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Synergistic extraction of rare earth elements and alumina from coal fly ash by potassium pyrosulfate

Journal of Rare Earths 2024年第4期42卷 749-758页

作者： Jingjing Zou Yiping Sun Chunbin Guo Daye Chen Yonghong Song yongfeng wu Zhaotianhui Li Department of Environment Science and Engineering Liaoning Technical UniversityFuxin23000China Department of Materials Science and Engineering Liaoning Technical UniversityFuxin123000 China Technology Research and Development Department Chinese Institute of Coal ScienceBeijing100013China Shenhua Zhungeer Energy and Resource Comprehensive Development Co. Ltd.Erdos10300China Liaoning Yingguan High-tech Ceramic Co. Ltd.Jinzhou121213China

Although coal fly ash(CFA)contains a high content of rare earth elements(REEs),the related extraction methods have limitations because of their low efficiencies,high levels of energy consumption,and other drawbacks.To address these problems,in this study,we examined the coextraction of REEs and Al_(2)O_(3)from two types of Al_(2)O_(3)-rich CFA,pulverized CFA(PCFA)and circulating fluidized bed fly ash(CFBFA)using low-temperature calcination in the presence of K_(2)S_(2)O_(7).The total REEs,heavy REEs(HREEs),and light REEs(LREEs)extraction efficiencies were determined using different K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratios and calcination temperatures and correlated with the Al_(2)O_(3) extraction efficiency using Pearson correlation coefficient analysis.The REEs are concentrated within CFA particles encapsulated in an aluminosilicate glass phase,and the REEs extraction efficiency is related to the form of Al in CFA.The extraction efficiencies of Al_(2)O_(3) and REEs increase as the K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratio and calcination temperature increase,and the extraction selectivity of the more industrially valuable HREEs from CFBFA is higher.At high K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratios,the extraction of REEs from PCFA is more efficient than that from CFBFA with the regeneration of the highly active Al-O-Si bonds in CFBFA.The Al_(2)O_(3) extraction efficiencies of PCFA as well as CFBFA correlate strongly with the total REEs,HREEs,and LREEs extraction efficiencies.The developed extraction technology has the potential to promote CFA valorization and expand REEs resources,thus mitigating the bottlenecks of REEs procurement.

关键词： Rare earths Alumina Coal fly ash Potassium pyrosulfate Calcination Extraction

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Complete qth-Moment Convergence of Moving Average Process for m-WOD Random Variable

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wuhan University Journal of Natural Sciences 2022年第5期27卷 396-404页

作者： SONG Mingzhu wu yongfeng CHU Ying Department of Mathematics and Computer Science Tongling UniversityTongling 244000AnhuiChina

In this paper,we obtained complete qth-moment convergence of the moving average processes,which is generated by m-WOD moving random variables.The results in this article improve and extend the results of the moving average process.mWOD random variables include WOD,m-NA,m-NOD and mEND random variables,so the results in the paper also promote the corresponding ones in WOD,m-NA,m-NOD,m-END random variables.

关键词： m-WOD random variable moving average processes complete convergence complete qth-moment convergence

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Distribution and sequential extraction of some heavy metals in urban soils of Guiyang City,China

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Chinese Journal Of Geochemistry 2008年第4期27卷 401-406页

作者： wu yongfeng LIU Congqiang TU Chenglong State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Sixty-two soil samples collected from different functional zones of Guiyang were analyzed for total con-centrations and sequential extraction of Cr,Cu,Pb,Zn and Cd by ICP spectrometry. The average total concentrations of Cr,Cu,Pb,Zn and Cd in the soils of Guiyang were 92.9,51.6,44.1,139.3 and 0.28 mg/kg,respectively. The soils have been polluted by Cr,Cu,Pb,Zn and Cd to some extent in comparison with the background values of Guiyang. Significant differences were recognized in the concentrations of Cr,Cu,Pb,Zn and Cd in different functional zones. As for the sequential extraction,Cr,Cu and Zn were present mainly in the residual fraction,and Pb was present mainly in the oxidizable fraction. The reducible fraction of Cd accounts for 47.5%,and the residual fraction is lowest. The mobility and bioavailability of heavy metals follow the order of Cd>Pb>Cu>Cr>Zn.

关键词：贵州土壤重金属物种形成

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Enhanced reversible hydrogen storage properties of wrinkled graphene microflowers confined LiBH_(4) system with high volumetric hydrogen storage capacity

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Materials Reports(Energy) 2024年第1期4卷 79-88页

作者： Zhenglong Li Kaicheng Xian Hao Chen Mingxia Gao Shanqing Qu Meihong wu Yaxiong Yang Wenping Sun Chao Gao yongfeng Liu Xin Zhang Hongge Pan Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an710021PR China State Key Laboratory of Silicon and Advanced Semiconductor Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang ProvinceSchool of Materials Science and EngineeringZhejiang UniversityHangzhou310027PR China Department of Polymer Science and Engineering MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationZhejiang UniversityHangzhou310027PR China

LiBH_(4)with high hydrogen storage density,is regarded as one of the most promising hydrogen storage materials.Nevertheless,it suffers from high dehydrogenation temperature and poor reversibility for practical use.Nanoconfinement is effective in achieving low dehydrogenation temperature and favorable reversibility.Besides,graphene can serve as supporting materials for LiBH_(4)catalysts and also destabilize LiBH_(4)via interfacial reaction.However,graphene has never been used alone as a frame material for nanoconfining LiBH_(4).In this study,graphene microflowers with large pore volumes were prepared and used as nanoconfinement framework material for LiBH_(4),and the nanoconfinement effect of graphene was revealed.After loading 70 wt%of LiBH_(4) and mechanically compressed at 350 MPa,8.0 wt% of H2 can be released within 100 min at 320C,corresponding to the highest volumetric hydrogen storage density of 94.9 g H2 L^(-1)ever reported.Thanks to the nanoconfinement of graphene,the rate-limiting step of dehydrogenation of nanoconfined LiBH_(4) was changed and its apparent activation energy of the dehydrogenation(107.3 kJ mol^(-1))was 42%lower than that of pure LiBH_(4).Moreover,the formation of the intermediate Li_(2)B_(12)H_(12) was effectively inhibited,and the stable nanoconfined structure enhanced the reversibility of LiBH_(4).This work widens the understanding of graphene's nanoconfinement effect and provides new insights for developing high-density hydrogen storage materials.

关键词： Hydrogen storage LiBH_(4) Nanoconfinement Graphene High capacity

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K6型单层球面网壳整体交互耦合屈曲行为

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同济大学学报（自然科学版） 2024年第4期52卷 557-566页

作者：毋凯冬张业成伞冰冰罗永峰河海大学土木与交通学院江苏南京210098 同济大学土木工程学院上海200092

采用有限元数值模拟,基于K6型单层球面网壳的屈曲与后屈曲性态,提出整体屈曲的判别准则,并首次从变形特征角度分析两种整体屈曲模态交互耦合的发生机理及对屈曲承载力的削弱效应。研究结果表明,K6型单层球面网壳的稳定性易受整体交互耦... 详细信息

采用有限元数值模拟,基于K6型单层球面网壳的屈曲与后屈曲性态,提出整体屈曲的判别准则,并首次从变形特征角度分析两种整体屈曲模态交互耦合的发生机理及对屈曲承载力的削弱效应。研究结果表明,K6型单层球面网壳的稳定性易受整体交互耦合屈曲影响,且可导致屈曲极限承载力的显著削弱及不稳定后屈曲;其变形模式从屈曲阶段的最低阶整体屈曲模态主导,演化为初始后屈曲阶段的整体交互耦合屈曲模态主导,及最终的次低阶整体屈曲模态主导,是交互耦合屈曲产生的原因;缺陷幅值也会影响整体交互耦合屈曲对K6型单层球面网壳屈曲极限性能的主导作用。

关键词：空间结构网壳结构有限元模拟耦合屈曲非线性稳定

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A centromere map based on super pan-genome highlights the structure and function of rice centromeres

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Journal of Integrative Plant Biology 2024年第2期66卷 196-207页

作者： Yang Lv Congcong Liu Xiaoxia Li Yueying Wang Huiying He Wenchuang He wu Chen Longbo Yang Xiaofan Dai Xinglan Cao Xiaoman Yu Jiajia Liu Bin Zhang Hua Wei Hong Zhang Hongge Qian Chuanlin Shi Yue Leng Xiangpei Liu Mingliang Guo Xianmeng Wang Zhipeng Zhang Tianyi Wang Bintao Zhang Qiang Xu Yan Cui Qianqian Zhang Qiaoling Yuan Noushin Jahan Jie Ma Xiaoming Zheng yongfeng Zhou Qian Qian Longbiao Guo Lianguang Shang State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhou 310006China Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China Yazhouwan National Laboratory No.8 Huanjin RoadYazhou DistrictSanya City 572024China National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop ScienceChinese Academy of Agricultural SciencesBeijing 100081China

Rice(Oryza sativa)is a significant crop worldwide with a genome shaped by various evolutionary factors.Rice centromeres are crucial for chromosome segregation,and contain some unreported genes.Due to the diverse and complex centromere region,a comprehensive understanding of rice centromere structure and function at the population level is needed.We constructed a high-quality centromere map based on the rice super pangenome consisting of a 251-accession panel comprising both cultivated and wild species of Asian and African rice.We showed that rice centromeres have diverse satellite repeat CentO,which vary across chromosomes and subpopulations,reflecting their distinct evolutionary patterns.We also revealed that long terminal repeats(LTRs),especially young Gypsy-type LTRs,are abundant in the peripheral CentO-enriched regions and drive rice centromere expansion and evolution.Furthermore,high-quality genome assembly and complete telomere-to-telomere(T2T)reference genome enable us to obtain more centromeric genome information despite mapping and cloning of centromere genes being challenging.We investigated the association between structural variations and gene expression in the rice centromere.A centromere gene,OsMAB,which positively regulates rice tiller number,was further confirmed by expression quantitative trait loci,haplotype analysis and clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein9 methods.By revealing the new insights into the evolutionary patterns and biological roles of rice centromeres,our finding will facilitate future research on centromere biology and crop improvement.

关键词： centromere super pan-genome CentoO satellite repeat rice

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中国式现代化蕴含的独特文明观

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中共济南市委党校学报 2024年第2期 17-22页

作者：王永凤吴凤北京交通大学马克思主义学院北京100044

中国式现代化文明观实现了对马克思主义文明观的守正创新、对中华民族传统文明观的转化发展以及对西方资本主义文明观的批判超越。中国式现代化在发展过程中秉持人民至上理念、采取和平发展方式、选择并联式发展道路、坚持文明交流互鉴... 详细信息

中国式现代化文明观实现了对马克思主义文明观的守正创新、对中华民族传统文明观的转化发展以及对西方资本主义文明观的批判超越。中国式现代化在发展过程中秉持人民至上理念、采取和平发展方式、选择并联式发展道路、坚持文明交流互鉴。中国式现代化文明观的独特价值在于其深化了党对文明发展规律的认识,激发了社会主义文明建设的活力;能够切实解决现代化进程中的难题,彰显中国的实践方略和智慧;开辟了全新的现代文明发展道路,引领人类文明新形态的创造。

关键词：中国式现代化文明观理论渊源核心理念独特价值

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血清学标志物甲胎蛋白、PIVKA-Ⅱ和磷脂酰肌醇蛋白聚糖3联合诊断肝癌的meta分析

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浙江大学学报（医学版） 2024年第1期53卷 131-139页

作者：宋红亮王建国张会吴勇锋汪恺王晓波徐骁浙江中医药大学第四临床医学院浙江杭州310053 浙江省肿瘤融合研究与智能医学重点实验室浙江杭州310003

目的:探讨血清生物标志物甲胎蛋白(AFP)、维生素K缺失或拮抗剂Ⅱ诱导的蛋白质(PIVKA-Ⅱ)和磷脂酰肌醇蛋白聚糖3(GPC-3)单独或联合用于肝细胞癌(以下简称肝癌)诊断的价值。方法:检索PubMed、Web of Science、Embase三个数据库,收集2002... 详细信息

目的:探讨血清生物标志物甲胎蛋白(AFP)、维生素K缺失或拮抗剂Ⅱ诱导的蛋白质(PIVKA-Ⅱ)和磷脂酰肌醇蛋白聚糖3(GPC-3)单独或联合用于肝细胞癌(以下简称肝癌)诊断的价值。方法:检索PubMed、Web of Science、Embase三个数据库,收集2002年以来发表的AFP、PIVKA-Ⅱ和GPC-3单独或联合用于诊断肝癌的文献。根据纳入和排除标准筛选文献并提取相关数据。利用诊断准确性研究的质量评价(QUADAS)检查表对纳入的文献进行质量评价,并采用Meta DiSc软件、Review Manager 5.4软件和Stata 15.1软件对AFP、PIVKA-Ⅱ和GPC-3单用和联合使用诊断肝癌的受试者工作特征曲线下面积(AUC)、敏感度、特异度等指标进行数据分析。结果:共纳入32篇文献。Meta分析结果显示,单个标志物用于诊断肝癌时,PIVKA-Ⅱ的AUC值最高,为0.88(95%CI:0.85~0.91),其次是GPC-3和AFP;多个标志物联合用于诊断肝癌的AUC均高于单个标志物,其中PIVKA-Ⅱ联合GPC-3诊断的AUC值最高,为0.90(95%CI:0.87~0.92)。单个标志物用于诊断肝癌时,PIVKA-Ⅱ和GPC-3的敏感度相对较高(分别为0.75和0.76),但GPC-3的特异度不如PIVKA-Ⅱ和AFP(AFP、PIVKA-Ⅱ和GPC-3分别为0.87、0.88和0.81);多个标志物联合用于诊断肝癌的敏感度较单个标志物诊断时有所提高,但特异度无明显提高。单个标志物用于诊断肝癌时,PIVKA-Ⅱ的诊断比值比(DOR)最高,为22(95%CI:13~36),其次是GPC-3和AFP;两个标志物联合用于诊断肝癌的DOR均高于单个标志物,其中AFP联合GPC-3诊断的DOR最高,为25(95%CI:9~67);三个标志物联合用于诊断肝癌时的DOR明显降低,为10(95%CI:7~45)。结论:单个标志物用于肝癌诊断时,PIVKA-Ⅱ的诊断价值更高。两种标志物联合能显著提高肝癌诊断的敏感度,三种标志物联合未能进一步提高诊断价值。结合临床实际,推荐AFP联合PIVKA-Ⅱ用于肝癌的诊断。

关键词：肝细胞癌血清学标志物甲胎蛋白维生素K缺失或拮抗剂Ⅱ诱导的蛋白质磷脂酰肌醇蛋白聚糖3 诊断 meta分析

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Changes and spatial patterns of eco-environment in the farming-pastoral region of northern China

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Journal of Geographical Sciences 2005年第3期15卷 329-336页

作者： JIANG Weiguo LI Jing LI Jiahong CHEN Yunhao wu yongfeng College of Resources Science and Technology Beijing Normal University Beijing 100875China National Remote Sensing Center of China Chinese Ministry of Science andTechnology Beijing 100862 China

This paper firstly selects 10 kinds of indexes to reflect eco-environment background condition and builds the multi-subject spatial database by using ground meteorological data, remote sensing data and DEM. It then discusses in detail the methods about evaluating eco-environment background condition and analyzing eco-environment change. The eco-environment background conditions of 1989 and 1999 are synthetically appraised. Finally, the paper analyzes the spatial distribution, quantitative change, the trend of change, the areas of change and the dynamic spatial pattern of eco-environment. The results are as follows：（1） The eco-environment background condition becomes worse from southeast to northwest in the fanning-pastoral region of northern China. （2） The eco-environment background condition deteriorates from 1989 to 1999. （3） In the adjacent areas of Shanxi-Shaanxi-Inner Mongolia-Gansu-Ningxia, Horqin Sandy Land and its peripheries, and eastern Qinghai orovince, eco-environmental deterioration is very serious.

关键词： fanning-pastoral region eco-environment spatial pattern northern China

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BIM技术在某建筑项目施工管理中的应用

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四川建材 2024年第1期50卷 216-219页

作者：袁明慧武永峰江苏建筑职业技术学院江苏徐州221116

BIM技术作为建筑业产业化和信息化的关键工具,显著促进行业的发展。某建筑项目施工工期紧、场地狭窄、基坑开挖难度大、异形结构复杂,利用BIM技术实现施工管理,在创建三维模型的基础上,完成节点深化、精细化排砖,创建虚拟施工样板;分阶... 详细信息

BIM技术作为建筑业产业化和信息化的关键工具,显著促进行业的发展。某建筑项目施工工期紧、场地狭窄、基坑开挖难度大、异形结构复杂,利用BIM技术实现施工管理,在创建三维模型的基础上,完成节点深化、精细化排砖,创建虚拟施工样板;分阶段三维场地布置,模拟基坑开挖和施工现场交通;5D虚拟建造实现工期控制和各阶段资金把控,强化工程管控,优化效率,提升施工技术和质量,追求施工效果最优。

关键词： BIM 施工管理节点深化虚拟建造

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