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Study on concentration and turbulence of solid-liquid FAE in dispersal process

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Defence Technology（防务技术） 2018年第6期14卷 657-660页

作者： Jia-chen Chen xin ma Qiu-ju ma China Zhongyuan Engineering Corporation Beijing 100191China China Ordnance Society Beijing 100089China College of Resources&Safety Engineering China University of Mining&Technology(Beijing)Beijing 100083China

This paper describes numerical simulation on dispersion of the solid-liquid mixed fuel driven by explosion load. A model used in numerical calculation for dispersion of solid-liquid mixed fuel was established in this study. The concentration and turbulent intensity in the multiphase cloud of the solidliquid mixed fuel were obtained by numerical simulation. It was found that the fuel concentration tended to be 0.15 kg/m^3, the turbulence intensity tended to be 7 in 90 ms. The numerical results agree with those measured in the experiment.

关键词： Solid-liquid mixed fuel Concentration Turbulence intensity Numerical simulation

High-purity Mg and Mg-1Ca alloys:Comparative assessment of the merits regarding degradation,osteogenesis,and biosafety for orthopedic applications

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Journal of materials Science & Technology 2023年第9期140卷 58-66页

作者： Baiyan Sui hua Lu xin Liu Jiao Sun Department of Dental materials Shanghai Biomaterials Research and Testing CenterShanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineCollege of StomatologyShanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai 200011China

High-purity magnesium(HP Mg)and Mg-1Ca,as representations of Mg-matrix implants produced by purifying and alloying,are employed in biomedical applications primarily because of their bioactivity and *** superiority of both degradation properties,the match between degradation and osteo-genesis in vivo,and biosafety are critical problems that will decide future purifying or alloying to construct Mg-based implants and promote clinical *** present study investigated the benefits and limitations of degradation behavior and biosafety of HP Mg and Mg-1Ca according to the electro-chemical experiment,hydrogen evolution test,immersion test,and in vivo bone implantation *** results indicated that due to its Mg 2 Ca phase,Mg-1Ca exhibited a considerably higher corrosion current density and hydrogen production than HP Mg in ***,HP Mg and Mg-1Ca display a favorable match between their degradation and the surrounding osteogenesis,resulting in no significant variation in degradation in vivo during 26 ***,the implantation and degradation of HP Mg and Mg-1Ca do not result in major organ dysfunction or pathological *** work is expected to lay the foundation for future clinical translation of Mg and Mg alloy orthopedic implants.

关键词： High-purity magnesium Mg-1Ca Microstructure Degradation in vitro and vivo Biosafety

Study of a background reconstruction method for the measurement of D-meson azimuthal angular correlations

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Nuclear Science and Techniques 2021年第6期32卷 63-69页

作者： Long ma xin Dong huan-Zhong huang Yu-Gang ma Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan University200433 ShanghaiChina Nuclear Science Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA University of California Los AngelesCalifornia 90095USA

We studied experimental background reconstruction methods for the measurement of the D-D correlation using PYTHIA *** like-sign(LS)and side-band(SB)background methods,which are widely used in the experimental measurements of single D-meson production yields,were deployed for correlation *** was found that the LS method,which describes the combinatorial background of single D^(0) meson yields,fails to reproduce the correlated background in the D^(0)-D^(0) correlation measurement,while the SB background method yields a good description of the background for both single D^(0) yields and the correlated background of the D^(0)-D^(0) correlation *** further examined the validity of the correlation methods under different signal-to-background ratios,providing direct references for experimental measurements.

关键词： Heavy flavor Azimuthal correlation PYTHIA

Reaction mechanisms between molten CaF2-based slags and molten 9CrMoCoB steel

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International Journal of Minerals,Metallurgy and materials 2020年第5期27卷 611-619页

作者： Lei-zhen Peng Zhou-hua Jiang xin Geng School of Metallurgy Northeastern UniversityShenyang 110819China

Investigating the reaction mechanism between slag and 9CrMoCoB steel is important to develop the proper slag and produce qualified ingots in the electroslag remelting(ESR) process. Equilibrium reaction experiments between molten 9CrMoCoB steel and the slags of 55 wt%CaF2–20 wt%CaO–3 wt%MgO–22 wt%Al2O3–xwt%B2O3(x = 0.0, 0.5, 1.0, 1.5, 2.0, 3.0) were conducted. The reaction mechanisms between molten 9 CrMoCoB steel and the slags with different B2O3 contents were deduced based on the composition of the steel and slag samples at different reaction times. Results show that B content in the steel can be controlled within the target range when the B2O3 content is 0.5 wt% and the FeO content ranges from 0.18 wt% to 0.22 wt% in the slag. When the B2O3 content is ≥1 wt%, the reaction between Si and B2O3 leads to the increase of the B content of steel. The additions of SiO2 and B2O3 to the slag should accord to the mass ratio of [B]/[Si] in the electrode, and SiO2 addition inhibits the reaction between Si and Al2O3.

关键词： 9CrMoCoB electroslag remelting B2O3 thermodynamic calculation reaction mechanism

Effects of Fe content on the microstructure and properties of CuN i10FeM n1 alloy tubes fabricated by HCCM horizontal continuous casting

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International Journal of Minerals,Metallurgy and materials 2016年第4期23卷 449-457页

作者： Yan-bin Jiang Jun Xu xin-hua Liu Jian-xin Xie Key Laboratory for Advanced materials Processing of the Ministry of Education University of Science and Technology Beijing Beijing Laboratory of Metallic materials and Processing for Modern Transportation University of Science and Technology Beijing

Heating-cooling combined mold（HCCM） horizontal continuous casting technology developed by our research group was used to produce high axial columnar-grained CuN i10 FeM n1 alloy tubes with different Fe contents. The effects of Fe content（1.08wt%–2.01wt%） on the microstructure, segregation, and flushing corrosion resistance in simulated flowing seawater as well as the mechanical properties of the alloy tubes were investigated. The results show that when the Fe content is increased from 1.08wt% to 2.01wt%, the segregation degree of Ni and Fe elements increases, and the segregation coefficient of Ni and Fe elements falls from 0.92 to 0.70 and from 0.92 to 0.63, respectively. With increasing Fe content, the corrosion rate of the alloy decreases initially and then increases. When the Fe content is 1.83wt%, the corrosion rate approaches the minimum and dense, less-defect corrosion films, which contain rich Ni and Fe elements, form on the surface of the alloy; these films effectively protect the α-matrix and reduce the corrosion rate. When the Fe content is increased from 1.08wt% to 2.01wt%, the tensile strength of the alloy tube increases from 204 MPa to 236 MPa, while the elongation to failure changes slightly about 46%, indicating the excellent workability of the CuNi10FeMn1 alloy tubes.

关键词： copper nickel alloys iron content casting segregation mechanical properties corrosion resistance

Bioinformatics analysis of structure and function in the MRP gene family and its expression in response to various drugs in Bursaphelenchus xylophilus

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Journal of Forestry Research 2021年第2期32卷 779-787页

作者： Jian Diao xin Hao Wei ma Ling ma College of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Heilongjiang University of Chinese Medicine Harbin 150000People’s Republic of China

Genes homologous to members of the MRP gene family in Caenorhabditis elegans are important in drug *** further explore the molecular mechanism of drug resistance in pine wood nematode(Bursaphelenchus xylophilus),we used bioinformatics approaches to analyze genomic data for *** and identified Bx-MRP *** predicted the structure and function of the genes and encoded *** bioinformatics programs to predict and analyze various properties of the predicted proteins,including hydrophobicity,transmembrane regions,phosphorylation sites,and topologically isomeric structures,of these Bx-MRP genes,we determined that they function in transmembrane *** the results of RT-qPCR,the Bx-MRP family members confer significant differential resistance to different drug *** treatment with different concentrations of emamectin benzoate,avermectin and matrine,the expression of each gene increased with increasing drug concentrations,indicating that the family members play a positive role in the regulation of multidrug resistance.

关键词： Bursaphelenchus xylophilus Bx-MRP gene family Gene and protein structure Bioinformatics Multidrug stress

CDM: Content Diffusion Model for Information-Centric Networks

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Journal of Computer Science & Technology 2021年第6期36卷 1431-1451页

作者： Bo Chen Liang Liu hua-Dong ma Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and TelecommunicationsBeijing 100876China School of Computer Science Beijing University of Posts and TelecommunicationsBeijing 100876China

This paper proposes the Content Diffusion Model(CDM)for modeling the content diffusion process in information-centric networking(ICN).CDM is inspired by the epidemic model and it provides a method of theoretical quantitative analysis for the content diffusion process in ***,CDM introduces the key functions to formalize the key factors that influence the content diffusion process,and thus it can construct the model via a simple but efficient ***,we derive CDM by using different combinations of those key factors and put them into several typical ICN scenarios,to analyze the characteristics during the diffusion process such as diffusion speed,diffusion scope,average fetching hops,changing and final state,which can greatly help to analyze the network performance and application design.A series of experiments are conducted to evaluate the efficacy and accuracy of *** results show that CDM can accurately illustrate and model the content diffusion process in ICN.

关键词： information-centric networking content diffusion modeling

Nonmetallic Inclusion Control of 350 km/h High Speed Rail Steel

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Journal of Iron and Steel Research International 2009年第3期16卷 20-26,36页

作者： ZHAO Ke-wen ZENG Jian-hua WANG xin-hua School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing100083 China Panzhihua Iron and Steel (Group) Co Panzhihua 617067 Sichuan China

Inclusion has an important effect on quality of high speed rail steel. In consideration of the lower acceptance percentage of the inclusion and its constraint against the requirement for large scale production of 350 km/h high speed rail steel in Panzhihua Iron and Steel （Group） Co,the technology of nonmetallic inclusion control for 350 km/h high speed rail steel was studied. An optimized model of the argon-blowing in ladle furnace （LF）,the control of the components of the ladle slag,and the technique of calcium treatment for the molten steel was brought forward. Using the researched technology,the removal ratio of the inclusion was increased and the components,distribution,and shape of the inclusion in the rail steel were changed,which resulted in a reduction in the average total oxygen content to 10.17×10^-6 and an increase in the comprehensive acceptance percentage of the nonmetallic inclusion from 48.21% to 98.1%. Test has shown that this metallurgical technology can meet the requirement for large scale production of 350 km/h high speed steel in Panzhihua Iron and Steel （Group） Co.

关键词： high Speed rail steel inclusion refining calcium treatment total oxygen content

Microstructure evolution of Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)amorphous alloy after semi-solid isothermal treatment

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China Foundry 2024年第3期21卷 287-294页

作者： xin-hua huang Jing-wen Pu Yong-xin Luo Yue-jun Ouyang School of material Electricity and Intelligent ManufacturingHuaihua UniversityHuaihua 330031HunanChina Hunan Renewable Aluminum Innovation Research Center Huaihua UniversityHuaihua 330031HunanChina

The as-cast amorphous Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)composites,comprising in situ formedβ-Ti ductile crystalline precipitates,were prepared by water cooled copper mold suction ***,the semi-solid composites were obtained after the as-cast composites were treated by semi-solid isothermal *** microstructure evolution and kinetics of the composites were *** show that the microstructures of both the as-cast and semi-solid composites comprise ofβ-Ti crystal phases and amorphous matrix *** and after treatment,the crystals evolve from fine granular or fine dendritic crystals to coarse *** the treatment temperature increasing or the time prolonging,the average crystal size gradually increases and the surface morphology of the crystals gradually becomes *** studying the microstructural evolution and dynamics during the isothermal treatment process,it is found that the final morphology ofβ-Ti crystals is influenced by the isothermal treatment temperature and time(t),and theβ-Ti evolution rate increases with an increase in treatment *** addition,a linear relationship was observed between the size of cubicβ-Ti crystals(D^(3))and t;the growth kinetics factor K is 3.8μm^(3)·s^(-1).As the K value closes to 4μm^(3)·s^(-1),it is inferred the morphology evolution ofβ-Ti crystals is a coarsening behavior controlled by the diffusion of solute elements.

关键词： Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14) amorphous matrix composites semi-solid as-cast microstructure