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International Journal of Minerals,Metallurgy and Materials 2017年第5期24卷 512-522页

作者： yong-qiang Chen hong-liang Zhao Cheng-yan Wang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Key Lab of Rare & Precious Metals Green Recycling and Extraction

The preparation of ferronickel alloy from the nickel laterite ore with low Co and high MgO contents was studied by using a pre-reduction-smelting method. The effects of reduction time, calcination temperature, quantity of reductant and calcium oxide (CaO), and pellet diameter on the reduction ratio of Fe and on the pellet strength were investigated. The results show that, for a roasting temperature > 800 A degrees C, a roasting time > 30 min, 1.5wt% added anthracite coal, 5wt% added CaO, and a pellet size of similar to 10 mm, the reduction ratio of Fe exceeds 70% and the compressive strength of the pellets exceeds 10 kg per pellet. Reduction smelting experiments were performed by varying the smelting time, temperature, quantity of reductant and CaO, and reduction ratio of Fe in the pellets. Optimal conditions for the reduction smelting process are as follows: smelting time, 30-45 min; smelting temperature, 1550A degrees C; quantity of reductant, 4wt%-5wt%; and quantity of CaO, 5wt%; leading to an Fe reduction ratio of 75% in the pellets. In addition, the mineral composition of the raw ore and that during the reduction process were investigated by process mineralogy.

关键词： pre-reduction smelting ferronickel alloy nickel laterite ore

Existence and Properties of Solutions for a Class of Fractional Differential Equations

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Acta Mathematicae Applicatae Sinica 2021年第3期37卷 477-484页

作者： yong-qiang XU Shu-hong CHEN Zhong TAN School of Mathematics and Statistics Minnan Normal UniversityZhangzhou 363000China School of Mathematical Sciences Xiamen UniversityXiamen 361005China

In this paper,we consider the initial value problem of a class of fractional differential ***,we obtain the existence and uniqueness of the solutions by using Picard’s method of successive *** we discuss the dependen... 详细信息

关键词： existence uniqueness fractional derivative equations

2-D NUMERICAL SIMULATION OF RADIONUCLIDE TRANSPORT IN THE LOWER YANGTZE RIVER

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Journal of Hydrodynamics 2012年第5期24卷 702-710页

作者： ZHANG Wan-shun ZHAO Yan-xin XU Yan-hong WANG yong-gui XU Gao-hong School of Resource and Environmental Science Wuhan University Wuhan 430079 China Bureau of Hydrology of Changjiang Water Resources Commission Wuhan 430010 China

The assessment of the radiological impact of the liquid discharges from nuclear power plants is a major issue for the envi- ronmental protection. In this study, a numerical model for the radionuclide transport in the aquatic environment is built, based on the hydrodynamic equations, including the complete set of Saint-Venant equations, the sediment transport equations, with consideration of several different particle sizes and the deposition and erosion of the suspended sediments, and the radionuclide transport equations The exchanges of radionuclides between water, suspended matter and bed sediments are described in terms of kinetic transfer coe- fficients. The model is used to simulate the transport of the radionuclides discharged from a planned nuclear power plant project to be sited along the lower Yangtze River. From the model results, one may see the detailed temporal-spatial evolution of the radio- nuclide contamination in the solution, in the suspended matter and in the bed sediments. The model can be used as a basic tool for studying the environmental impacts of the liquid discharges from nuclear facilities on a river system.

关键词： 2-D numerical model radionuclide Yangtze River sediment

Effect of Heat-Treatment Schedule on the Microstructure and Mechanical Properties of Cold-Rolled Dual-Phase Steels

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1141-1148页

作者： yong-Gang Deng hong-Shuang Di Jie-Cen Zhang State Key Laboratory of Rolling and Automation Northeastern University

Low-carbon （0.08 wt% C） steel has been subjected to three different heat treatments to obtain dual-phase steels with different microstructures. An understanding of structure-property was established through tensile tests, in conjunction with scanning electron microscope and transmission electron microscope. The results show that the steel after intermediate quenching （IQ） consisting of fine and fibrous martensite exhibited the intermediate strength, highest elongation and the best comprehensive performance of mechanical properties, whereas the steel subjected to intercritical annealing （IA） produced a network martensite along ferrite grain boundaries, having the lowest strength and intermediate elongation. Besides, step quenching （SQ） resulted in a coarse and blocky ferrite-martensite microstructure showing the worst mechanical properties of the three different heat-treatment conditions. The strain-hardening behavior was studied through the modified Crussard- Jaoul model, indicating two stages of strain-hardening behavior for all three samples. The highest magnitude of strain- hardening ability was obtained by IQ annealing routes. The analysis of the fractured surface revealed that ferrite/martensite interfaces are the most susceptible for microvoid nucleation. However, martensite microcracks were also observed in SQ sample, and the microvoids are nucleated within the ferrite grain in IA sample as well. The variations in strength, elongation, strain-hardening behavior and fracture mechanism of the steel with different heat-treatment schedules were further discussed in relation to the microstructural features.

关键词： Dual-phase steel Heat-treatment schedule Strain-hardening behavior Fracture mechanism

Centroid-based sifting for empirical mode decomposition

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 88-95页

作者： hong hong Xin-long WANG Zhi-yong TAO Shuan-ping DU Key Laboratory of Modern Acoustics and Institute of Acoustics Nanjing University Nanjing 210093 China State Key Laboratory of Ocean Acoustics Hangzhou Applied Acoustics Research Institute Hangzhou 310012 China

A novel sifting method based on the concept of the 'local centroids' of a signal is developed for empirical mode decomposition (EMD), with the aim of reducing the mode-mixing effect and decomposing those modes whose frequencies are within an octave. Instead of directly averaging the upper and lower envelopes, as suggested by the original EMD method, the proposed technique computes the local mean curve of a signal by interpolating a set of 'local centroids', which are integral averages over local segments between successive extrema of the signal. With the 'centroid'-based sifting, EMD is capable of separating intrinsic modes of oscillatory components with their frequency ratio ν even up to 0.8, thus greatly mitigating the effect of mode mixing and enhancing the frequency resolving power. Inspection is also made to show that the integral property of the 'centroid'-based sifting can make the decomposition more stable against noise interference.

关键词： Sifting Empirical mode decomposition (EMD) Mode mixing effect Frequency resolution Local centroids Noise resistance

Numerical Simulations of Heavy Rainfall over Central Korea on 21 September 2010 Using the WRF Model

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Advances in Atmospheric Sciences 2015年第6期32卷 855-869页

作者： Ui-yong BYUN Jinkyu hong Song-You hong Hyeyum Hailey SHIN Department of Atmospheric Sciences Yonsei University Korea Institute of Atmospheric Prediction Systems NCAR

On 21 September 2010, heavy rainfall with a local maximum of 259 mm d-1 occurred near Seoul, South Korea. We examined the ability of the Weather Research and Forecasting （WRF） model in reproducing this disastrous rainfall event and identified the role of two physical processes： planetary boundary layer （PBL） and microphysics （MPS） processes. The WRF model was forced by 6-hourly National Centers for Environmental Prediction （NCEP） Final analysis （FNL） data for 36 hours form 1200 UTC 20 to 0000 UTC 22 September 2010. Twenty-five experiments were performed, consisting of five different PBL schemes--Yonsei University （YSU）, Mellor-Yamada-Janjic （MYJ）, Quasi Normal Scale Elimination （QNSE）, Bougeault and Lacarrere （BouLac）, and University of Washington （UW）--and five different MPS schemes--WRF Single- Moment 6-class （WSM6）, Goddard, Thompson, Milbrandt 2-moments, and Morrison 2-moments. As expected, there was a specific combination of MPS and PBL schemes that showed good skill in forecasting the precipitation. However, there was no specific PBL or MPS scheme that outperformed the others in all aspects. The experiments with the UW PBL or Thompson MPS scheme showed a relatively small amount of precipitation. Analyses form the sensitivity experiments confirmed that the spatial distribution of the simulated precipitation was dominated by the PBL processes, whereas the MPS processes determined the amount of rainfall. It was also found that the temporal evolution of the precipitation was influenced more by the PBL processes than by the MPS processes.

关键词： heavy rainfall WRF model microphysics planetary boundary layer

Inhibitory Effect of the Extract of Phellodendron amurense Ruprecht Root on Collagen-Induced Arthritis in Mice

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Chinese Journal of Integrative Medicine 2017年第10期23卷 755-762页

作者： Hyo Won jung Kyung-Ho Kim yong-Ki Park Department of Herbology College of Korean Medicine Dongguk University Gyeongju (740-814) Republic of Korea Korean Medicine Research and Development Center Dongguk University Gyeongju (740-814) Republic of Korea Department of Acupuncture College of Korean Medicine Dongguk University Gyeongju (740-814) Republic of Korea

Objective： To investigate whether the dried root of Phellodendron amurense Ruprecht（Phellodendri cortex; PC） extract improves arthritic symptoms through anti-inflammatory and immune-modulatory effects in collagen-induced arthritis in mice. Methods： Rheumatoid arthritis（RA） was induced in male DBA/1 mice by immunization with type Ⅱ collagen（ColⅡ）. CIA mice were divided into 5 groups（n=10 per a group） with normal, CIA control, PC extract（50 mg/kg and 100 mg/kg）-treated, and meloxicam（50 mg/kg）-treated as the reference drug. The PC extract or meloxicam were administered orally in CIA mice once a day for 14 days after arthritis induction. Arthritic score, levels of anti-ColⅡ IgG2a antibody, prostaglandin E2（PGE2）, tumor necrosis factor（TNF）-α, and interleukin（IL）-17 in the sera of CIA mice were measured. Histopathological changes in the ankle joints of CIA mice were also analyzed by staining with hematoxylin and eosin（H and E）, safranin-O and immunohistochemistry using anti-TNF-α and anti-IL-17 antibodies. Results： The arthritic score was increased in CIA mice in a time-dependent manner, as were the serum levels of anti-ColⅡ IgG2a antibody, PGE2, TNF-α, and IL-17. However, the oral administration of PC extract at 50 and 100 mg/kg in CIA mice significantly decreased the arthritic scores, and the serum levels of anti-ColⅡ IgG2a, PGE2, TNF-α, and IL-17 compared with those in the CIA group（P〈0.05 or P〈0.01）. Furthermore, histopathological improvement of the joint architecture in CIA mice was observed after administration of PC extract. PC extract also significantly inhibited the expression of TNF-α and IL-17 in the joints of CIA mice by suppressing the expression of their m RNA and proteins. Conclusion： PC extract may improve the pathological progression of RA through the inhibition of joint destruction by synovial inflammation and immune-stimulation, therefore, it would be a potential anti-arthritic agent in RA.

关键词： Phellodendron amurense Phellodendri cortex collagen-induced arthritis anti-arthritic effect

Changes in brain activation patterns according to cross-training effect in serial reaction time task An functional MRI study

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Neural Regeneration Research 2013年第7期8卷 639-646页

作者： yong Hyun Kwon jung Won Kwon Ji Won Park Department of Physical Therapy Yeungnam College of Science & Technology Department of Physical Therapy College of Health Science Catholic University of Daegu

Cross-training is a phenomenon related to motor learning, where motor performance of the untrained limb shows improvement in strength and skill execution following unilateral training of the homologous contralateral limb. We used functional MRI to investigate whether motor performance of the untrained limb could be improved using a serial reaction time task according to motor sequential learning of the trained limb, and whether these skill acquisitions led to changes in brain activation patterns. We recruited 20 right-handed healthy subjects, who were randomly allocated into training and control groups. The training group was trained in performance of a serial reaction time task using their non-dominant left hand, 40 minutes per day, for 10 days, over a period of 2 weeks. The control group did not receive training. Measurements of response time and percentile of response accuracy were performed twice during pre- and post-training, while brain functional MRI was scanned during performance of the serial reaction time task using the untrained right hand. In the training group, prominent changes in response time and percentile of response accuracy were observed in both the untrained right hand and the trained left hand between pre- and post-training. The control group showed no significant changes in the untrained hand between pre- and post-training. In the training group, the activated volume of the cortical areas related to motor function （i.e., primary motor cortex, premotor area, posterior parietal cortex） showed a gradual decrease, and enhanced cerebellar activation of the vermis and the newly activated ipsilateral dentate nucleus were observed during performance of the serial reaction time task using the untrained right hand, accompanied by the cross-motor learning effect. However, no significant changes were observed in the control group. Our findings indicate that motor skills learned over the 2-week training using the trained limb were transferred to the opposi

关键词： neural regeneration neuroimaging cross-training effects motor skill learning cortical activation cerebellar activation serial reaction time task functional MRI response time response accuracy primary motor cortex dentate nucleus vermis grants-supported paper photographs-containingpaper neuroregeneration

Applications of Extended Hyperbolic Function Method for Quintic Discrete Nonlinear SchrSdinger Equation

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Communications in Theoretical Physics 2007年第3期47卷 474-478页

作者： ZHAO hong HAN Ji-Guang WANG Wei-Tao AN hong-yong School of Physical Science and Information Engineering Liaocheng University Liaocheng 252059 China

By using the extended hyperbolic function method, we have studied a quintic discrete nonlinear Schrodinger equation and obtained new exact localized solutions, including the discrete bright soliton solution, dark soliton solution, bright and dark soliton solution, alternating phase bright soliton solution, alternating phase dark soliton solution, and alternating phase bright and dark soliton solution, if a special relation is bound on the coefficients of the equation.

关键词： extended hyperbolic function method quintic discrete nonlinear Schr6dinger equation discretesolitons alternating phase

Impact of Mo/Ni alloying on microstructural modulation and low-temperature toughness of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1746-1762页

作者： Wei Liu hong-li Zhao Bing-xing Wang yong Tian State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

The high-strength low-alloy steel plates with varying Ni/Mo contents were manufactured using the thermos-mechanical control *** investigation was conducted to explore the effect of Ni/Mo microalloying on microstructure evolution and mechanical properties of the *** results revealed that the increase in Ni content from 1 to 2 wt.%reduced the transition temperature of ferrite and the growth range of ferritic grain was narrowed,which promoted grain *** optimized combination of grain size,high-angle grain boundaries(HAGBs),and martensite-austenite(M-A)islands parameter contributed to the excellent impact toughness of S1 steel at-100℃(impact absorbed energy of 218.2 J at-100℃).As the Mo increases from 0 to 2 wt.%,the matrix structure changes from multiphase structure to granular bainite,which increases the average effective grain size to~4.62 pm and reduces HAGBs proportion to~36.22%.With these changes,the low-temperature impact toughness of S3 steel is *** addition,based on the analysis of the characteristics of crack propagation path,it was found that M-A islands with low content(~2.21%)and small size(~1.76 pm)significantly retarded crack propagation,and the fracture model of M-A islands with different morphologies was further ***,correlation between behaviour of delamination and toughness was further analysed by observing delamination size and impact energy parameters.

关键词： High-strength low-alloy steel Microstructural regulation Ni addition Mo addition Crack propagation Low-temperature toughness