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Reaction mechanism between Al2O3-MgO refractory materials and rare earth high-carbon heavy rail steel

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JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL 2024年第5期31卷 1153-1163页

作者： Wang, Yi Song, guang-jie Shen, Ping He, Jian-zhong zhang, Da-xian Fu, Jian-xun Shanghai Univ Ctr Adv Solidificat Technol CAST State Key Lab Adv Special Steel Sch Mat Sci & Engn Shanghai 200444 Peoples R China State Key Lab Baiyunebo Rare Earth Resources Res & Baotou 014030 Inner Mongolia Peoples R China Inner Mongolia Baotou Steel Union Co Ltd Baotou 014030 Inner Mongolia Peoples R China

Submerged entry nozzle (SEN) clogging is a major problem affecting the production quality of rare earth steel, and finding a suitable refractory outlet can significantly reduce production costs. To explore the relationship between refractory composition and interface interaction, unprotected coated Al2O3-MgO refractories and SiO2-coated Al2O3-MgO refractories were added to rare earth high-carbon heavy rail steel under laboratory conditions, and the Al2O3-MgO refractory was found to be more suitable. The results show that, from the epoxy resin side to the refractory side, the contour of the refractory interface reaction layer can be divided into two main layers: an iron-rich reaction layer and an iron-poor reaction layer. Calculations based on the spherical model suggest that the adhesion force is proportional to the size of the refractory particles and inclusions, and the same result applies to the surface tension. Controlling the inclusions at a smaller size has a specific effect on alleviating the erosion of refractories. Combined with the erosion mechanism of Al2O3-MgO refractories, the interface reaction mechanism between Al2O3-MgO refractories and molten steel was proposed, which provides ideas for solving SEN clogging.

关键词： Rare earth high-carbon heavy rail steel Al2O3-MgO refractory Adhesion Surface tension Interface interaction INCLUSIONS BEHAVIOR MICROSTRUCTURE AGGLOMERATION

Qian-Zheng-San promotes regeneration after sciatic nerve crush injury in rats

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Neural Regeneration Research 2019年第4期14卷 683-691页

作者： Zhi-Yong Wang Li-Hua Qin Wei-guang zhang Pei-xun zhang Bao-Guo Jiang Department of Anatomy and Histo-embryology School of Basic Medical Sciences Peking University Department of Trauma and Orthopedics Peking University People's Hospital

Qian-Zheng-San, a traditional Chinese prescription consisting of Typhonii Rhizoma, Bombyx Batryticatus, Scorpio, has been found to play an active therapeutic role in central nervous system diseases. However, it is unclear whether Qian-Zheng-San has therapeutic value for peripheral nerve injury. Therefore, we used Sprague-Dawley rats to investigate this. A sciatic nerve crush injury model was induced by clamping the right sciatic nerve. Subsequently, rats in the treatment group were administered 2 mL Qian-Zheng-San(1.75 g/mL) daily as systemic therapy for 1, 2, 4, or 8 weeks. Rats in the control group were not administered Qian-Zheng-San. Rats in sham group did not undergo surgery and systemic therapy. Footprint analysis was used to assess nerve motor function. Electrophysiological experiments were used to detect nerve conduction function. Immunofluorescence staining was used to assess axon counts and morphological analysis. Immunohistochemical staining was used to observe myelin regeneration of the sciatic nerve and the number of motoneurons in the anterior horn of the spinal cord. At 2 and 4 weeks postoperatively, the sciatic nerve function index, nerve conduction velocity, the number of distant regenerated axons and the axon diameter of the sciatic nerve increased in the Qian-Zheng-San treatment group compared with the control group. At 2 weeks postoperatively, nerve fiber diameter, myelin thickness, and the number of motor neurons in the lumbar spinal cord anterior horn increased in the Qian-Zheng-San treatment group compared with the control group. These results indicate that QianZheng-San has a positive effect on peripheral nerve regeneration.

关键词： nerve regeneration traditional Chinese medicine crush injury peripheral nerve regeneration nerve conduction velocity sciatic function index nerve injury nerve repair formula scorpion neural regeneration

Relationship between intestinal microbial dysbiosis and primary liver cancer

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Hepatobiliary & Pancreatic Diseases International 2019年第2期18卷 149-157页

作者： Lei zhang Yong-Na Wu Tuo Chen Cheng-Hui Ren xun Li guang-Xiu Liu Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Key Laboratory of Extreme Environmental Microbial Resources and Engineering of Gansu Province University of Chinese Academy of Sciences The First Clinical Medical College Lanzhou University The First Hospital of Lanzhou University Lanzhou University Key Laboratory of Biotherapy and Regenerative Medicine of Gansu Province

Background: Intestinal microbial dysbiosis is involved in liver disease pathogenesis. However, its role in primary liver cancer(PLC), particularly in hepatocarcinogenesis remains unclear. The present study aimed to study the changes in intestinal flora at various stages of PLC and clarify the relationship between intestinal microbes and PLC. Methods: Twenty-four patients with PLC(PLC group), 24 patients with liver cirrhosis(LC group), and 23 healthy control individuals(HC group) were enrolled from October 2016 to October 2017. Stool specimens of the participants were collected and the genomic DNA of fecal bacteria was isolated. High-throughput pyrosequencing of 16 S r DNA was used to identify differences in gut bacterial diversity among HC, LC, and PLC groups. We also analyzed the relationship between clinical factors and intestinal microorganisms in LC and PLC groups. Results: Diversity of Firmicutes tended to decrease from the HC to LC and PLC groups at the phylum level. Among species, Enterobacter ludwigii displayed an increasing trend in the PLC group, wherein the relative abundance of Enterobacter ludwigii in the PLC group was 100 times greater than that in the HC and LC groups. The ratio of Firmicutes/Bacteroidetes was significantly decreased with the disease progression. In addition, the linear discriminant analysis effect size method indicated that Clostridia were predominant in the gut microbiota of the HC group, whereas Enterococcaceae, Lactobacillales, Bacilli and Gammaproteobacteria may be used as diagnostic markers of PLC. Redundancy analysis showed a correlation between intestinal microbial diversity and clinical factors AST, ALT, and AFP. Veillonella showed a significant positive correlation with AFP in the PLC group, whereas Subdoligranulum showed a negative correlation with AFP. Conclusions: This study indicates that dysbiosis of the gut microbiota might be involved in PLC development and progression.

关键词： Gut microbiota Microbial dysbiosis Hepatocarcinogenesis 16S rDNA

Construction of Ionic Porous Organic Polymers(iPOPs)via Pyrylium Mediated Transformation

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Chinese Journal of Polymer Science 2020年第9期38卷 958-964,I0006页

作者： Shi-Yue zhang Wei-Tao Gong Wei-Dong Qu Xiao-Rong Deng Kai-xun Dong Shu-guang zhang Gui-Ling Ning State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China Engineering Laboratory of Boric and Magnesic Functional Material Preparative and Applied Technology Dalian 116024China

Two new ionic porous organic polymers(iPOPs)with different counter anions were successfully fabricated via well-known pyrylium mediated transformation into pyridinium.13C solid-state NMR,XPS,and FTIR were analyzed and confirmed the formation of pyridinium in the network.Containing charged and aromatic networks,both iPOPs exhibit a high affinity towards toxic hexavalent chromium Cr(Ⅵ)ions.What is more,it has been demonstrated that both CO2 adsorption and Cr(Ⅵ)removal properties can be tuned by simply varying counter anions.

关键词： Ionic porous organic polymers Pyrylium CO2 adsorption Hexavalent chromium removal Different counter anions

Effect of Ti content on microstructures and mechanical properties of cast Al-2Li-2Cu-0.5Mg alloy

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China Foundry 2023年第3期20卷 179-188页

作者： You-jie Guo Dong-chen Yang Liang zhang Guo-hua Wu Yi-xiao Wang Pei-sen Li guang-xiao Ren Liang-bin Li xun-man Xiong National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanxi Jianghuai Heavy Industry Co. Ltd.Jincheng 048000ShanxiChina Jiangxi Ganfeng Lithium Co. LtdXinyu 338004JiangxiChina

Ti is regarded as one of the promising grain refiners in cast Al-Li-Cu alloys,but few research works have been done on its independent role.In this study,the effect of Ti on the microstructure evolution and mechanical properties of cast Al-2Li-2Cu-0.5Mg base alloy was investigated.The results revealed that the grains can be prominently refined with the increase of Ti addition.After adding Ti,high density TiB_(2)-Al_(3)Ti composite particles with a low lattice misfit form as heterogeneous nucleation sites for the α-Al matrix.δ’(Al3Li) and T_(1)(Al_(2)CuLi) precipitates that provide enhanced strength are dominated in the alloys after T6 aging treatment.The average size of both δ’ and half-width of δ’-precipitation free zone(PFZ) decreases gradually with the increase of Ti content.This is because the higher binding energy between Ti atoms and vacancies limits the diffusion efficiency of Li atoms,and thus results in a higher ductility.Additionally,no nano-sized Al_(3)Ti or core-shell structure of Al_(3)(Li,Ti) particles are found.The tensile property test results indicate that the Al-2Li-2Cu-0.5Mg alloy achieves optimal properties after aging at 175 °C for 32 h when 0.15wt.% Ti is added.It exhibits a yield strength of 352±5 MPa,an ultimate tensile strength of 423±6 MPa,and an elongation of(3±0.4)%.These findings are expected to offer a reliable theoretical guidance for the industrial composition design of the Al-Li-Cu series cast alloys.

关键词： cast Al-Li-Cu alloy Ti content grain refiner mechanical property microstructure

Infiltration behavior of sintering liquid on nuclei ores during low-titanium ore sintering process

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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 618-626页

作者： Dong-hui Liu Jian-liang zhang xun Xue guang-wei Wang Ke-jiang Li Zheng-jian Liu School of Metallurgy and Ecological Engineering University of Science and Technology Beijing

Sinter strength is dependent not only on the self-intensity of the residual rude and bonding phase but also on the bonding degree between them. The infiltration behavior of sintering liquid on nuclei ores influences the bonding degree, which ultimately determines the sinter strength. Infiltration tests were conducted using micro-sinter equipment. The infiltration area index of original liquid（IAO）, infiltration volume index of secondary liquid（IVS）, and sinter body bonding strength（SBS） were proposed to study the melt infiltration behavior. The results show that the IVS first increases and then decreases with increasing TiO2 content in adhering fines, whereas the IAO exhibits the opposite behavior. Compared with the original liquid, the secondary liquid shows lower porosity, smaller pores, and more uniform distribution. The SBS increases first and then decreases with increasing IAO and TiO2 content, and reaches a maximum when the IAO and TiO2 contents are approximately 0.5 and 2.0wt%, respectively. The SBS first increases and then tends to be stable with increasing IVS. The TiO2 content is suggested to be controlled to approximately 2.0wt% in low-titanium ore sintering.

关键词： titanomagnetite vanadium ore treatment ore sintering infiltration

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一种高功率因数谐振异步电机特性分析

海军工程大学学报 2023年第6期35卷 106-112页

作者：杨光马逊张志华中国航天科工集团有限公司磁悬浮与电磁推进技术总体部北京100143

传统交流异步电机仅在额定工况下可以维持较高的功率因数,而在其他各类工况下功率因数较低。针对这一问题,通过在绕线式异步电机转子/次级回路上串接电容来补偿异步电机的功率因数,提出了一种谐振异步电机。选择适当的电容容值及转差频... 详细信息

传统交流异步电机仅在额定工况下可以维持较高的功率因数,而在其他各类工况下功率因数较低。针对这一问题,通过在绕线式异步电机转子/次级回路上串接电容来补偿异步电机的功率因数,提出了一种谐振异步电机。选择适当的电容容值及转差频率,可以有效提高异步电机的功率因数,最高可以将功率因数提高至1。分析了谐振异步电机等效电路,基于等效电路对其功率因数特性进行了推导和分析,并采用一组电机参数将功率因数特性及转矩/推力特性与常规异步电机进行了对比分析。分析结果表明:在相同的电机参数下,所提出的谐振异步电机相较常规异步电机,在全速域具有高功率因数的特点;在输出同样的转矩/推力的情况下,谐振异步电机需要的定子电流更小、母线电压更低,适用于电磁推进/弹射的应用场景,可减小系统规模及建设成本,也可应用于一般的绕线式异步电机进行无功补偿。

关键词：直线电机绕线式异步电机无功补偿转子串电容等效电路全速域高功率因数

Basic characteristics of Australian iron ore concentrate and its effects on sinter properties during the high-limonite sintering process

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 991-998页

作者： Dong-hui Liu Hao Liu Jian-liang zhang Zheng-jian Liu xun Xue guang-wei Wang Qing-feng Kang School of Metallurgy and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Xuanhua Iron&Steel Group Co.Ltd. Xuanhua 075100China Beijing Shenwu Environment&Energy Technology Co. Ltd.Beijing 102200China

The basic characteristics of Australian iron ore concentrate (Ore-A) and its effects on sinter properties during a high-limonite sintering process were studied using micro-sinter and sinter pot methods. The results show that the Ore-A exhibits good granulation properties, strong liquid flow capability, high bonding phase strength and crystal strength, but poor assimilability. With increasing Ore-A ratio, the tumbler index and the reduction index (RI) of the sinter first increase and then decrease, whereas the softening interval (Delta T) and the softening start temperature (T (10%)) of the sinter exhibit the opposite behavior; the reduction degradation index (RDI+3.15) of the sinter increases linearly, but the sinter yield exhibits no obvious effects. With increasing Ore-A ratio, the distribution and crystallization of the minerals are improved, the main bonding phase first changes from silico-ferrite of calcium and aluminum (SFCA) to kirschsteinite, silicate, and SFCA and then transforms to 2CaO center dot SiO2 and SFCA. Given the utilization of Ore-A and the improvement of the sinter properties, the Ore-A ratio in the high-limonite sintering process is suggested to be controlled at approximately 6wt%.

关键词： iron ore concentrate limonite basic characteristics sinter properties sintering process

A One-dimensional Cobalt Coordination Polymer Based on Biphenyl-2,3,3',5'-tetracarboxylic Acid and N-donor Ancillary Ligands: Crystal Structure and Magnetic Property

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Chinese Journal of Structural Chemistry 2015年第10期34卷 1558-1564页

作者： LI Rong-Fang WANG Yu-Fang LIU Xin-Fang FENG xun zhang Xiao-Yu DU De-guang College of Chemistry and Chemical Engineering Luoyang Normal University Food and Bioengineering Department Henan University of Science and Technology Luoyang Huier Nano Science and Technology Co Ltd

Hydrothermal reactions of biphenyl-2,3,3A,5A-tetracarboxylic acid（H4bptc） with cobalt salt in the presence of 1,4-bis（2-pyridylmethyl）piperazin（bpmp） afforded one novel coordination polymer, namely, [Co（H2bptc）（bpmp）0.5（H2O）]n（1）. Its structure was established by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analysis. Complex 1 crystallizes in monoclinic, space group P21/c with a = 11.4839（11）, b = 16.6690（16）, c = 11.5559（11） A, V = 2201.8（4） A3, Mr = 539.35, Dc = 1.627 g/cm^3, μ（MoK α） = 0.841 mm-1, F（000） = 1108, Z = 4, the final R = 0.0309 and w R = 0.0705 for 4090 observed reflections（I 2σ（I））. Complex 1 displays a one-dimensional（1D） chain bridged by bpmp. Two carboxylic groups of H4 bptc ligand adopt μ01-η1：η1 and μ1-η1：η coordination modes to bridge adjacent Co（Ⅱ） ions together with bpmp ligand to give alternately arranged left- and right-handed helical chains. In addition, variable-temperature magnetic susceptibility measurements indicate that complex 1 shows weak antiferromagnetic interactions between the adjacent Co（Ⅱ） ions.

关键词： cobalt polymer diphenyl-2,3,3' 5'-tetracarboxylic acid 1,4-bis(2-pyridylmethyl)piperazin magnetic property