil Ecological reclamation

Unusual Single Electron Transfer Reactions between Alkenes and Iodine Electrophiles

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第5期42卷 471-477页

作者： Zhengzhao Lou jingyu Hu Chuanfa ni Xiu Wang jinbo Hu Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Ling Ling RoadShanghai200032 China School of Physical Science and Technology ShanghaiTech University100 Haike RoadShanghai201210 China

The electrophilic addition to an alkene with an electrophile has been widely studied and applied in organic *** organic chemistry textbook describes the classical reaction between an alkene and an iodine electrophile(such as elemental iodine and N-iodosuccinimide(niS))as a typical ionic reaction,in which an iodonium ion is formed and then attacked by a ***,in this article,we report a new and unusual reaction mode between an alkene and niS;that is,a single electron transfer(SET)process occurs between these two reactants by forming an electron-donor acceptor *** only does this unusual single electron transfer reaction between an alkene and niS add fundamentally important knowledge to organic chemistry,it also provides a valuable synthetic method as the new SET reaction mode with opposite regioselectivity as compared with the traditional ionic mode.

关键词： Electrophilic addition Radical ions Reaction mechanisms Alkenes Fluorine

Theoretical Modeling and Surface Roughness Prediction of Microtextured Surfaces in Ultrasonic Vibration-Assisted Milling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2024年第2期37卷 163-183页

作者： Chenbing ni Junjie Zhu Youqiang Wang Dejian Liu Xuezhao Wang Lida Zhu School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266525China School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China

Textured surfaces with certain micro/nano structures have been proven to possess some advanced functions,such as reducing friction,improving wear and increasing *** prediction of micro/nano surface textures is of great significance for the design,fabrication and application of functional textured *** this paper,based on the kinematic analysis of cutter teeth,the discretization of ultrasonic machining process,transformation method of coordinate systems and the cubic spline data interpolation,an integrated theoretical model was established to characterize the distribution and geometric features of micro textures on the surfaces machined by different types of ultrasonic vibration-assisted milling(UVAM).Based on the theoretical model,the effect of key process parameters(vibration directions,vibration dimensions,cutting parameters and vibration parameters)on tool trajectories and microtextured surface morphology in UVAM is ***,the effect of phase difference on the elliptical shape in 2D/3D ultrasonic elliptical vibration-assisted milling(UEVAM)was *** to conventional numerical models,the method of the cubic spline data interpolation is applied to the simulation of microtextured surface morphology in UVAM,which is more suitable for characterizing the morphological features of microtextured surfaces than traditional methods due to the presence of numerous micro *** prediction of surface roughness indicates that the magnitude of ultrasonic amplitude in z-direction should be strictly limited in 1D rotary UVAM,2D and 3D UEVAM due to the unfavorable effect of axial ultrasonic vibration on the surface *** study can provide theoretical guidance for the design and fabrication of microtextured surfaces in UVAM.

关键词： Theoretical modeling Microtextured surface Ultrasonic vibration-assisted milling Cubic spline interpolation Surface roughness

Reconstruct recent multi-population migration history by using identical-by-descent sharing

在线全文

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2024年第6期51卷 642-651页

作者： Wenxiao Zhang Kai Yuan Ru Wen Haifang Li Xumin ni School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044China The Stanley Center for Psychiatric Research Broad Institute of MIT and HarvardCambridgeMA 02142USA Baidu Incorporated Beijing 100085China

Identical-by-descent(IBD)is a fundamental genomic characteristic in population genetics and has been widely used for population history ***,limited by the nature of IBD,which could only capture the relationship between two individuals/haplotypes,existing IBD-based history inference is constrained to two *** this study,we propose a framework by leveraging IBD sharing in multipopulation and develop a method,MatrixiBD,to reconstruct recent multi-population migration ***,we employ the structured coalescent theory to precisely model the genealogical process and then estimate the IBD sharing across multiple *** our model,we establish a theoretical connection between migration history and IBD *** method is rigorously evaluated through simulations,revealing its remarkable accuracy and ***,we apply MatrixiBD to Central and South Asia in the Human Genome Diversity Project and successfully reconstruct the recent migration history of three closely related populations in South *** taking into account the IBD sharing across multiple populations simultaneously,MatrixlBD enables us to attain clearer and more comprehensive insights into the history of regions characterized by complex migration dynamics,providing a holistic perspective on intricate patterns embedded within the recent population migration history.

关键词： Population genetics IBD sharing Migration history Structured coalescent theory Gene flow

A modified back analysis method for deep excavation with multi-objective optimization procedure

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1373-1387页

作者： Chenyang Zhao Le Chen Pengpeng ni Wenjun Xia Bin Wang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Guangdong Research Center for Underground Space Exploitation Technology School of Civil EngineeringSun Yat-sen UniversityGuangzhou510275China Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) Zhuhai519000China Jiangsu Provincial Transportation Engineering Construction Bureau Nanjing210004China

Real-time prediction of excavation-induced displacement of retaining pile during the deep excavation process is crucial for construction *** paper proposes a modified back analysis method with multi-objective optimization procedure,which enables a real-time prediction of horizontal displacement of retaining pile during *** opposed to the traditional stage-by-stage back analysis,time series monitoring data till the current excavation stage are utilized to form a multi-objective ***,the multi-objective particle swarm optimization (MOPSO) algorithm is applied for parameter *** optimized model parameters are immediately adopted to predict the excavation-induced pile deformation in the continuous construction *** achieve efficient parameter optimization and real-time prediction of system behavior,the back propagation neural network (BPNN) is established to substitute the finite element model,which is further implemented together with MOPSO for automatic *** proposed approach is applied in the Taihu tunnel excavation project,where the effectiveness of the method is demonstrated via the comparisons with the site monitoring *** method is reliable with a prediction accuracy of more than 90%.Moreover,different optimization algorithms,including non-dominated sorting genetic algorithm (NSGA-II),Pareto Envelope-based Selection Algorithm II (PESA-II) and MOPSO,are compared,and their influences on the prediction accuracy at different excavation stages are *** results show that MOPSO has the best performance for high dimensional optimization task.

关键词： Multi-objective optimization Back analysis Surrogate model Multi-objective particle swarm optimization(MOPSO) Deep excavation

Multi-Fidelity Simulation of Gas Turbine Overall Performance by Directly Coupling High-Fidelity Models of Multiple Rotating Components

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第4期33卷 1357-1378页

作者： DENG Weimin XU Yibing ni Ming WEI Zuojun GAN Xiaohua REN Guangming Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen518055China School of Aerospace Engineering Tsinghua UniversityBeijing100084China Shenzhen Key Laboratory of Wide-Speed-Range and Variable-Density Continuous Wind Tunnel Shenzhen Science and Technology Innovation CommitteeShenzhen518000China

Multi-fidelity simulations incorporate computational fluid dynamics(CFD) models into a thermodynamic model,enabling the simulation of the overall performance of an entire gas turbine with high-fidelity *** iterative coupled methods rely on characteristic maps,while fully coupled methods directly incorporate high-fidelity ***,fully coupled methods face challenges in simulating rotating components,including weak convergence and complex *** address these challenges,a fully coupled method with logarithmic transformations was developed to directly integrate high-fidelity CFD models of multiple rotating *** developed fully coupled method was then applied to evaluate the overall performance of a KJ66 micro gas turbine across various off-design *** developed fully coupled method was also compared with the traditional iterative coupled ***,experimental data from ground tests were conducted to verify its *** convergence history indicated that the proposed fully coupled method exhibited stable convergence,even under far-off-design *** experimental verification demonstrated that the multi-fidelity simulation with the fully coupled method achieved high accuracy in off-design *** analysis revealed inherent differences in the coupling methods of CFD models between the developed fully coupled and traditional iterative coupled *** inherent differences provide valuable insights for reducing errors between the component-level model and CFD models in different coupling *** developed fully coupled method,introducing logarithmic transformations,offers more realistic support for the detailed and optimal design of high-fidelity rotating components within the overall performance platform of gas turbines.

关键词： multi-fidelity fully coupled method iterative coupled method gas turbine component-level model

The CBL-interacting protein kinase OsCIPK1 phosphorylated by SAPK10 positively regulates responses to ABA and osmotic stress in rice

在线全文

学校读者我要写书评

暂无评论

The Crop Journal 2024年第2期12卷 364-374页

作者： Caihua Qin Xing Fan Qianqian Fang Lan ni Mingyi Jiang College of Life Sciences State Key Laboratory of Crop Genetics&Germplasm Enhancement and UtilizationKey Laboratory of Crop Physiology Ecology and Production ManagementMinistry of AgricultureNanjing Agricultural UniversityNanjing 210095JiangsuChina

SubclassⅢsucrose nonfermenting1-related protein kinase 2s(SnRK2s)function in ABA and abiotic stress responses by unknown *** found that osmotic stress/ABA-activated protein kinase 10(SAPK10),a member of rice SnRK2s,physically interacted with CBL-interacting protein kinase 1(OsCIPK1).OsCIPK1 expression was up-regulated by ABA and PEG treatment,and overexpression increased the ABA sensitivity of seed germination and root growth and plant osmotic stress *** stress or ABA-induced activation of OsCIPK1 is dependent on ***10 phosphorylates Thr-24 of OsCIPK1 in vitro,and this phosphorylation increases the activity of OsCIPK1 and positively regulates the function of OsCIPK1 in ABA responses and plant osmotic stress *** study suggests that OsCIPK1 is a direct phosphorylated substrate of SAPK10,and SAPK10-mediated phosphorylation of OsCIPK1 functions in ABA signaling and increases rice osmotic stress tolerance.

关键词： Rice ABA Osmotic stress OsCIPK1 SAPK10