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Response Characteristics and Adiabatic heating during High Strain Rate for TRIP Steel and DP Steel

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Journal of Iron and Steel Research International 2015年第1期22卷 48-54页

作者： Yi GAO Chao XU Zhong-ping he Yan-lin he Lin LI School of Materials Science and Engineering Shanghai University

By using a static and high-speed material testing machine, tensile deformation behaviors of two kinds of Si- Mn TRIP （transformation induced plasticity） steels and DP （dual phase） steel were studied in a large range of strain rates （0.001-2000 s 1）. Temperature variation during adiabatic heating and the amount of retained austenite at fracture were measured by an infrared thermometer and an Xray stress analyser, respectively. The microstructure of steels was observed by optical microscopy （OM） and scanning electron microscopy （SEM） before and after tensile test. It was found from the experimental results that the tensile strength of these steels increased, and the fracture elonga- tion firstly decreased and subsequently increased, as the strain rate increased in the range ＂of 0.1 - 2000 s -1. The temperature raised during adiabatic heating of TRIP steel was in the range of 100- 300℃, while that of the DP steel was in the range of 100-220℃ . The temperature rise of these steels increased with increasing the strain rate, as well as the amount of the transformed retained austenite in TRIP steels. It was confirmed that austenite to martensite transformation is not suppressed by adiabatic heating.

关键词： strain rate TRIP steel adiabatic heating retained austenite

Solar X-ray and Extreme Ultraviolet Imager(X-EUVI)loaded onto China’s Fengyun-3E Satellite

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Light(Science & Applications) 2022年第2期11卷 149-150页

作者： Bo Chen Guang-Xing Ding Ling-ping he Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

The solar X-ray and Extreme Ultraviolet Imager(X-EUVI),which was developed by CIOMP,is China’s first space-based solar X-ray and Extreme Ultraviolet(EUV)imager;it has been loaded onto the Fengyun-3E Satellite,which is supported by the China Meteorological Administration(CMA),for solar *** commenced working on July 11,2021,and was used to obtain the first X-ray and EUV images in China.X-EUVI employs an innovation dual band design to monitor a much larger temperature range across the Sun,covering the 0.6–8.0 nm wavelength band of the X-ray region and the 19.5 nm band of the EUV region.

关键词： Extreme loaded Solar

Hybrid polymer electrolyte for Li–O_2 batteries

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Green Energy & Environment 2019年第1期4卷 3-19页

作者： Bojie Li Yijie Liu Xiaoyu Zhang ping he Haoshen Zhou Center of Energy Storage Materials & Technology College of Engineering and Applied Sciences National Laboratory of Solid State MicrostructuresCollaborative Innovation Center of Advanced Microstructures Nanjing University Energy Technology Research Institute National Institute of Advanced Industrial Science and Technology(AIST)

Li–O_2 batteries have attracted much attention because of their high specific energy. However, safety problem generated mainly from the flammable organic liquid electrolytes have hindered the commercial use of Li–O_2 batteries. One of the competitive alternatives is polymer electrolytes due to their flexibility and non-flammable property. Moreover, the hybrid polymer electrolyte with enhanced electrochemical properties would be achieved by incorporating inorganic filler, liquid plasticizer and redox mediator into the polymer. While most researches of the hybrid polymer electrolyte focused on Li-ion batteries, few of them took account into its application in Li–O_2 batteries. In this review, we mainly discuss hybrid polymer electrolytes for Li–O_2 batteries with different composition. The critical issues including conductivity and stability of electrolytes are also discussed in detail. Our review provides some insights of hybrid polymer electrolytes for Li–O_2 batteries and offers necessary guidelines for designing the suitable hybrid polymer electrolyte for Li–O_2 batteries as well.

关键词： Li–O2 battery Hybrid polymer electrolyte Inorganic filler Liquid plasticizer Redox mediator

Modeling of maize gross primary production using MODIS imagery and flux tower data

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 110-118,I0004,I0005页

作者： Li Shihua he ping Liu Baosheng Ni ping Han Xing School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China School of Resources and Environment Jilin Agricultural UniversityChangchun 130018China

Maize is one of the most important crops cultivated on the global *** estimation of maize Gross Primary Production(GPP)can provide valuable information for regional and global carbon budget *** site level to regional/global scales,GPP estimation depends on remote sensing or eddy covariance flux *** this research,the 8-day composite GPP of maize was estimated by Moderate Resolution Imaging Spectroradiometer(MODIS)and flux tower data at eight study sites using a Regional Production Efficiency Model(REG-PEM).The performance of the model was assessed by analyzing the linearly regression of GPP estimated from the REG-PEM model(GPPEST)with the GPP predicted from the eddy covariance data(GPPEC).The coefficient of determination,root mean squared error and mean absolute error of the regression model were *** uncertainties of the model are also discussed in this *** seasonal dynamics(phases and magnitudes)of the GPPEST reasonably agreed with those of GPPEC,indicating the potential of the satellite-driven REG-PEM model for up-scaling the GPP in maize ***,the maize GPP estimated by this model is more accurate than the MODIS GPP products(MOD17A2).In particular,MOD17A2 significantly underestimated the GPP of maize *** uncertainties in the REG-PEM model are mostly contributed by the maximum light use efficiency and the fraction of photosynthetically active radiation.

关键词： gross primary production maize light use efficiency MODIS remote sensing flux datagross primary production maize light use efficiency MODIS remote sensing flux data

SYNTheSIS OF HIGH MOLECULAR WEIGHT POLYISOBUTYLENE VIA CATIONIC POLYMERIZATION AT ELEVATED TEMPERATURES

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Chinese Journal of Polymer Science 2013年第8期31卷 1139-1147页

作者： Qiang Huang ping he Jue Wang 吴一弦 State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

A novel simple but effective initiating system of H2O/AlCl3/veratrole （VE） has been developed to synthesize high molecular weight polyisobutylene （PIB） at elevated temperatures via cationic polymerization of isobutylene （IB） in solvent mixture of hexane/methylene dichloride （n-hex/CH2Cl2 = 2/1, V/V）. VE played very important roles in decreasing cationicity of the growing chain ends, suppressing side reactions of chain transfer and termination during polymerization, leading to production of high molecular weight PIBs. PIBs with high yields, having very high weight-average molecular weight （Mw） of 1117000 and 370000 g/tool could be synthesized with H2O/AICl3/VE initiating system at VE concentration of 5.4 mmol/L at -80 and -60 ℃ respectively. Molecular weight of PIB increased remarkably with increasing VE concentration. The reaction order with respect to VE concentration was determined to be -3.52 via FTIR spectroscopy in combination with a diamond tipped attenuated total reflectance （ATR） immersion probe. The negative reaction order of VE was consistent with its retarding effect on IB polymerization by interacting with the propagating species. Molecular weight of PIB decreased with increasing polymerization temperature. The activation energy for polymerization degree （Eop） could be determined to be around -23 kJ/mol when VE concentration was 5.4 mmol/L or 6.4 mmol/L.

关键词： Isobutylene Molecular weight Cationic polymerization Polyisobutylene Kinetics.

Scheme for generating 1 nm X-ray beams carrying orbital angular momentum at the SXFEL

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Nuclear Science and Techniques 2020年第9期31卷 33-44页

作者： he-ping Geng Jian-Hui Chen Zhen-Tang Zhao Chinese Academy of Sciences Shanghai Institute of Applied PhysicsShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Chinese Academy of Sciences Shanghai Advanced Research InstituteShanghai 201210China

Optical vortices have the main features of helical wavefronts and spiral phase structures,and carry orbital angular *** special structure of visible light has been produced and studied for various *** notable characteristics of photons were also tested in the extreme-ultraviolet and X-ray *** this article,we simulate the use of a simple afterburner configuration by directly adding helical undulators after the SASE undulators with the Shanghai Soft X-ray FEL to generate high intensity X-ray vortices with wavelengths^1 *** to other methods,this approach is easier to implement,cost-effective,and more efficient.

关键词： X-ray Orbital angular momentum(OAM) Synchrotron light source Free-electron laser(FEL)

Unicyclic graphs with extremal Lanzhou index

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Applied Mathematics(A Journal of Chinese Universities) 2022年第3期37卷 350-365页

作者： LIU Qian-qian LI Qiu-li ZHANG he-ping School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000China

Very recently *** et al.[8]introduced a new topological index for a molecular graph G named Lanzhou index as∑_(u∈V(G))d_(u)d^(2)_(u),where d_(u)and d_(u)denote the degree of vertex u in G and in its complement *** index Lz(G)can be expressed as(n-1)M_(1)(G)-F(G),where M_(1)(G)and F(G)denote the first Zagreb index and the forgotten index of G respectively,and n is the number of vertices in *** turns out that Lanzhou index outperforms M_(1)(G)and F(G)in predicting the logarithm of the octanol-water partition coefficient for octane and nonane *** was shown that stars and balanced double stars are the minimal and maximal trees for Lanzhou index *** this paper,we determine the unicyclic graphs and the unicyclic chemical graphs with the minimum and maximum Lanzhou indices separately.

关键词： Lanzhou index unicyclic graph extremal graph Zagreb index forgotten index

A survey of high risk factors affecting retinopathy in full-term infants in China

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International Journal of Ophthalmology(English edition) 2012年第2期5卷 177-180页

作者： Li-Na Chen Xiao-ping he and Li-ping Huang Department of Ophthalmology Boai Hospital of Zhongshan Zhongshan 528000 Guangdong Province China

AIM: To investigate the possible relationship between the influencing factors occurring before and during birth in full-term infants and the outcome of retinopathy. METHODS: Totally 816 full-term infants admitted in the neonate intensive unit of Boai Hospital of Zhongshan between 1 May, 2008 and 30 June, 2011 were included in the study. Fundus examination was performed and evaluated individually on them at the age of 48 hours after delivery, 2 weeks and 1 month. Some possible risk factors happening prenatally or during delivery such as pregnant related hypertension, placenta previa, placental abruption etc, as well as some neonatal risk factors such as neonatal asphyxia, hypoxic-ischemic encephalopathy (HIE), low birth weight etc, were recorded and evacuated. Then the effect of the risk factors of full-term infants on retinopathy was studied. RESULTS: The incidence of retinal hemorrhage of full-term infants with prenatal pregnant related hypertension (PRH) of the mother (43.6%) was significantly higher than that of full-term infants without (8.0%). (Phe incidence of retinal hemorrhage of full-term infants with neonatal asphyxia and /or hypoxic-ischemic encephalopathy (HIE)(29.3%) was significantly higher than that of those without (15.7%), but correlation was not found between the severity of retina hemorrhage and the degree of hypoxic disease. A pale color of optic disc was associated with a low birth weight of full-term infant. Full-term infants with birth weigh-less than 2500g had a significant higher incidence of retinopathy than those with birth weight equal or more than 2500g( Phe main influencing factors which lead to retinopathy of high risk full-term infants are prenatal factors such as PRH, and some neonatal risk factors such as asphyxia, hypoxic-ischemic encephalopathy, and low birth weight.

关键词： full-term infant high risk factor retinopathy

Numerical simulation of 3D electromagnetic–thermal phenomena in an induction heated slab

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Journal of Iron and Steel Research International 2020年第4期27卷 420-432页

作者： he-ping Liu Xian-hui Wang Liang-ying Si Jian Gong Central Iron and Steel Research Institute Beijing 100081China Shougang Zhixin Qian’an Electromagnetic Material Co. Ltd.Qian’an 064404HebeiChina

A mathematical model was developed to get an insight into 3D electromagnetic–thermal phenomena in an induction heated steel slab with a large width/thickness ratio by solving a fully coupled Maxwell equations and energy conservation *** spatial heat radiation between the slab surface and the refractory wall in an induction furnace was *** electromagnetic induction and temperature distribution features inside the slab with time evolution were *** effects of electromagnetic induction parameters,thermal conductivity of the material and process parameters on the induction heating process were theoretically *** results show that the spatial distribution of induction heat generation inside the slab is *** high work frequency and the low heat conductivity of slab increase the non-uniformity of slab induction heating *** radiative heat loss and heat transfer between the slab and the metal parts used for holding the slab have an important effect on the slab surface *** is necessary to separately control the current input in the multi-layer coil windings along the height direction of furnace and adopt the multi-step heating strategies with time evolution to improve the homogenization of the slab temperature.

关键词： Slab Electromagnetic feld Induction heating Numerical simulation