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Structural behavior of F-in mould flux melt of CaO-SiO2-Al2 O3-Na2O-CaF2 system

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Journal of Iron and Steel Research International 2017年第11期24卷 1152-1158页

作者： Qiang Gao yi min Cheng-jun Liu mao-fa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic mineral(ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

The influence of fluorine on the structure of CaO Si（）e-Al2Oa Na2O-CaF2 continuous-casting-type slag was measured by Raman spectroscopy, and the degree of polymerization of mould flux and the structural behavior of F- in the melt were investigated by classifying and quantifying the structural species of F ions. The results exhibit that the main structural units of Si O tetrahedra are Q1, Q1 and Q2, and the actual measured number of non bridging oxygen ions in the [SiO4 ]-tetrahedra （denoted by NBO/T） in creases from 2. 73 to 3.44 with increasing the molar ratio of F to （F＋O）（denoted by XF/X（F-O ） from 0.06 to 0. 19. It means that the degree of polymerization o1 meh structure decreases with an increase in XE/X（F＋O）. In addition, most of F- ions were distributed in Si-O tetrahedra and Al-O tetrahedra. With increasing XF/X（F＋O）, the complex structural units Al-Otetrahedra are gradually replaced hy discrete structural units A1F4 because of the breakage of Al-O bonds in Al-Otetrahedra by F ions, and the SiO （bridging oxygen） bonds of SiO tetrahedra are broken to form [SiOnF1-n]-tetrahedra by F ions coordinating with Si4 ＋ .

关键词： Mould flux F- ion Melt structure Polymerization degree

Effect of continuous casting speed on mold surface flow and the related near-surface distribution of non-metallic inclusions

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International Journal of minerals,Metallurgy and Materials 2019年第2期26卷 186-193页

作者： Peng Fei yi min Cheng-jun Liu mao-fa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic mineral ((ministry of Education)) School of Metallurgy Northeastern University Key Laboratory for Ecological Metallurgy of Multimetallic mineral (ministry of Education)

For the control of surface defects in interstitial-free(IF) steel, quantitative metallographic analyses of near-surface inclusions and surface liquid flow detection via the nail-board tipping method were conducted. The results show that, at casting speeds of 0.8 and 1.0 m/min, a thin liquid mold flux layer forms and non-uniform floating of argon bubbles occurs, inducing the entrainment and subsequent entrapment of the liquid flux; fine inclusion particles of Al_2O_3 can also aggregate at the solidification front. At higher casting speeds of 1.4 and 1.6 m/min, the liquid mold flux can be entrained and carried deeper into the liquid steel pool because of strong level fluctuations of the liquid steel and the flux. The optimal casting speed is approximately 1.2 m/min, with the most favorable surface flow status and, correspondingly, the lowest number of inclusions near the slab surface.

关键词： non-metallic inclusions distribution casting speed surface flow

奥曲肽治疗肝硬化门静脉高压食管胃底静脉曲张急性出血的多中心对照研究

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世界华人消化杂志 2005年第21期13卷 2570-2573页

作者：朱长清董胜翔茅益民曾民德蒋义斌许建明田德安刘吉勇徐三平孙樱罗和生王炳元上海第二医科大学附属仁济医院急诊科上海市200127 上海第二医科大学附属仁济医院消化内科上海市200127 复旦大学附属华山医院消化内科上海市200040 安微医科大学第一附属医院消化内科安徽省合肥市230022 华中科技大学同济医学院附属同济医院湖北省武汉市430030 山东省立医院山东省济南市250021 青岛市立医院山东省青岛市266011 武汉大学人民医院湖北省武汉市430060 中国医科大学附属第一医院辽宁省沈阳市110001

目的:与善宁对照,评价国产醋酸奥曲肽注射液治疗肝硬化门静脉高压食管胃底静脉曲张急性出血的疗效和安全性.方法:采用随机、双盲、多中心、阳性药物平行对照的方法治疗肝硬化食管胃底静脉曲张急性出血.在基础治疗(禁食、输液、输血、对... 详细信息

目的:与善宁对照,评价国产醋酸奥曲肽注射液治疗肝硬化门静脉高压食管胃底静脉曲张急性出血的疗效和安全性.方法:采用随机、双盲、多中心、阳性药物平行对照的方法治疗肝硬化食管胃底静脉曲张急性出血.在基础治疗(禁食、输液、输血、对症处理)的基础上,试验组70例将试验药醋酸奥曲肽注射液溶于生理盐水中,以50mg/h的速度连续滴注48h.对照组66例同样用善宁治疗并评估和比较其疗效及安全性.结果:治疗第1,2天和停药后24h,两组呕血次数和呕血量、黑便次数和黑便量也均显著减少,组内比较均有显著的统计学差异(P0.05).两组治疗后生命体征如心率、收缩压、舒张压以及患者的恶心、头晕、心悸、出汗、口渴症状均明显改善(P0.05).两组患者治疗后的不良反应分别为1.43%和1.52%,也无显著性差异(P>0.05).治疗后试验组总有效率为97.1%,与对照组的92.4%相似(P=0.2223).结论:奥曲肽治疗肝硬化门静脉高压食管胃底静脉曲张出血的疗效和安全性与善宁相当.

关键词：醋酸奥曲肽善宁硬化食管胃底静脉曲张急性出血疗效安全性

Assessment of landslide susceptibility using DBSCAN-AHD and LD-EV methods

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Journal of Mountain Science 2022年第1期19卷 184-197页

作者： mao yi-min MWAKAPESA Deborah S LI yi-can XU Kai-bin NANEHKARAN Yaser A ZHANG mao-sheng School of Information Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Key Laboratory for Geo-hazards in Loess Area Xi’an 710054China Northwest Nonferrous Geological mining Group Limited Company Xi’an 710054China

Landslide susceptibility assessment plays a vital role in understanding landslide information in advance and taking preventive as well as control measures. The need to initially specify the number of clusters, difficulty in handling noise and quantifying rainfall data, limits the application of traditional clustering models in landslide susceptibility assessment which then lowers their performance accuracy. Thus, to overcome these limitations, this study proposed an improved clustering algorithm titled the DBSCAN-AHD algorithm, which combines the traditional DBSCAN(Density Based Spatial Clustering of Application with Noise) algorithm and an Adaptive Hausdorff Distance(AHD) for landslide susceptibility modeling. Firstly, AHD was introduced to the traditional DBSCAN to quantify rainfall. Then,the DBSCAN-AHD grouped the mapping units with similar topology and geology characteristics into subclasses without specifying the number of clusters in advance for its ability to handle noise in the ***, the LD-EV(landslide density or eigenvalues) approach was introduced to obtain the susceptibility levels using K-means algorithm. Finally,to verify the model’s performance, statistical indices and the area under the curve(AUC) were applied and compared to the traditional DBSCAN, KPSO, Kmeans and Hierarchical Clustering algorithms,whereby, the proposed model outperformed the others. Also, the obtained susceptibility map can provide references in taking relevant preventive and control measures.

关键词： Landslide susceptibility DBSCAN Machine learning algorithm Uncertain data Clustering algorithm

Effects of extrusion parameters on physicochemical properties of flaxseed snack and process optimization

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International Journal of Agricultural and Biological Engineering 2015年第5期8卷 121-131页

作者： Wu min Liu yi Wang Lijun Li Dong mao Zhihuai College of Engineering China Agricultural UniversityBeijing 100083China Engineering Research Center for Modern Agricultural Equipment&Facilities Ministry of EducationBeijing 100083China College of Food Science and Nutritional Engineering China Agricultural UniversityBeijing 100083China

In order to optimize the extrusion process of flaxseeds snacks,the influence of different extrusion conditions on flaxseed production were studied by using the general four-factor quadratic designs of rotary combination and response surface methodology(RSM).Four extrusion conditions,the extrusion temperature(100-160°C),screw speed(60-180 r/min),feeding speed(18.35-54.95 kg/h)and moisture content(14%-30%w/w)were used as variables to detect the change of in vitro protein digestibility,expansion index,bulk density and texture(hardness and brittleness)of extruded *** superimposed RSM contour map,it was found that the optimum extrusion conditions could be obtained at feed composition with flaxseed content of 20%,moisture content of 17.37%-22.43%,extrusion temperature of 134.3-156.1°C,screw speed of 114-165.7 r/min and feeding speed of 34.38-45.95 kg/h,***,the composition and content of fatty acid in flaxseed-maize mixture changed rarely after extruded process,which indicated that extrusion had little impact on fatty *** the optimum extrusion conditions,the flaxseed-maize blends can be extruded into acceptable snack foods.

关键词： flaxseed extrusion optimization physicochemical property in vitro digestibility

Charge storage mechanism of MOF-derived Mn2O3 as high performance cathode of aqueous zinc-ion batteries

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Journal of Energy Chemistry 2021年第1期30卷 277-283,I0009页

作者： min mao Xingxing Wu yi Hu Qunhui Yuan Yan-Bing He Feiyu Kang Tsinghua Shenzhen International Graduate School Division of Energy&EnvironmentTsinghua UniversityShenzhen 518055GuangdongChina Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Advanced Welding and Joining and School of Materials Science and EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055GuangdongChina

Aqueous Zinc-ion batteries(ZIB) are attracting immense attention because of their merits of excellent safety and quite cheap properties compared with lithium-ion batteries(LIB).Manganese oxide is one of the most important cathode materials of *** this paper,α-Mn2O3 used as cathode of ZIB is synthesized via Metal-Organic Framework(MOF)-derived method,which delivers a high specific capacity of225 mAh g^(-1) at 0.05 A g^(-1) and 92.7 mAh g^(-1) after 1700 cycles at 2 A g^(-1).The charge storage mechanism of α-Mn2O3 cathode is found to greatly depend on the discharge current *** lower current density discharging,the H+ and Zn2+ are successively intercalated into the α-Mn2O3 before and after the "turning point" of discharge voltage and their discharging products present obviously different morphologies changing from flower-like to large plate-like *** a higher current density,the low-voltage plateau after the turning point disappears due to the decrease of amount of Zn2+ intercalation and the H+intercalation is dominated in α-Mn2 *** study provides significant understanding for future design and research of high-performance Mn-based cathodes of ZIB.

关键词： Zinc ion batteries α-Mn2O3 Metal-organic framework(MOF) Charge storage mechanism

Effect of Mg Addition on Nucleation of Intra-granular Acicular Ferrite in Al-killed Low Carbon Steel

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Journal of Iron and Steel Research International 2016年第5期23卷 415-421页

作者： Xiao-bing LI yi min Zhe YU Cheng-jun LIU mao-fa JIANG Key Laboratory for Ecological Metallurgy of Multimetallic mineral(ministry of Education) Northeastern University

To verify the formation behaviors and mechanisms of intra-granular acicular ferrite（ IAF） grains nucleated by Mg-Al-O in low carbon steel,the steels containing different Mg contents were refined in a vacuum induction furnace. The effect of Mg addition on the formation of IAF structure in Al-killed low carbon steel was investigated by optical microscope（ OM） and scanning electron microscope with energy dispersive X-ray spectroscope（ SEM-EDX）. It reveals that the IAFs are only detected in Mg-added steels,and the volume fraction of IAF increases with the Mg concentration from 8 × 10^（-6） to 26 × 10^（-6）. It shows that not only the MgO-Al_2O_3-MnS and MgO-Al_2O_3-P_2O_5 particles are the effective nucleation sites for IAF,but also the pure MgO·Al_2O_3 phase can promote the ferrite nucleation. A Mn-depletion zone（ MDZ） is characterized adjacent to the MgO-Al_2O_3-MnS,which is believed to be one of the possible mechanisms to explain the IAF nucleation. The MDZ around the MgO-Al_2O_3-MnS inclusion would be induced by the Mn S precipitation on the inclusion. It seems that the ability of Mg-containing inclusions to induce the nucleation of ferrite might be attributed to a new mechanism,i. e.,the Prich zone formed on a few Mg-Al-O inclusions might be another factor for promoting the IAF formation.

关键词： low carbon steel inclusion magnesium intra-granular acicular ferrite Mn-depletion zone

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北师大版初中数学新教材的特色及变化分析

教学与管理 2025年第1期 44-48页

作者：常海斌宁依敏首都师范大学教育学院北京100048 华东师范大学数学科学学院上海200241

深刻理解和准确解读教材是有效使用教材的前提。北师大版初中数学新教材遵循“教育本位”的教材编写理念,在章首语、栏目设置、问题解决、习题设计和素材选取上各具特色;教材整体采用跨领域混编、螺旋式上升和小结整合式的编写模式,着... 详细信息

深刻理解和准确解读教材是有效使用教材的前提。北师大版初中数学新教材遵循“教育本位”的教材编写理念,在章首语、栏目设置、问题解决、习题设计和素材选取上各具特色;教材整体采用跨领域混编、螺旋式上升和小结整合式的编写模式,着重凸显课程内容的结构化和认知过程的进阶性;四个学习领域以“研究对象”的形式进行内容整合,具有重视代数推理、重构统计量的组合形式以及对综合与实践领域进行主题迭代和核心创变等变化。

关键词：初中数学新教材教材编写特色北师大版教材新教材变化分析

Copper-coated Porous Polyimide as Ultralight and Safe Current Collectors for Advanced LIBs

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Chinese Journal of Polymer Science 2024年第4期42卷 521-531页

作者： Cun-Sheng Liu Jun-Qi Hu Ting-Ting mao Song-yi Liao Ru-ming Feng yi-Dong Liu Yong-Gang min School of Materials and Energy Guangdong University of TechnologyGuangzhou510006China College of Chemistry and Chemical Engineering Zhongkai University of Agriculture and EngineeringGuangzhou510225China Shanwei Branch of Advanced Energy Science and Technology Guangdong Laboratory Shanwei516600China

Metallic copper is widely used as current collector(CC) for graphite anode of lithium-ion batteries(LIBs) due to its high electrical conductivity and electrochemical stability. However, the large volume density of commercial copper foil(~8.9 g·cm^(-3)) limits the increase of energy density of battery. Here, copper-coated porous polyimide(Cu@PPI) was prepared by vacuum evaporation as collector for the graphite anode. The sandwich structure connects the copper metal on both sides of the collector with excellent electrical conductivity. Compared to commercial Cu foil, Cu@PPI has lighter mass(≤3.9 mg for disc of 12 mm diameter versus 9.9 mg of ~10 μm Cu foil) and lower volume density(≤3.3 g·cm^(-3)). In addition, the porous structure allows of better adhesion of reactive substances and electrochemical properties than pure Cu foils. It is estimated that the energy density of Cu@PPI should be much higher than that of Cu foil. This strategy should be applicable for other current collectors.

关键词： Copper-coated Vacuum evaporation Porous polyimide(PPI) Current collector(CC) LIBs