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基于马尔可夫链的COVID-19流行病患病区域变化趋势预测

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陕西科技大学学报 2025年第1期43卷 211-218页

作者：王鑫王令戈师鹏柔陕西科技大学电子信息与人工智能学院陕西西安710021

在COVID-19疫情环境下,为精准预测不同症状状态的人群人数和区域级别的发展趋势,以SIR传染病模型为基础,基于马尔可夫链预测时空相关的特性,设计了感染人群状态与管控措施相关的K-SIRD传染病预测模型.根据COVID-19疫情人群之间传染性的... 详细信息

在COVID-19疫情环境下,为精准预测不同症状状态的人群人数和区域级别的发展趋势,以SIR传染病模型为基础,基于马尔可夫链预测时空相关的特性,设计了感染人群状态与管控措施相关的K-SIRD传染病预测模型.根据COVID-19疫情人群之间传染性的特征及受距离影响造成有效传染数R e的变化而导致不同的症状状态改变的转移规律,实时精准预测了不同状态的人员人数变化,并根据同一区域人群症状状态分布情况不同,针对不同级别的区域采用不同等级的管控措施.

关键词： K-SIRD模型 COVID-19 马尔可夫链有效繁殖数

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Plastome characteristics and species identification of Chinese medicinal wintergreens(Gaultheria,Ericaceae)

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Plant Diversity 2022年第6期44卷 519-529页

作者： Yan-ling Xu Hao-Hua Shen Xin-Yu du Lu Lu School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products Kunming Medical UniversityKunmingYunnanChina Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnanChina

Wintergreen oil is a folk medicine widely used in foods,pesticides,cosmetics and *** China,nine out of 47 species within Gaultheria(Ericaceae)are traditionally used as Chinese medicinal wintergreens;however,phylogenetic approaches currently used to discriminating these species remain *** this study,we sequenced and characterized plastomes from nine Chinese wintergreen species and identified candidate DNA barcoding regions for *** Gaultheria plastome contained 110 unique genes(76 protein-coding,30 tRNA,and four rRNA genes).duplication of trnfM,rps14,and rpl23 genes were detected,while all plastomes lacked ycf1 and ycf2 *** plastomes shared substantially contracted SSC regions that contained only the ndhF ***,plastomes of Gaultheria leucocarpa *** contained an inversion in the LSC region and an IR expansion to cover the ndhF *** rearrangement events apparently occurred between the Gaultheria plastomes and those from several previously reported families in *** phylogenetic reconstruction using 42 plastomes revealed well-supported relationships within all nine Gaultheria ***,seven mutational hotspot regions were identified as potential DNA barcodes for Chinese medicinal *** study is the first to generate complete plastomes and describe the structural variations of the complicated genus *** addition,our findings provide important resources for identification of Chinese medicinal wintergreens.

关键词： DNA barcodes Gene duplication Plastome Repeat sequences Structural variation

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天然和饱水红砂岩三轴压缩蠕变变形试验研究

三峡大学学报（自然科学版） 2025年第1期47卷 9-15页

作者：刘桃根胡凯李玲王伟湖南工学院土木与建筑工程学院湖南衡阳421002 河海大学岩土工程科学研究所南京210098 江西职业技术大学建筑工程学院江西九江332007

蠕变特性和长期强度是红砂岩地区岩体工程安全评价的关键要素,饱水软化效应对红砂岩蠕变特性和长期强度具有重要影响.采用全自动岩石三轴压缩伺服流变仪,开展天然与饱水红砂岩的三轴压缩试验和三轴压缩蠕变试验.试验结果表明:峰值强度... 详细信息

蠕变特性和长期强度是红砂岩地区岩体工程安全评价的关键要素,饱水软化效应对红砂岩蠕变特性和长期强度具有重要影响.采用全自动岩石三轴压缩伺服流变仪,开展天然与饱水红砂岩的三轴压缩试验和三轴压缩蠕变试验.试验结果表明:峰值强度、弹性模量和蠕变破坏应力因饱水软化效应而降低,围压对其降幅有削弱作用,蠕变破坏应力与峰值强度的比值在0.75~0.98之间;饱水软化效应能增强蠕变瞬时变形,减弱蠕变变形及蠕变应变速率;环向应变比轴向应变更早进入稳态蠕变阶段和加速蠕变阶段;稳态蠕变速率与偏压的变化关系符合指数函数关系;长期强度因饱水软化作用而降低,却因围压增加而增大,长期强度与峰值强度的比值在0.62~0.92之间;裂纹损伤应力与长期强度相差较大,裂纹损伤应力视为长期强度有待进一步考究.

关键词：红砂岩蠕变特性长期强度饱水软化效应裂纹损伤应力

Labdane Diterpenoids from Coleus forskohlii （Willd.） Briq.

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Journal of Integrative Plant Biology 2006年第4期48卷 478-481页

作者： ling-ling Xu ling-Yi Kong Department of Natural Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

in order to investigate the active substances of Coleus forskohlii（Wiiid.） Brlq., a new labdane dlterpenold, 12- hydroxy-8,*** acid, together with two 8,13-epoxylabd-14-ene-11-one dlterpenolds, 6-acetyl-1- deoxyforskolln and 6-acetyl-1,9-dldeoxyforskolln, was Isolated on the basis of various chromatographic technlques and spectroscopic methods.

关键词： 6-acetyl-1-deoxyforskolin 6-acetyl-1 ,9-dideoxyforskolin Coleus forskohlii 12-hydroxy-8,13E-labdadien-15-oic acid labdane diterpenoid.

A Comparison of Corrosion Behavior in Saline Environment: Rare Earth Metals (Y, Nd, Gd, Dy) for Alloying of Biodegradable Magnesium Alloys

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Journal of Materials Science & Technology 2013年第9期29卷 781-787页

作者： Xu Zhao ling-ling Shi Jian Xu Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

Rare earth （RE） metals are widely used as the alloying implants. However, corrosion behavior of pure RE elements in biodegradable magnesium alloys as medical metals not only in physiological media but also in chlorinated saline environment is not well understood. In the present work, the RE metals Y, Nd, Gd and Dy are selected to investigate their corrosion behavior in 0.1 mol/L NaCI solution with immersion and electrochemistry techniques. As indicated, corrosion of the currently investigated RE metals is promoted in the order of Dy, Y, Gd and Nd. In terms of electrochemical response, such a sequence correlates with the increased impedance and the decreased corrosion rate （CR）. These RE metals manifest weak ability for passivation in the native surface. Then, reaction with aqueous solution easily happens through the anodic dissolution and cathodic hydrogen evolution. The corrosion products, RE（OH）3, adhered on the surface of RE metals, do not have an appreciable power to resist the reaction proceeding with corrosive chloride ions. In contrast to pure Mg, the RE metals, including Y, Nd, Gd and Dy, exhibit significantly fragile corrosion resistance in saline media. Therefore, with the curr correlation of corrosion resistance between RE-contain ent findings, it is impossible to reveal a well-defined ng Mg alloy and RE metal itself

关键词： Rare earth Biodegradable metal Magnesium alloy Corrosion behavior

Engineering nanoparticle structure at synergistic Ru-Na interface for integrated CO2 capture and hydrogenation

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Journal of Energy Chemistry 2025年第1期 779-791页

作者： Hanzi Liu ling Cen Xinlin Xie Lei Liu Zhao Sun Zhiqiang Sun Hunan Engineering Research Center of Clean and Low-Carbon Energy Technology School of Energy Science and Engineering Central South University

The development of dual functional material for cyclic CO2capture and hydrogenation is of great significance for converting diluted CO2into valuable fuels,but suffers from kinetic limitation and deactivation of adsorbent and ***,we engineered a series of RuNa/γ-Al2O3materials,varying the size of ruthenium from single atoms to clusters/*** coordination environment and structure sensitivity of ruthenium were quantitatively investigated at atomic *** findings reveal that the reduced Ru nanoparticles,approximately 7.1 nm in diameter with a Ru-Ru coordination number of 5.9,exhibit high methane formation activity and selectivity at 340°*** Ru-Na interfacial sites facilitate CO2migration through a deoxygenation pathway,involving carbonate dissociation,carbonyl formation,and ***-situ experiments and theoretical calculations show that stable carbonyl intermediates on metallic Ru nanoparticles facilitate heterolytic C–O scission and C–H bonding,significantly lowering the energy barrier for activating stored CO2.

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durability and microstructure analysis of the road base material prepared from red mud and flue gas desulfurization fly ash

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International Journal of Minerals,Metallurgy and Materials 2020年第4期27卷 555-568页

作者： Emile Mukiza ling-ling Zhang Xiao-ming Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

The present study aimed to investigate the durability and microstructure evolution of road base materials(RBM)prepared from red mud and flue gas desulfurization fly *** durability testing showed that the strength of RBM with the blast furnace slag addition of 1wt%,3wt%and 5wt%reached 3.81,4.87,and 5.84 MPa after 5 freezing–thawing(F–T)cycles and reached 5.21,5.75,and 6.98 MPa after 20 weting–drying(W–D)cycles,*** results also indicated that hydration products were continuously formed even during W–D and F–T exposures,resulting in an increase of the strength and durability of *** observed increase of macropores(>1μm)after F–T and W–D exposures suggested that the mechanism of RBM deterioration is pore enlargement due to cracks that develop inside their ***,the F–T exposure showed a greater negative effect on the durability of RBM compared to the W–D *** leaching tests showed that sodium and heavy metals were solidified below the minimum requirement,which indicates that these wastes are suitable for use as a natural material replacement in road base construction.

关键词： red mud road base material durability microstructure damage mechanism

Placement of prophylactic pancreatic stents to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis in high-risk patients: A meta-analysis

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World Journal of Gastroenterology 2014年第22期20卷 7040-7048页

作者： Qing-Qing Shi Xiao-Yi Ning ling-ling Zhan Guo-du Tang Xiao-Ping Lv Department of Gastro-entero-lo-gy the First Affiliated Ho-spital o-f Guangxi Medical University Department o-f Hemato-lo-gy the First Affiliated Ho-spital o-f Guangxi Medical University Department o-f Clinical Experimental Medicine the First Affiliated Ho-spital o-f Guangxi Medical University

AIM: To assess the effectiveness of pancreatic stents for preventing pancreatitis in high-risk patients after endoscopic retrograde cholangiopancreatography (ERCP).

关键词： Pancreatic stent Endoscopic retrograde cholangiopancreatography Pancreatitis Hyperamylasemia Meta-analysis

Some Results on Cohomology of Twisted Smash Coproduct

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Acta Mathematica Sinica,English Series 2022年第8期38卷 1484-1492页

作者： ling JIA Department of Mathematics and Statistics Ludong UniversityYantai 264025P.R.China

With the main motivation to present some alternatives to the cosemisimplicity of twisted Smash coproduct,this paper first gives some basic constructions which make sense to consider the derived functors of some left exact functors from the category of comodules to vector ***,the Hochschild–Serre spectral sequence for twisted Smash coproduct coalgebras is obtained,which extends some results on homological properties given in the category of comodules over Smash coproduct in the literature.

关键词： Twisted Smash coproduct bicomodule coalgebra Hopf algebra spectral sequence