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Solubility Product for CuS and Cu_2S in Iron

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Journal of Iron and Steel Research International 2010年第8期17卷 36-38页

作者： qi hai-quan YONG qi-long Kunming University of Science and Technology Kunming 650093YunnanChina Central Iron and Steel Research Institute Beijing 100081China

The solubility product formulae of CuS and Cu2S in ferrite and in austenite have been obtained via thermodynamic method,according to the formation energy of CuS and Cu2S and the solubility formulae of elements Cu and S in ferrite and in *** comparing the solubility products for CuS and Cu2S in iron,it is found that Cu2S instead of CuS should be precipitated in iron due to competitative precipitation,in the view of *** formulae of CuS and Cu2S deduced from thermodynamic method would play an important role in related theoretical research and practical production.

关键词： CuS Cu2S solubility product ferrite austenite

Interfacial Fluctuation Behavior of Steel/Slag in Medium-Thin Slab Continuous Casting Mold With Argon Gas Injection

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Journal of Iron and Steel Research International 2010年第4期17卷 5-11页

作者： YU hai-qi ZHU Miao-yong WANG Jun School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China Anshan Iron and Steel Co Anshan 114009 Liaoning China

The flow field of molten steel and the interfacial behaviour between molten steel and liquid slag layer in medium-thin slab continuous casting mold with argon gas injection were studied by numerical simulation, in which the effects of nozzle submergence depth and port angle, casting speed, and argon gas flow rate on the flow and the level fluctuation of molten steel were considered. The results show that the molten steel is jetted from the submerged en- try nozzle （SEN） with three ports into the mold and forms three recirculation zones including one upper recireulation zone and two lower recirculation zones. Argon gas injection results in a secondary vortex flow in the upper zone near the nozzle. For a given casting speed and argon gas flow rate, increasing the side port angle and submergence depth of nozzle can effectively restrain the steel/slag interracial fluctuation. Increasing the casting speed would prick up the level fluctuation. For a fixed casting speed, argon gas flow rate has a critical value, the interracial fluctuation with argon gas injection are stronger than the case without argon gas injection when the argon gas flow rate is less than the critical value, but when the argon gas flow rate exceeds the critical value, the level fluctuation is calmer than that without argon gas injection.

关键词： medium-thin slab mold argon gas injection steel/slag interface numerical simulation

Dynamic alterations in early intestinal development,microbiota and metabolome induced by in ovo feeding of L-arginine in a layer chick model

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Journal of Animal Science and Biotechnology 2020年第3期11卷 896-911页

作者： Dong Dai Shu-geng Wu hai-jun Zhang Guang-hai qi Jing Wang Laboratory of Quality&Safety Risk Assessment for Animal Products on Feed Hazards(Beijing)of the Ministry of Agriculture&Rural Affairs and National Engineering Research Center of Biological FeedFeed Research InstituteChinese Academy of Agricultural Sciences12 Zhongguancun South St.Haidian DistrictBeijing 100081China

Background:Prenatal nutrition is crucial for embryonic development and neonatal growth,and has the potential to be a main determinant of life-long *** the present study,we used a layer chick model to investigate the effects of in ovo feeding(IOF)of L-arginine(Arg)on growth,intestinal development,intestinal microbiota and *** treatments included the non-injected control,saline-injected control,and saline containing 2,6,or 10 mg Arg ***:IOF Arg increased early intestinal index and villus height,and enhanced uptake of residual yolk lipid,contributing to subsequent improvement in the early growth performance of *** Arg supplementation also increased the early microbialα-diversity,the relative abundance of Lactobacillales and Clostridiales,and decreased the relative abundance of Proteobacteria of cecum in ***,the shift of cecal microbiota composition and the colonization of potential probiotics were accelerated by IOF of ***,metabolomics showed that metabolisms of galactose,taurine-conjugated bile acids and lipids were modulated to direct more energy and nutrients towards rapid growth of intestine at the beginning of post-hatch when embryos received IOF of ***:Prenatal Arg supplementation showed beneficial effects on the early intestinal development,cecal microbiota and host metabolism of layer chicks,contributing to subsequent improvement in the early growth *** findings provide new insight into the role of IOF of Arg in the establishment of the gut microbiota of newly-hatched layer chicks,and can expand our fundamental knowledge about prenatal nutrition,early bacterial colonization and intestinal development in neonate.

关键词： Development In ovo feeding Intestinal microbiota L-arginine Layer chick Metabolomics

A linear complementarity model for multibody systems with frictional unilateral and bilateral constraints

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Acta Mechanica Sinica 2011年第4期27卷 587-592页

作者： hai-Ping Gao qi Wang Shi-Min Wang Li Fu Department of dynamics and control Beihang University 100191 Beijing China

The Lagrange-I equations and measure differential equations for multibody systems with unilateral and bilateral constraints are constructed. For bilateral constraints, frictional forces and their impulses contain the products of the filled-in relay function induced by Coulomb friction and the absolute values of normal constraint reactions. With the time-stepping impulse-velocity scheme, the measure differential equations are discretized. The equations of horizontal linear complementarity problems （HLCPs）, which are used to compute the impulses, are constructed by decomposing the absolute function and the filled-in relay function. These HLCP equations degenerate into equations of LCPs for frictional unilateral constraints, or HLCPs for frictional bilateral constraints. Finally, a numerical simulation for multibody systems with both unilateral and bilateral constraints is presented.

关键词： Coulomb friction Bilateral constraint Unilat-eral constraint - Horizontal linear complementarity problem(HLCP) Time-stepping impulse-velocity algorithm

Mechanism and simulation of droplet coalescence in molten steel

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International Journal of Minerals,Metallurgy and Materials 2017年第11期24卷 1251-1259页

作者： Bing Ni Tao Zhang hai-qi Ni Zhi-guo Luo Department of Metallurgical Technology Central Iron and Steel Research Institute School of Metallurgy Northeastern University

Droplet coalescence in liquid steel was carefully investigated through observations of the distribution pattern of inclusions in solidified steel samples. The process of droplet coalescence was slow, and the critical Weber number(We) was used to evaluate the coalescence or separation of droplets. The relationship between the collision parameter and the critical We indicated whether slow coalescence or bouncing of droplets occurred. The critical We was 5.5, which means that the droplets gradually coalesce when We ≤ 5.5, whereas they bounce when We > 5.5. For the carbonate wire feeding into liquid steel, a mathematical model implementing a combined computational fluid dynamics(CFD)–discrete element method(DEM) approach was developed to simulate the movement and coalescence of variably sized droplets in a bottom-argon-blowing ladle. In the CFD model, the flow field was solved on the premise that the fluid was a continuous medium. Meanwhile, the droplets were dispersed in the DEM model, and the coalescence criterion of the particles was added to simulate the collision-coalescence process of the particles. The numerical simulation results and observations of inclusion coalescence in steel samples are consistent.

关键词： mechanism simulation droplet collision coalescence molten steel

Effect of Kupffer cells on immune tolerance in liver transplantation

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Asian Pacific Journal of Tropical Medicine 2012年第12期5卷 970-972页

作者： Guang-Shun Chen hai-Zhi qi Second Xiangya Hospital of Central South University

Objective:To observe the effect of Kupfler cells on immune tolerance in liver transplantation. Methods:The rats were randomly divided into A,B and C groups.A group was sham operation *** donor rats of group B had intraperitoneal injection of 1 nmol Kuppffer cells every other day for three days before liver *** of group C were injected with equal *** rat liver transplantation models were established by modified Kamada’s two-cuff *** rats were sacrificed after 24 *** concentrations of ALT and AST in serum were measured with the biochemical *** level of IL-2 and TNF- a in serum were measured by ELISA *** apoptotic indexes were detected by immunohistochemical assay. Results:The concentration of ALT,AST,IL-1 and TNF- a in A,B and C groups were increased *** levels of group C were significantly higher than that of group B and A(P<0.05), and the levels of group B were significantly higher than that of group A(P<0.05).The apoptotic indexes of three groups were 3.40±0.37,14.70±2.54 and 26.33±3.65,respectively,with significant difference among three groups(P<0.05).Conclusions:Pretreatment with Kupfler cells can reduce liver injury and raise liver transplantation immune tolerance.

关键词： Kupffer cell Liver transplantation Immune tolerance

Phenotypic Tfh development promoted by CXCR5-controlled re-localization and IL-6 from radiation-resistant cells

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Protein & Cell 2015年第11期6卷 825-832页

作者： Xin Chen Weiwei Ma Tingxin Zhang LongyanWu hai qi Tsinghua-Peking Center for Life Sciences Tsinghua University Beijing 100084 China Laboratory of Dynamic Immunobiology Institute for Immunology School of Medicine Tsinghua University Beijing 100084 China

How follicular T-helper （Tfh） cells develop is incom- pletely understood. We find that, upon antigen exposure in vivo, both naive and antigen-experienced T cells sequentially upregulate CXCR5 and Bc16 within the first 24 h, relocate to the T-B border, and give rise to phenotypic Bcl6＋CXCR5＋ Tfh cells before the first cell division. CXCR5 upregulation is more dependent on ICOS costimulation than that of Bcl6, and early Bcl6 induction requires T-cell expression of CXCR5 and, presumably, relocation toward the follicle. This early and rapid upregulation of CXCR5 and Bcl6 depends on IL-6 produced by radiation-resistant cells. These results suggest that a Bcl6hiCXCR5hi phenotype does not automatically define a Tfh lineage but might reflect a state of antigen exposure and non-commitment to terminal effector fates and that niches in the T-B border and/or the follicle are important for optimal Bcl6 induction and maintenance.

关键词： Tfh CXCR5 Bcl6 radiation-resistant cell,IL-6

Multiphase Flow and Thermo-Mechanical Behaviors of Solidifying Shell in Continuous Casting Mold

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Journal of Iron and Steel Research International 2013年第3期20卷 6-17页

作者： ZHU Miao-yong CAI Zhao-zhen YU hai-qi School of Materials and Metallurgy Northeastern University

The metallurgical phenomena occurring in the continuous casting mold have a significant influence on the performance and the quality of steel *** multiphase flow phenomena of molten steel,steel/slag interface and gas bubbles in the slab continuous casting mold were described by numerical simulation,and the effect of electromagnetic brake（EMBR） and argon gas blowing on the process were *** relationship between wavy fluctuation height near meniscus and the level fluctuation index F,which reflects the situation of mold flux entrapment,was ***,based on a microsegregation model of solute elements in mushy zone with δ/γ transformation and a thermo-mechanical coupling finite element model of shell solidification,the thermal and mechanical behaviors of solidifying shell including the dynamic distribution laws of air gap and mold flux,temperature and stress of shell in slab continuous casting mold were described.

关键词： continuous casting mold multiphase flow heat transfer solidification numerical simulation

Numerical Analysis of Electromagnetic Field and Flow Field in High Casting Speed Slab Continuous Casting Mold With Traveling Magnetic Field

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Journal of Iron and Steel Research International 2010年第9期17卷 25-30页

作者： WANG Hong-dan ZHU Miao-yong YU hai-qi School of Metallurgy and Materials Engineering Chongqing University of Science and Technology Chongqing 401331 China School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China

In a continuous casting process, it is essential to prevent the surface defects which are caused by the mold powder entrapments. It is well known that the decrease in the molten steel flow velocity just under the free surface is one of the most effective methods for the prevention of mold powder entrapments. For this purpose, the electro-magnetic level stabilizer （EMLS） has been developed, which is applied to a low frequency alternating magnetic field moving from the narrow face of the mold to the mold center below the nozzle exits. In this study, the effect of the EMLS on the molten steel flow is investigated. Numerical simulation of the electromagnetic field and the molten steel flow in a mold were carried out. Simulation results indicate that, due to the electromagnetic force, the molten steel is forced to flow toward the magnetic field traveling direction in the region where the magnetic field is imposed. The molten steel flow is decelerated in proportion to the imposed electromagnetic force. Consequently, the molten steel flows toward the mold center near the free surface with a smaller imposed electromagnetic force, and it flows toward the nozzle at the nozzle side and toward the narrow face at the narrow face side with a larger imposed electromagnetic force. However, the magnitude of the electromagnetic force is decided by the current intensity and frequency, a suitable imposed electric current can be chosen to minimize the flow velocity and also the amount of mold powder entrapments.

关键词： high casting speed mold EMLS flow field numerical analysis