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Comparison of sintering performance of typical specular hematite ores with distinct size distributions

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Journal of Iron and Steel Research International 2017年第10期24卷 1007-1015页

作者： Cong-cong Yang De-qing Zhu Ben-jing Shi Jian Pan li-ming Lu xiao-bo li Ya-ping Mo School of Minerals Processing&Bioengineering Central South UniversityChangsha 410083HunanChina CSIRO Mineral Resources Brisbane QLD 4069Australia Products&Technique Management Department Baosteel Zhanjiang Iron and Steel Co.Ltd.Zhanjiang 524000GuangdongChina Ironmaking Plant Wuhan Iron and Steel Company LimitedWuhan 430083HubeiChina

The sintering performance of three typical specular hematite ores（coarse SO-A,intermediate SO-B and ultrafine SO-C）was compared in an industrial ore blend through pilot-scale sinter pot *** effect of particle size of specular hematite ores on their granulation and sintering performance was *** with the coarse SO-A fine and ultrafine SO-C concentrate,the intermediate SO-B showed inferior granulation and sintering performance characterized with poorer bed permeability and productivity,lower sinter strength and higher fuel rates.A new material preparation method was hence proposed and verified at both pilot and industrial *** proposed method by mixing SO-B with a high amount of goethitetype iron ore fines was found to be an effective way in improving the granulation and assimilative characteristics of ore blend comprising 31%intermediate SO-B,leading to improved sinter productivity and lowered fuel *** metallurgical properties and microstructure of sinters were also *** sinters obtained through the proposed preparation method were generally stronger and more reducible on account of better sinter structure with more relict hematite ultimately connected with needle-like silico-ferrite of calcium and aluminum and lower porosity.

关键词： Sinter Specularite Iron ore Size distribution Granulation Goethite

Effects of process parameters on morphology and distribution of externally solidified crystals in microstructure of magnesium alloy die castings

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China Foundry 2018年第2期15卷 139-144页

作者： Meng-wu Wu xiao-bo li Zhi-peng Guo Shou-mei Xiong Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of Technology School of Materials Science and Engineering Tsinghua University

During the cold-chamber high pressure die casting(HPDC) process, samples were produced to investigate the microstructure characteristics of AM60B magnesium alloy. Special attention was paid to the effects of process parameters on the morphology and distribution of externally solidified crystals(ESCs) in the microstructure of magnesium alloy die castings, such as slow shot phase plunger velocity, delay time of pouring and fast shot phase plunger velocity. On the basis of metallographic observation and quantitative statistics, it is concluded that a lower slow shot phase plunger velocity and a longer delay time of pouring both lead to an increment of the size and percentage of the ESCs, due to the fact that a longer holding time of the melt in the shot sleeve will cause a more severe loss of the superheat. The impingement of the melt flow on the ESCs is more intensive with a higher fast shot phase plunger velocity, in such case the ESCs reveal a more granular and roundish morphology and are dispersed throughout the cross section of the castings. Based on analysis of the filling and solidification processes of the melt during the HPDC process, reasonable explanations were proposed in terms of the nucleation, growth, remelting and fragmentation of the ESCs to interpret the effects of process parameters on the morphology and distribution of the ESCs in the microstructure of magnesium alloy die castings.

关键词： magnesium alloy high pressure die casting microstructure externally solidified crystals process parameters

Interfacial heat transfer behavior at metal/die in finger-plated casting during high pressure die casting process

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China Foundry 2017年第4期14卷 258-264页

作者： Wen-bo Yu Song liang Yong-you Cao xiao-bo li Zhi-peng Guo Shou-mei Xiong School of Materials Science and Engineering Tsinghua University Beijing 100084 China Laboratory for Advanced Materials Processing Technology Ministry of EducationTsinghua UniversityBeijing 100084China Beijing Star Airlines Mechanical and Electrical Equipment Company Beijing 100074China

Heat transfer at the metal-die interface has a great influence on the solidification process and casting structure. As thin-wall components are extensively produced by high pressure die casting process(HPDC), the B390 alloy finger-plate casting was cast against an H13 steel die on a cold-chamber HPDC machine. The interfacial heat transfer behavior at different positions of the die was carefully studied using an inverse approach based on the temperature measurements inside the die. Furthermore, the filling process and the solidification rate in different finger-plates were also given to explain the distribution of interfacial heat flux(q) and interfacial heat transfer coefficient(h). Measurement results at the side of sprue indicates that qmax and hmax could reach 9.2 MW·m^(-2) and 64.3 kW ·m^(-2)·K^(-1), respectively. The simulation of melt flow in the die reveals that the thinnest(T_1) finger plate could accelerate the melt flow from 50 m·s^(-1) to 110 m·s^(-1). Due to this high velocity, the interfacial heat flux at the end of T_1 could firstly reach a highest value 7.92 MW·m^(-2) among the ends of T_n(n=2,3,4,5). In addition, the q_(max) and h_(max) values of T_2, T_4 and T_5 finger-plates increase with the increasing thickness of the finger plate. Finally, at the rapid decreasing stage of interfacial heat transfer coefficient(h), the decreasing rate of h has an exponential relationship with the increasing rate of solid fraction(f).

关键词： high pressure die casting (HPDC) interfacial heat transfer behavior metal/die interface solidification speed solid fraction

Intestinal microflora molecular markers of spleen-deficient rats and evaluation of traditional Chinese drugs

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World Journal of Gastroenterology 2009年第18期15卷 2220-2227页

作者： Ying Peng Zhuo Wang xiao-bo li Chun-Fu Wu Jing-Yu Yang Yuan Lu School of Pharmacy Shanghai Jiao Tong University Shanghai 200030 China School of Pharmacy Shenyang Pharmaceutical University Shenyang 110016Liaoning Province China Northern Institute for Cancer Research Newcastle University Newcastle upon Tyne NE2 4AA United Kingdom

AIM:To find a rapid and efficient analysis method of gastrointestinal microflora in Pi-deficient(spleen-deficient) rats and to evaluate traditional Chinese ***:Enterobacterial repetitive intergenic consensus-PCR(ERIC-PCR) based assay was performed to examine changes of intestinal microflora in two Pi-deficienct animal models and to evaluate the efficacy of four traditional Chinese drugs as well as a probiotic recipe and another therapy in Pi-deficient ***:A molecular marker was identified for Pi-deficiency in *** pharmacodynamic evaluation system,including identified molecular markers(net integral area and abundance of DNA bands),Shannon's index for diversity of intestinal microflora,and Sorenson's pairwise similarity coefficient,was *** four major clinical recipes of traditional Chinese drugs for Pi-deficiency in rats,especially at their medium dose(equivalence to the clinical dose),produced more pronounced recovery activities in Pi-deficient rats,while higher doses of these recipes did not show a better therapeutic effect but some toxic effects such as perturbation deterioration of intestinal ***:both fingerprint analysis and identified marker can show Pi-deficiency in rats and its difference after *** identified molecular marker may be applied in screening for the active compounds both in relative traditional Chinese drugs and in pharmacodynamic study of Pi-deficiency in rats.

关键词： Pi-deficiency Enterobacterial repetitiveintergenic consensus-PCR Traditional Chinese medicine

Effect of anode area on the sensing mechanism of vertical GaN Schottky barrier diode temperature sensor

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Chinese Physics B 2022年第4期31卷 672-675页

作者： Ji-Yao Du xiao-bo li Tao-Fei Pu Jin-Ping Ao School of Automation and Electrical Engineering Shenyang Ligong UniversityShenyang 110159China Institute of Technology and Science Tokushima UniversityTokushimaJapan

Effect of anode area on temperature sensing ability is investigated for a vertical GaN Schottky-barrier-diode *** current-voltage-temperature characteristics are comparable to each other for Schottky barrier diodes with different anode areas,excepting the series *** the sub-threshold region,the contribution of series resistance on the sensitivity can be ignored due to the relatively small *** sensitivity is dominated by the current density.A large anode area is helpful for enhancing the sensitivity at the same current *** the fully turn-on region,the contribution of series resistance dominates the ***,a large series resistance degrades the temperature error and linearity,implying that a larger anode area will help to decrease the series resistance and to improve the sensing ability.

关键词： GaN temperature sensor Schottky contact vertical diode

An optimized numerical method to pre-researching the performance of solid-phase oxygen control in a non-isothermal lead–bismuth eutectic loop

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Nuclear Science and Techniques 2022年第3期33卷 77-88页

作者： xiao-bo li Rui-Xian liang Yi-Feng Wang Hui-Ping Zhu Fang liu Yang liu Cong li Hao Wu Feng-Lei Niu School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China

In the present work,a new transient calculation method for parameters that can be used to evaluate the ability of oxygen control in a non-isothermal lead-bismuth eutectic(LBE)loop with solid-phase oxygen control was *** incorporates the dissolution process of Pbo particles and the oxygen mass transfer process,and an optimized method was used for finding out the optimized oxygen mass transfer *** numerical terms,three mass transfer models were simultaneously applied,and comparisons of calculated and experimental results from the CRAFT loop indicated that the optimized calculation method and these new oxygen mass transfer models were correct and applicable to other LBE *** this calculation method,we aimed to optimize prediction of the distribution of oxygen and iron concentrations,time taken to establish the steady state of oxygen,and maximum dissolution/precipitation rates of corrosion products and corrosion depth across the entire LBE *** hope that this work will provide a potential reference for designing a more intelligent oxygen control system in the future.

关键词： LBE Solid-phase oxygen control Operating domain Operating model Corrosion depth Dissolution/precipitation

On the Relation Between Coronal Green line Brightness and Magnetic Fields Intensity

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Research in Astronomy and Astrophysics 2022年第7期22卷 128-138页

作者： Xue-Fei Zhang Yu liu Ming-Yu Zhao Teng-Fei Song Jing-Xing Wang xiao-bo li Zi-Han li Yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Yunnan Normal University School of Physics and Electronic InformationKunming 650000China

Two-dimensional(2 D) solar coronal magnetogram is difficult to be measured directly until *** the previous knowledge,a general relation has been noticed that the brighter green-line brightness for corona,the higher coronal magnetic field intensity may correspond *** try to further reveal the relationship between coronal green line brightness and magnetic field intensity,we use the 2 D coronal images observed by Yunnan Observatories Greenline Imaging System(YOGIS) of the 10 cm lijiang coronagraph and the coronal magnetic field maps calculated from the current-free extrapolations with the photospheric magnetograms taken by Helioseismic and Magnetic Imager(HMI) on board the Solar Dynamics Observatory(SDO) *** our analysis,we identified the coronal loop structures and construct two-dimensional maps of the corresponding magnetic field intensity in the plane of the sky(POS) above the *** derive the correlation coefficients between the coronal brightness and the magnetic field intensity for different heights of coronal *** further use a linear combination of a Gaussian and a quadratic profile to fit the correlation coefficients distribution,finding a largest correlation coefficient of 0.82 near 1.1 R(solar radii) where is almost the top of the closed loop *** the small closed loop system identified,the correlation coefficient distributions crossing and covering the loop are *** also investigate the correlation with extended heliocentric latitude zones and long period of one whole Carrington Rotation,finding again that the maximum correlation coefficient occurs at the same *** is the first time for us to find that the correlation coefficients are high(all are larger than 0.8) at the loop-tops and showing poor correlation coefficients with some fluctuations near the feet of the coronal *** findings indicate that,for the heating of the low-latitude closed loops,both DC(dissipation of currents) and AC(dissipation of Alfvé

关键词： Sun:magnetic fields Sun:corona Stars:coronae Sun:activity Sun:atmosphere Sun:coronal mass ejections(CMEs) Sun:fundamental parameters Sun:heliosphere Sun:UV radiation

Antibacterial Property of Cu Modified Stainless Steel by Plasma Surface Alloying

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Journal of Iron and Steel Research International 2012年第4期19卷 75-79页

作者： ZHANG Xiang-yu HUANG xiao-bo JIANG li MA Yong FAN Ai-lan TANG Bin Research Institute of Surface Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

Stainless steel（SS） is not recommended to be used in hospital environments for work surfaces and door furniture due to the lack of antibacterial *** this end,a novel SS surface modified layer with both a quick bacterial killing rate and relatively thick has been obtained by plasma surface alloying with *** microstructure,elements distribution and phase identification were analyzed by SEM,GDS,XRD and XPS.A spread plate method was adopted for evaluation of antibacterial property of specimens against Escherichia coli（***） and Staphylococcus aureus（***）.The experimental results demonstrate that the surface modified layer with the thickness of about 26 μm is uniform and *** layer is mainly composed of a mixture of pure Cu,expanded austenite phase and a few Fe3O4 *** Cu modified layer exhibits excellent antibacterial effects against *** and *** within 1 *** viable *** and *** was found after 3 h（100% killed）.The modified layer is relatively thick,hence it is expected that the Cu modified SS will have a durable antibacterial function

关键词： plasma alloying Cu antimicrobial AISI 304 stainless steel

Quinoline-based colorimetric chemosensor for Cu^(2+): Cu^(2+)-induced deprotonation leading to color change

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Chinese Chemical Letters 2014年第1期25卷 80-82页

作者： xiao-bo li Zhi-Gang Niu ling-ling Chang Men-Xia Chen En-Ju Wang School of Chemistry and Chemical Engineering Hainan Normal University

A quinoline-based colorimetric chemosensor （QDB） for Cu2＋ was synthesized by coupling quinoline-2- carbaldehyde with 4-（dimethylamino）benzohydrazide. Although most transition metal cations can cause redshiffs in the UV-vis spectrum of QDB, the response of the chemosensor for Cu2＋ can be easily distinguished because it exhibits the largest redshift together with a color change from colorless to red in response to Cu2＋. Other metal ions have no effect on the specific response of QDB to Cu2＋. The significant redshift and color change were attributed to Cu2＋-induced deprotonation of NH in the sensor.

关键词： Quinoline-based sensor Colorimetric sensor CopperDeprotonation