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Journal of Iron and Steel Research International 2008年第1期15卷 19-24页

作者： deng An-yuan wang En-gang HE Ji-cheng Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials Northeastern UniversityShenyang 110004 Liaoning China

To design a power source system and mold for electromagnetic soft-contact continuous casting process and to theoretically estimate the heat losses from the charges and the system power, the effect of structure parameters on system power and magnetic flux density distribution was calculated using finite element method. The results show that as for electromagnetic soft-contact continuous casting system with partial-segment type mold, the power consumption is much more than that with a full-segment type mold; about 62% of electric power is dissipated in the mold, and the effective acting range of magnetic field is relatively narrow. Optimizing mold structure is a crucial measure of remarkably reducing mold power consumption and saving electric energy. Increasing slit number, width, and length can remarkably increase the magnetic flux density in the mold and can reduce the electric energy consumption. Among structure parameters, slit number and slit width are relatively more effective to reduce energy consumption. For a round billet electromagnetic continuous casting system with diameter of 178 ram, the reasonable slit number, width, and length are about 24--32, 0. 5--1.0 mm, and 160 mm, respectively.

关键词： continuous casting soft-contact mold electromagnetic field electric power structure parameter

Meniscus Behavior in Electromagnetic Soft-Contact Continuous Casting Round Billet Mold

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Journal of Iron and Steel Research International 2006年第4期13卷 13-16页

作者： deng An-yuan wang En-gang HE Ji-cheng Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials NortheasternUniversity Shenyang 110004 Liaoning China

Using molten Pb-Sn-Bi alloy, the meniscus shape under high frequency magnetic field of φ100 mm round billet caster was investigated. The effect of some parameters on meniscus shape was studied. The results show that for a mold with 12 segments, the meniscus shape is relatively stable. With increasing power input, the menis- cus height increases with intensification of fluctuation. For the given caster, the reasonable power input is about 70 kW. The coil should be near to the top of mold and/or the initial meniscus should be near to the center of the coil. The lower the frequency, the higher is the meniscus height. With increasing frequency, the free surface is more flattened and meniscus becomes more stable. In practice, the power input should be increased simultaneously with frequency. The optimal frequency is about 20 kHz.

关键词： continuous casting soft-contact mold meniscus behavior high frequency magnetic field

Oscillation Characteristics of Molten Metal Free Surface Under Compound Magnetic Field

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Journal of Iron and Steel Research International 2011年第5期18卷 25-30,37页

作者： deng An-yuan wang En-gang XU Yong-yi ZHANG Xing-wu HE Ji-cheng Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials Northeastern UniversityShenyang 110004LiaoningChina

The free surface waves of a molten low-melting point Sn-32%Pb-52%Bi alloy under the imposition of an AC and a static magnetic field were visualized and recorded by use of a laser displacement sensor and a high speed video camera. The Fourier analysis method was used to analyze the oscillation characteristics. The results show that at the center of the free surface,the azimuthal and radial oscillation mode can be found simultaneously owing to AC magnetic field. With increasing coil current intensity,the amplitude and the main frequencies of the oscillations increase,and the azimuthal fluctuation at the center of the free surface is also enhanced. The fluctuation characteristics are closely related to the turbulent flow induced by the alternating electromagnetic force. A series of regular traveling waves can be observed on free surface,and the main frequencies of oscillations at three-phase points decrease owing to superposing AC and static magnetic field. The static magnetic field can remarkably control the unstable swinging behavior of free surface. With increasing static magnetic flux density,the amplitude of oscillations at the center of free surface decreases firstly,and then increases,but the fluctuation amplitude at the triple-phase point always reduces and keeps within 1 mm,and the azimuthal waves at the center of free surface are weakened. Especially at 1.44 T,the radial waves are dominant. The static magnetic flux density should be controlled in an appropriate range to obtain more stable free surface. With compound magnetic field,even if the static magnetic flux density is above 1.0 T,the free surface still vibrates with lower amplitude and dominant frequency.

关键词： continuous casting compound magnetic field free surface fluctuation

Synthesis and Biological Activity of Philanthotoxin Analogs

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Chinese Chemical Letters 2006年第7期17卷 895-898页

作者： Yong An ZHANG Ke Zhong LIU deng yuan wang Yu Zhu wang Liang Jian QU Chang Jin ZHU Research Institute of Forest Ecology Environment and Protection CAE Beijing 100091 The College of Agronomy Xinjiang Agricultural University Urumqi 830052 Department of Applied Chemistry Beijing Institute of Technology Beijing 100081

The synthesis of four analogs of philanthotoxin is described. The preliminary bioassay showed that these compounds all had good insecticidal activities, and the compound 6a had the best killing effect.

关键词： PhTX synthesis biological activity

Phase equilibria of Fe_(3)O_(4)-Cr_(2)O_(3)-CaO system:experimental measurements and thermodynamic calculations

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Journal of Iron and Steel Research International 2025年第1期32卷 95-104页

作者： Ao Zhu Chen-ying Shi Pei-yuan Ni Teng-fei deng State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070HubeiChina College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083HunanChina Key Laboratory of Ecological Metallurgy of Multi-Metal Intergrown Ores of Education Ministry School of MetallurgyNortheastern UniversityShenyang 110819LiaoningChina

Understanding the phase equilibria of the Fe_(3)O_(4)-Cr_(2)O_(3)-CaO system is essential for the efficient recycling of stainless steel pickling *** isothermal section of this system at 1473 K under oxygen partial pressure of 0.15 Pa was *** experiments on the relevant binary systems were conducted using a combination of equilibrium-quenching techniques,X-ray diffraction,high-resolution transmission electron microscope,and electron probe *** systems were rigorously assessed using the CALPHAD(CALculation of Phase Diagram)method,incorporating the present experimental *** liquid phase was modeled using the ionic two-sublattice model,represented as(Ca^(2+),Cr^(3+),Fe^(2+))P(O_(2)^(-),Va,FeO_(1.5))Q,where Va represents vacancy,and P and Q denote the number of sites on the cation and anion sublattices,*** ensure electroneutrality,the values of P and Q adjust according to the composition of the *** this,the isothermal section of the Fe_(3)O_(4)-Cr_(2)O_(3)-CaO system at 1473 K under the specified oxygen partial pressure was obtained based on the thermodynamic parameters of the binary *** present experimental data and calculation results hold significant implications for the comprehensive recycling of stainless steel pickling sludge.

关键词： Fe_(3)O_(4)-Cr_(2)O_(3)-CaO system Ionic two-sublattice model Phase equilibria CALPHAD

Insect seedling herbivory is influenced by multiple factors, but the plant apparency theory is more supported than other hypotheses - A case study in a subtropical forest

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FOREST ECOSYSTEMS 2025年第1期12卷 1-10页

作者： yuan, Baozhu wang, Bo Anhui Univ Sch Resources & Environm Engn Hefei 230601 Peoples R China Anhui Univ Anhui Prov Key Lab Wetland Ecosyst Protect & Resto Hefei 230601 Peoples R China Anhui Shengjin Lake Wetland Ecol Natl Long term Sc Dongzhi 247230 Peoples R China

Insect herbivory is ubiquitous in various ecosystems, and directly influences the growth and survival of individual plants, especially during their vulnerable early life stages like the seedling phase. This, in turn, exerts a significant influence on forest community diversity and structure, as well as ecosystem function and stability. Notable variation in herbivory has been detected both among and within plant species. For decades, many hypotheses have been proposed to explain such variations, including both biotic and abiotic variables. However, most studies have considered only one or several of these hypotheses by focusing on a few potential variables, and their results were usually inconsistent;thus, the factors driving herbivory remain unclear. In this study, we examined leaf herbivory by insects of woody species seedlings in a subtropical forest in southwestern China over two seasons. In total, 24 potential variables that represented abiotic resource availability, characters of individual seedlings, conspecific and heterospecific species, and the whole seedling community were selected to test several commonly discussed alternative herbivory hypotheses. Overall, our findings showed that the plant apparency hypothesis was more supported than the other hypotheses in explaining insect seedling herbivory. Our results further indicated that the mechanisms and causes of insect herbivory are complex, multifactorial, species-specific and vary with seasons, indicating that there may be no uniform rules in explaining herbivory for all seedlings. Consequently, such complexity may play an important role in promoting species coexistence and biodiversity maintenance in seedling communities, which may further translate into the following generation of saplings or even adult communities. Changes in the community of insect herbivores and/or variables influencing insect herbivory, may disrupt stability of the original seedling community, thus affecting the regeneration and deve

关键词： Canopy openness Leaf size Plant animal interaction Plant apparency theory Seedling height Species richness

Exploring the diversity of dissolved organic matter(DOM)properties and sources in different functional areas of a typical macrophyte-derived lake combined with optical spectroscopy and FT-ICR MS analysis

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Journal of Environmental Sciences 2025年第1期147卷 462-473页

作者： Kun wang Haoyu Ren Shengwu yuan Xia Jiang Pengfei wang College of Water Sciences Beijing Normal UniversityBeijing 100875China National Engineering Laboratory of Lake Pollution Control and Ecological Restoration Chinese Research Academy of Environmental SciencesBeijing 100012China

Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication *** organic matter(DOM)was a huge carbon pool and its abundance,property,and transformation played important roles in the biogeochemical cycle and energy flow in lake *** this study,Lake Baiyangdian was divided into four distinct areas:Unartificial Area(UA),Village Area(VA),Tourism Area(TA),and Breeding Area(BA).We examined the diversity of DOM properties and sources across these functional *** findings reveal that DOM in this lake is predominantly composed of protein-like substances,as determined by excitation-emission matrix and parallel factor analysis(EEM-PARAFAC).Notably,the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and ***-resolution mass spectrometry(FT-ICR MS)unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds,suggesting that macrophytes significantly influence the material structure of *** properties exhibited specific associations with water quality indicators in various functional areas,as indicated by the Mantel *** connections between DOM properties and NO_(3)-N andNH3-Nwere more pronounced in VA and BA than in UA and *** results underscore the viability of using DOM as an indicator for more precise and scientific water quality management.

关键词： Dissolved organic matter Fluorescence property Molecular composition Source

Steady-state and transient investigation of a small pressurized water reactor ACPR50S for different ATFs based on Bamboo-C code

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Nuclear Science and Techniques 2025年第1期36卷 192-206页

作者： Kun Zhuang Ying-Zhen wang Li-Na deng Yong-Zhan wang Wen Shang Si-Peng wang Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Small modular reactors have received widespread attention owing to their inherent safety,low investment,and *** pressurized water reactors(SPWRs)have become important candidates for SMRs owing to their high technological *** the Fukushima accident,research on accident-tolerant fuels(ATFs),which are more resistant to serious accidents than conventional fuels,has gradually *** study analyzes the neutronics and thermal hydraulics of an SPWR(ACPR50S)for different ATFs,BeO+UO_(2)−SiC,BeO+UO_(2)−FeCrAl,U_(3)Si_(2)−SiC,and U_(3)Si_(2)−FeCrAl,based on a PWR fuel management code,the Bamboo-C deterministic *** the steady state,the burnup calculations,reactivity coefficients,power and temperature distributions,and control rod reactivity worth were *** transients of the control rod ejection accident for the two control rods with the maximum and minimum reactivity worth were *** results showed that 5%B-10 enrichment in the wet annular burnable absorbers assembly can effectively reduce the initial reactivity and end-of-life reactivity *** BeO+UO2−SiC core exhibited superior neutronic characteristics in terms of burnup and negative temperature reactivity compared with the other three cases owing to the strong moderation ability of BeO+UO_(2)and low neutron absorption of ***,the U_(3)Si_(2)core had a marginally better power-flattening effect than BeO+UO_(2),and the differential worth of each control rod group was similar between different *** the transient of a control rod ejection,the changes in the fuel temperature,coolant temperature,and coolant density were *** maximum difference was less than 10℃ for the fuel temperature and 2℃ for the coolant temperature.

关键词： ACPR50S Small pressurized water reactor ATF Steady Transient

Impacts of ENSO on wintertime total column ozone over the Tibetan Plateau based on the historical simulations of community Earth system model

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Earth and Planetary Physics 2025年第02期 424-434页

作者： XiaoWen yuan YuZhen wang Yang Li YuHao Liu WeiLing Xu LiZi wang RuiHan deng School of Atmospheric Sciences Chengdu University of Information Technology

The ozone over the Tibetan Plateau(TP) plays an important role in protecting the local ecology by absorbing ultraviolet solar rays. The El Ni?o-Southern Oscillation(ENSO), recognized as the strongest interannual climate phenomenon globally, can create ozone variations over the TP. Based on the historical experimental simulation results of two Community Earth System Models(i.e. CESM2-WACCM and CESM2-WACCM-FV2) that include the coupling process of stratospheric chemistry-radiation-dynamics, this study analyzes the impact of ENSO on the wintertime total ozone column(TCO) over the TP, as well as its physical processes, from 1979 to 2014. When compared to observations, the results show that the two models can basically simulate the spatial distribution of the climate state and standard deviation of the TP TCO. In the two models, CESM2-WACCM performs better. During the winter when the ENSO signal is strongest, its warm phase, El Ni?o, cools the tropospheric temperature over the TP by modifying the atmospheric circulation, which induces a decrease in the tropopause height. Such decreases in the tropopause height are responsible for the TP TCO increase. The cool phase La Ni?a is responsible for a TCO decrease over the TP, in a manner resembling the El Ni?o but with the opposite signal. Our results are consistent with previous observational analysis, and the relevant research provides valuable scientific insights for evaluating and improving the Earth System Model that incorporates the coupling process of stratospheric chemistry-radiation-dynamics.

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中国经济过度杠杆化分析:表现、逻辑与治理

当代财经 2018年第9期 15-25页

作者：邓寅王园园对外经济贸易大学国际经济研究院北京100029

过度杠杆化为中国经济持续增长带来重大风险,积极稳妥去杠杆成为当务之急。利用经济增长理论,将市场主体实施过度杠杆化的动机解释为"庞氏游戏",据此探讨"过度杠杆化是受经济增长模式转型更迭的影响而引发的资源错配"这一命题。引入Ram... 详细信息

过度杠杆化为中国经济持续增长带来重大风险,积极稳妥去杠杆成为当务之急。利用经济增长理论,将市场主体实施过度杠杆化的动机解释为"庞氏游戏",据此探讨"过度杠杆化是受经济增长模式转型更迭的影响而引发的资源错配"这一命题。引入Ramsey模型、Arrow干中学模型和Romer知识溢出模型,分析不同模型下产生过度杠杆化的可能性。结果表明,以外生技术进步为特征的旧增长模式及以内生技术积累为特征的新增长模式均会自发抑制过度杠杆化,但以新旧经济成分共存为特征的增长模式转型阶段可能产生资本利差进而激励过度杠杆化,并且不同经济成分间要素流动受限与信息不对称强化了该机制。

关键词：过度杠杆化庞氏游戏经济增长模式政府治理