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Evolution of MnO–SiO2–Al_(2)O_(3)–MgO inclusions during heat treatment at 1100℃

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1221-1231页

作者： Xu-bo Lei jian-li li Qiang Zeng Hang-yu Zhu Yue Yu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina

To investigate the evolutionary behavior of the MnO–SiO_(2)–Al_(2)O_(3)–MgO inclusions during heat treatment,water quenched samples were isothermally held at 1100°C for 120 min in Ar and air atmosphere,and the obtaining samples were analyzed by X-ray diffraction,scanning electron microscopy and energy dispersive spectrometer.It showed that 3MnO·Al_(2)O_(3)·3SiO_(2)and MnO·SiO_(2)were detected in the 5 wt.%MgO system after isothermal holding in Ar atmosphere,while MgO·Al_(2)O_(3),MnO·SiO_(2)and Mn7O8·SiO4 were detected in air atmosphere.The evolutionary behavior of the 10,15 and 20 wt.%MgO systems after isothermal holding in different atmosphere were consistent.Oxygen affected the solid phase transformation of the low MgO content systems.The calculation results of FactSage 8.1 showed that MgO·Al_(2)O_(3)was formed in the 5 wt.%MgO system with air atmosphere.The solid phase transformation was accompanied by grain coarsening during the isothermal holding process.The differences in the solid phase transformation in different atmosphere of the 5 wt.%MgO system indicated that it was a gas-phase transport grain coarsening mechanism.The enrichment of Al element in the liquid phase region at the grain edges,the homogeneous distribution of Mg element and the disappearance of the liquid phase within the crystal revealed that other MgO content systems were liquid–solid transport grain coarsening mechanism.

关键词： Evolution Glassy phase Inclusion Heat treatment MgO·Al_(2)O_(3)

Soil Acidification and Heavy Metals in Urban Parks as Affected by Reconstruction Intensity in a Humid Subtropical Environment

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Pedosphere 2015年第1期25卷 82-92页

作者： HOU En-Qing XIANG Hui-Min li jian-li li Jiong WEN Da-Zhi Institute of Ecology and Environmental Sciences South China Botanical Garden Chinese Academy of Sciences Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical Garden Chinese Academy of Sciences University of Chinese Academy of Sciences Agricultural and Forestry Extension Centre of Nanhai District

Soil quality is a major concern in the management of urban parks. In this study, the soils at 0–3, 3–13, and 13–23 cm depths were sampled from six urban parks, differing in reconstruction intensity(mainly changes made during conversion of natural forests into parklands), in the Pearl River Delta, China to determine how reconstruction intensity influenced the extent of acidification and heavy metal levels in the soils of urban parks in a humid subtropical environment. High reconstruction intensity(HRI) was practiced in three parks and low reconstruction intensity(LRI) in three other parks. The LRI soils were strongly to extremely acidic(with low exchangeable Ca, Mg, and K concentrations) while the HRI soils were much less acidic. Both total and extractable concentrations of soil heavy metals were related to the specific management practices and age of the park, but did not differ significantly between LRI and HRI parks or among soil depths. Soil p H was significantly related to soil exchangeable cation concentrations and base saturation but was weakly related or unrelated to soil heavy metal levels. Our results suggest that high intensity but not low intensity reconstruction significantly reduces the extent of soil acidification in the urban parks in a humid subtropical environment.

关键词：土壤重金属含量城市公园土壤酸化湿润环境中亚热带低强度盐基饱和度阳离子浓度

Theoretical and Experimental on Carbon Dioxide Sequestration Degree of Steel Slag

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Journal of Iron and Steel Research(International) 2012年第12期19卷 29-32页

作者： li jian-li ZHANG Hui-ning XU An-jun CUI jian HE Dong-feng TIAN Nai-yuan State Key Laboratory of Advanced Metallurgy University o{ Science and Technology Beijing Beijing 100083 China Ningbo Iron and Steel Co Ltd Ningbo 315000 Zhejiang China

The limitation and experimental CO2 sequestration degree of steel slag is the focus. The theoretical and the practical COe sequestration degree was assessed under mild operating conditions. After calculation in theory, it can be found that the CO2 sequestration limitation degree for every kilogram steel slag is about 442 g when taking magne- sium into consideration, and the experimental CO2 sequestration degree for every kilogram slag is about 77 g, under the conditions that the liquid to solid ratio is 50 L/kg, CO2 flow is 0.5 L/min and the temperature of reaction is the ambient temperature. When solution NH4Cl and CHa COOH for experiments and other conditions keep the same, the actual potential CO2 sequestration for every kilogram slag is 69.3 g and 31.20 g respectively. Thus, optimization of process parameters like granularity of slag is necessary to enhance the carbon dioxide sequestration degree for steel slag.

关键词： steel slag calcium leaching CO2 sequestration limitation degree

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液氢储存低温绝热技术研究进展

科学技术与工程 2024年第14期24卷 5675-5689页

作者：李敬法陈志博郑度奎宇波张伟赵杰李建立北京石油化工学院机械工程学院并氢能研究中心北京102617 长江大学石油工程学院武汉430100 福建省锅炉压力容器检验研究院福州350008

液氢储存具有单位体积储氢密度高、长距离输送成本低等优势。但液氢储存是将氢气冷却到-253℃进行液化后储存在绝热容器中,故对储存容器的低温绝热性能要求极高。围绕液氢储存被动绝热和主动绝热技术,通过文献调研的方式回顾了当前液氢... 详细信息

液氢储存具有单位体积储氢密度高、长距离输送成本低等优势。但液氢储存是将氢气冷却到-253℃进行液化后储存在绝热容器中,故对储存容器的低温绝热性能要求极高。围绕液氢储存被动绝热和主动绝热技术,通过文献调研的方式回顾了当前液氢储存低温绝热技术的研究进展,介绍了不同绝热技术的原理,比较了不同绝热技术的适用范围,分析了目前不同绝热技术中存在的瓶颈问题和不足之处,总结了各绝热技术未来的发展趋势。为液氢储存低温绝热技术的发展提供参考。

关键词：液氢储存绝热技术被动绝热主动绝热

DCE-MRI血流动力学参数在高、低级别胶质瘤鉴别中的应用及其与分子生物学标记物水平的相关性

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川北医学院学报 2024年第2期39卷 177-181页

作者：李建丽张晓瑞李莹邯郸市中心医院CT/MR室河北邯郸056001

目的:探讨动态增强磁共振成像(DCE-MRI)血流动力学参数在高、低级别胶质瘤鉴别中的应用,分析其与分子生物学标记物水平的相关性。方法:选取86例脑胶质瘤患者为研究对象。以病理结果作为金标准,按WHO肿瘤分类标准,将其分为低级别组(n=41... 详细信息

目的:探讨动态增强磁共振成像(DCE-MRI)血流动力学参数在高、低级别胶质瘤鉴别中的应用,分析其与分子生物学标记物水平的相关性。方法:选取86例脑胶质瘤患者为研究对象。以病理结果作为金标准,按WHO肿瘤分类标准,将其分为低级别组(n=41)、高级别组(n=45),获得常规和动态增强MRI扫描参数数值,通过受试者工作特征曲线(ROC)分析DCE-MRI血流动力学参数对高、低级别胶质瘤的鉴别价值,Pearson分析各血流动力学参数与癌组织分子生物学标志物的相关性。结果:高级别组DCE-MRI血流动力学参数Ktrans、Kep、Ve水平均高于低级别组(P0.05);DCE-MRI血流动力学参数Ktrans、Kep、Ve联合检测鉴别高、低级别脑胶质瘤ROC曲线下面积(AUC)为0.927,高于单独检测AUC(0.822、0.803、0.785),敏感度为91.11%、特异度为80.49%(P<0.05);高级别组脑胶质瘤分子生物学标记物VEGF mRNA、Ki-67 mRNA表达水平高于低级别组(P<0.05);Pearson相关性分析显示,脑胶质瘤DCE-MRI血流动力学参数Ktrans、Kep、Ve水平与癌组织VEGF mRNA、Ki-67 mRNA表达水平正相关(r=0.522、0.415、0.323、0.483、0.376、0.274,P<0.05)。结论:高级别脑胶质瘤DCE-MRI血流动力学参数Ktrans、Kep、Ve水平均高于低级别胶质瘤,且与癌组织分子生物学标记物VEGF、Ki-67表达水平正相关,可用于临床高、低级别脑胶质瘤鉴别。

关键词：脑胶质瘤病理分级动态增强磁共振成像分子生物学标记物

Evidences and implications of vegetation damage from ceramic industrial emission on a rural site in the Pearl River Delta of China

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Journal of Forestry Research 2006年第1期17卷 7-12页

作者： WEN Da-zhi KUANG Yuan wen liU Shi-zhong ZHANG De-qiang LU Yao-dong li jian-li Institute of Ecology South China Botanical Garden. the Chinese Academy of Sciences Guangzhou 510650 P. R. China Foshan Forestry Research Institute Guangdong 528222 P. R. China Forestry Extension Station of Nanhai District Foshan Guangdong 528222 P. R. China

社区结构特征和植被损坏度我们 reinvestigated 并且在村庄附近在一个森林里分析了，它是长期的暴露了到周围的大气污染应力，在植被上从集中的陶器的工业学习在空中的污染物质排出物的影响。现场甸在多山的土地上在一个 semi-naturalse... 详细信息

社区结构特征和植被损坏度我们 reinvestigated 并且在村庄附近在一个森林里分析了，它是长期的暴露了到周围的大气污染应力，在植被上从集中的陶器的工业学习在空中的污染物质排出物的影响。现场甸在多山的土地上在一个 semi-naturalsecondary 森林里被执行，广东省的 Nanhai 区域，为在有 10 X 的全部的区域的十 quadrates 的树层( 10 m x 10 m )，并且为在有 4 X ( 5 mx5 m )的全部的区域的八 subquadrates 的灌木和植物层。结果证明异国情调的桉树类使突出 and 桉树类 urophylla 在社区上被统治，由本国的树种类， Scheffleraoctophylla 和 Bambusa gibba 列在后面与 26.75， 17.08， 16.27 和 11.50 的重要性价值(I_v ) ，分别地。在所有树种类之中，桉树类使突出 and Pinus massoniana 最严重地与将近百分之百损坏的率被损坏。然而， Bambusa gibba 和 Dalbergia balansae 与 85.1%-68.3% 的损坏的率被伤害桉树类 urophylla， Celtis sinensis， Heliciacochinchinensis， Cinnamomum burmanni 和 Vitex 否定松开揭示中等损害(45%-57.5%) 。Mostof 包括 Schefflera octophylla 的另外的土生土长的种类，荚莲属植物 odoratissimum， Desmoschinensis，少些显示出的等等在污染压力下面伤害了症状。与在树层的种类相比，下层林丛的损坏大部分是更少。这些结果建议注意和担心应该在那些上被给予自从 1970-1980s，曾经是的介绍桉树类种类广泛地在华南的降级的多山的陆地为森林恢复使用了，由于他们的快成长方面。结果也由在类似的弄脏的地点为降级的区域的恢复作为目标植物开发本国的种类表明了潜力和观点，它可以提供科学的底让科学家学习并且理解有污染应力的本国的种类和基于过程的相互作用的功能的方面。

关键词：陶瓷工业空气喷射植被珍珠河大气污染

Positive Solutions of Four-order Dierence Equations with Two Point Boundary Value Problems

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湘潭师范学院学报（自然科学版） 2006年第3期28卷 5-9页

作者： CHEN Yu - wen li jian- li Department of Computation Science Huaiyin Institute of Technology Huaian 223001 China Department of Mathematics Hunan Normal University Changsha 410081 China

In this paper,by using the Krasnoselskii xed point theorem,we prove the existence one or multiple of positive solutions of fourth-ordernonlinear dierence equations with two point boundary value problem.

关键词：两点边值问题不动点定理正解四阶微分方程

Effect of ferromanganese additions on non-metallic inclusion characteristics in TRIP steel

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Journal of Iron and Steel Research(International) 2022年第9期29卷 1464-1473页

作者： Wei-sheng Wang Hang-yu Zhu Ming-ming Song jian-li li Zheng-liang Xue The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The inclusion characteristics in extra low-carbon ferromanganese(ELC-FeMn),low-carbon ferromanganese(LC-FeMn),mid-carbon ferromanganese(MC-FeMn),and high-carbon ferromanganese(HC-FeMn)were evaluated by scanning electron microscopy coupled with energy dispersive spectroscopy.The effect of FeMn alloys on the cleanliness of transformation-induced plasticity(TRIP)steel was studied based on laboratory-scale experiments and thermodynamic calculations.The results show that the main inclusions in ELC-FeMn are MnO-MnS and MnS,and the dominant inclusions in LC-FeMn and MC-FeMn are MnO,MnO-SiO_(2),and MnO-SiO_(2)-MnS.The inclusions in HC-FeMn are diversified.Besides MnO-SiO_(2)inclusion,a certain number of Al-,Si-,and Ti-containing inclusions and enrichment phases of Pb,Sn,and P are observed in HC-FeMn.Before FeMn alloy addition,the main inclusion in steel is Al2O.After alloying with the four different grades of FeMn alloy,the main inclusions in TRIP steel are Al_(2)O_(3),AIN,MnS,AlO3-AIN,AINMnS,and Al_(2)O_(3)-MnS.The MnO and SiO_(2)inclusions from FeMn alloys are not detected in TRIP steel.

关键词： Non-metallic inclusion Ferromanganese TRIP steel.Cleanliness FeMn alloy High Al steel

Exploring changes of precipitation extremes under climate change through global variable-resolution modeling

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Science Bulletin 2024年第2期69卷 237-247页

作者： Wei Sun jian li Rucong Yu Nina li Yi Zhang State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China Department of Atmospheric Science Yunnan UniversityKunming 650091China National Meteorological Center China Meteorological AdministrationBeijing 100081China 2035 Future Laboratory PIESAT Information Technology Co.Ltd.Beijing 100105China

Understanding the responses of precipitation extremes to global climate change remains limited owing to their poor representations in models and complicated interactions with multi-scale systems.Here we take the record-breaking precipitation over China in 2021 as an example,and study its changes under three different climate scenarios through a developed pseudo-global-warming(PGW)experimental framework with 60-3 km variable-resolution global ensemble modeling.Compared to the present climate,the precipitation extreme under a warmer(cooler)climate increased(decreased)in intensity,coverage,and total amount at a range of 24.3%-37.8%(18.7%-56.1%).With the help of the proposed PGW experimental framework,we further reveal the impacts of the multi-scale system interactions in climate change on the precipitation extreme.Under the warmer climate,large-scale water vapor transport converged from double typhoons and the subtropical high marched into central China,enhancing the convective energy and instability on the leading edge of the transport belt.As a result,the mesoscale convective system(Mcs)that directly contributed to the precipitation extreme became stronger than that in the present climate.On the contrary,the cooler climate displayed opposite changing characteristics relative to the warmer climate,ranging from the large-scale systems to local environments and to the Mcs.In summary,our study provides a promising approach to scientifically assess the response of precipitation extremes to climate change,making it feasible to perform ensemble simulations while investigating the multi-scale system interactions over the globe.

关键词： Precipitation extreme Climate change Pseudo-global-warming experiment Variable-resolution modeling Multi-scale system interaction