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急性A型主动脉夹层患者术后死亡风险的预测模型

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中华胸心血管外科杂志 2024年第2期40卷 72-78页

作者：李沛泉张韶鹏白云鹏陈彤云赵丰姜楠陈庆良天津医科大学研究生院天津300070 天津大学附属胸科医院心血管外科、天津心血管病研究所、天津市重点实验室天津300382

目的采用不同的机器学习算法,构建并筛选预测急性A型主动脉夹层患者术后30天内死亡风险的最佳预测模型。方法纳入2015年至2022年间行手术治疗的急性A型主动脉夹层患者521例,收集其围手术期资料并进行筛选后保留329例。分别通过Lasso回... 详细信息

目的采用不同的机器学习算法,构建并筛选预测急性A型主动脉夹层患者术后30天内死亡风险的最佳预测模型。方法纳入2015年至2022年间行手术治疗的急性A型主动脉夹层患者521例,收集其围手术期资料并进行筛选后保留329例。分别通过Lasso回归和主成分分析确定两组不同的预测变量后,使用逻辑回归和支持向量机、随机森林、梯度提升、超级学习算法建立预测术后30天内死亡风险的预测模型,并使用ROC曲线、敏感度值和特异度值等指标对各个模型进行比较。结果所有模型的ROC曲线下面积(AUC)0.791~0.959,使用Lasso回归确定预测变量,并通过超级学习算法建立的模型预测效果最佳,AUC 0.959。结论在对急性A型主动脉夹层术后30内死亡的预测中,超级学习算法优于其他算法。

关键词：急性A型主动脉夹层机器学习预测模型死亡

Neutron activation analysis (NAA) and geochemical studies of 38 elements in surface sediments from lower reach and estuary of Huanghe (Yellow) River

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Acta Oceanologica Sinica 1990年第2期9卷 227-246页

作者： li peiquan Chih-An Huh Zhihxin Zhang Weizhi Tian Lu Guanshan

Using a neutron activation analysis technique, which involves gamma-spectrometry with a Ge(li) detector coupled to a S40 multichannel analyzer and interfaced to a PDP-11 computer, we determined thirty-eight elements in sediments from the lower reach (downstream from Jinan) and estuary of Huanghe. The results are discussed in this *** inter-elemental correlations, it ts found that a large number of metals (***, Co, ***, Rb, Sc, Ti, Ta, V and Zn) correlate positively with Fe. Ba and Ca correlate positively with Al. Whereas some elements (e. g. , Ti and lanthanides) show no correlation with either Fe or Al. On the other hand, Hf and Zr show a negative correlation with Fe. Elements which tend to be scavenged by Fe and Al colloids or suspended particles are enriched in sediments at the Huanghe Estuary relative to its lower reach. On the other hand, the contents of some elements (e. g. , Zr,Hf,U, Ba, etc. )are higher in sediments from the lower reach of Huanghe than in the estuarine sediments,which may be related to the sorting during deposition of source materials. On the basis of their chemical property and geochemical behavior, the 38 elements we studied are classified into seven groups. (1) weathering-prone elements,group A:K,Rb, Cs and Na; (2) weathering-prone elements, group B:Mg, Ca, Ba and Al; (3) transition elements:Fe, ***, Zn, As, Sb, Mn, Cr, W,Mo,V, Ta and Sc; (4) rare elements:group A (Zr and Hf) and group B (Ti); (5) rare earth elements:the lanthanides; (6) halogens: Cl and Br; amd (7) natural radioactive elements:U and Th. The basis for this classification is discussed and we emphasize that geochemical associations of elements in the natural environment are not necessarily in accord with their chemical properties as dictated by position at the periodic table.

关键词： Yellow and geochemical studies of 38 elements in surface sediments from lower reach and estuary of Huanghe River NAA

GEOCHEMICAL STUDIES OF U, TH, RA, 40K IN SECIMENTS OF THE CHINA SEA AND ADJACENT SEA AREA, AND LOWER REACHES OF SEVERAL CHINESE RIVERS

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Chinese Journal of Oceanology and limnology 1987年第2期5卷 109-117页

作者：李培泉刘志和 Institute of Oceanology Academia Sinica Qingdao Shandong Institute of Medical Science Jinan

Geochemical studies of the U, Th, Ra, and 40K in surface sediments of the China Sea and adjacent sea areas, the lower reaches of the Huanghe and Changjiang Rivers and the estuaries of the Zhujiang and Rongjiang Rivers were carried out with a model 8180-4K multichannel Ge(li)y spectrometer in 1981-1985. The .mean values of U, Ra, Th, 40K are about 2.11 ppm, 7.67×10-13g/g, 11.00 ppm, and 2.33 ppm respectively, in the China Sea, the Okinawa Trough, and the Changjiang and Huanghe River estuaries. The distribution of the four isotopes is uniform in the above *** contents of U and Th in the sediments of the Zhujiang and Rongjiang Rivers and the Fujian coast are 1-4 times higher than those of the above zone and are related to the granite and radioactive ore present in the upper reaches of these rivers or the adjacent *** distributions of U, Th, Ra, and 40K are related to the physico-chemical property, redox state, geological type and grain size of the sediment, and biotic activity.

关键词： Th Ra AND LOWER REACHES OF SEVERAL CHINESE RIVERS GEOCHEMICAL STUDIES OF U K IN SECIMENTS OF THE CHINA SEA AND ADJACENT SEA AREA SEA RA

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淮南矿区水体下采煤的实践与认识

中国煤炭 2001年第4期27卷 30-32,42页

作者：李佩全淮南矿业(集团)公司安徽淮南市232001

结合淮南矿区水体下采煤的实践 ,研究了正常采矿及地质条件下急倾斜、倾斜和缓倾斜煤层导水裂隙带高度发育的规律及计算公式 ,介绍了水体下开采时充分利用粘土类隔水层的防水性能和防水煤岩柱的留设方法。采用这些研究成果 ,淮南和潘谢... 详细信息

结合淮南矿区水体下采煤的实践 ,研究了正常采矿及地质条件下急倾斜、倾斜和缓倾斜煤层导水裂隙带高度发育的规律及计算公式 ,介绍了水体下开采时充分利用粘土类隔水层的防水性能和防水煤岩柱的留设方法。采用这些研究成果 ,淮南和潘谢矿区分别提高了开采上限 ,增加了可利用储量。

关键词：水体下采煤技术途径淮南矿区防水煤岩柱导水裂隙带

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黄河口区域放射性核素的调查

中华放射医学与防护杂志 1989年第4期9卷 262-264页

作者：刘志和李培泉山东省医学科学院，济南

本文报道了黄河三角洲土壤和沉积物中放射性核素 238U. 232Th. 226Ra. 40K. 137Cs的调查结果。结果表明，天然放射性核素的分布比较均匀，沉积物中 137Cs含量随深度的变化，反应出地球表面放射性落下灰年... 详细信息

本文报道了黄河三角洲土壤和沉积物中放射性核素 238U. 232Th. 226Ra. 40K. 137Cs的调查结果。结果表明，天然放射性核素的分布比较均匀，沉积物中 137Cs含量随深度的变化，反应出地球表面放射性落下灰年累积总量的变化规律。毛蛤蜊对放射性核素有选择性吸收，不同海域的毛蛤蜊的吸收系数相同。

关键词：沉积物天然放射性黄河

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu Cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li *** a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： li metal batteries li dendrites Electrolyte additive

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热管余热锅炉在兴澄特钢电炉上的应用

冶金能源 2010年第1期29卷 45-47页

作者：李佩泉江阴兴澄特种钢铁有限公司

简单介绍了兴澄特钢100 t电炉余热回收改造的过程,从换热元件的工作原理上对热管余热锅炉进行了分析,并对其优缺点进行了阐述及总结。

关键词：电炉热管余热锅炉

Leaching kinetics of fluorine during the aluminum removal from spent li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie li Jianxin Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent li-ion battery cathode *** this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent li-ion batteries(liBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery *** mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this *** leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/***,the leaching of F was attributed to the dissolution of liPF6and decomposition of PVDF,and the kinetics associated was described by Avrami *** interaction of Al and F is advantageous to realize the defluoridation to some *** is expected that our investigation will provide theoretical support for the large-scale recycling of spent liBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

SEI/dead li-turning capacity loss for high-performance anode-free solid-state lithium batteries

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Journal of Energy Chemistry 2024年第9期96卷 145-152页

作者： Qianwen Yin Tianyu li Hongzhang Zhang Guiming Zhong Xiaofei Yang Xianfeng li Division of Energy Storage Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Long-Duration and Large-Scale Energy Storage Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Laboratory of Advanced Spectro-Electrochemistry and lithium-Ion Batteries Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Anode-free solid-state lithium metal batteries(AF-SSLBs)have the potential to deliver higher energy density and improved safety beyond lithium-metal ***,the unclear mechanism for the fast capacity decay in AF-SSLBs,either determined by dead li or solid electrolyte interface(SEI),limits the proposal of effective strategies to prolong cycling *** clarify the underlying mechanism,herein,the evolution of SEI and dead li is quantitatively analyzed by a solid-state nuclear magnetic resonance(ss-NMR)technology in a typical liPF6-based polymer *** results show that the initial capacity loss is attributed to the formation of SEI,while the dead li dominates the following capacity loss and the growth rate is 0.141 mA h cm^(−2)cycle−*** reduce the active li loss,the combination of inorganic-rich SEI and self-healing electrostatic shield effect is proposed to improve the reversibility of li deposition/dissolution behavior,which reduces the capacity loss rate for the initial SEI and following dead li generation by 2.3 and 20.1 folds,*** a result,the initial Coulombic efficiency(ICE)and stable CE increase by 15.1%and 15.3%in li-Cu cells,which guides the rational design of high-performance AF-SSLBs.

关键词： Solid-state lithium batteries Solid-state NMR Anode-free SEI Dead li