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Journal of Environmental Sciences 2015年第3期27卷 1-10页

作者： lixia zhou Dunxue Zhu Shujuan Zhang Bingcai Pan State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University

Understanding the aggregation and deposition behavior of carbon nanotubes （CNTs） is of great significance in terms of their fate and transport in the environment. Attachment efficiency is a widely used index for well-dispersed CNT solutions. However, in natural waters, CNTs are usually heterogeneous in particle size. The attachment efficiency method is not applicable to such systems. Describing the dispersion stability of CNTs in natural aquatic systems is still a challenge. In this work, a settling curve modeling （SCM） method was developed for the description of the aggregation and deposition behavior of CNTs in aqueous solutions. The effects of water chemistry （natural organic matter, pH, and ionic strength） on the aggregation and deposition behavior of pristine and surface-functionalized multi-walled carbon nanotubes （MWCNTs） were systematically studied to evaluate the reliability of the SCM method. The results showed that, as compared to particle size and optical density, the centrifugal sedimentation rate constant （ks） from the settling curve profile is a practical, useful and reliable index for the description of heterogeneous CNT suspensions. The SCM method was successfully applied to MWCNT in three natural waters. The constituents in water, especially organic matter, determine the dispersion stability of MWCNTs in natural water bodies.

关键词： Settling curveCarbon nanotubesHeterogeneousCentrifugal sedimentationrate constant

Translation of the long-term fundamental studies on viral DNA packaging motors into nanotechnology and nanomedicine

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Science China(Life Sciences) 2020年第8期63卷 1103-1129页

作者： Chenxi Liang Tao Weitao lixia zhou Peixuan Guo Center for RNA Nanobiotechnology and Nanomedicine College of PharmacyCollege of MedicineDorothy M.Davis Heart and Lung Research Instituteand Comprehensive Cancer Center.The Ohio State UniversityColumbusOhio 43210USA Biology Department College of Science and MathematicsSouthwest Baptist UniversityBolivarMissouri 65613USA

Many years of fundamental studies on viral genome packaging motors have led to fruitful applications.The double-stranded DNA(dsDNA)viruses package their genomes into preformed protein shells via nanomotors including several elegant and meticulous coaxial modules.The motor is geared by the hexameric RNA ring.An open washer displayed as hexametric string of phi29 motor ATPase has been reported.The open washer linked into a filament as a queue with left-handed chirality along the dsDNA chain.It was found that a free 5′-and 3′-dsDNA end is not required for one gp16 dimer and four monomers to assemble into the hexametric washer on dsDNA.The above studies have inspired several applications in nanotechnology and nanomedicine.These applications include:(i)studies on the precision motor channels have led to their application in the single pore sensing;(ii)investigations into the hand-in-hand integration of the hexametric pRNA ring have resulted in the emergence of the new field of RNA nanotechnology;and(iii)the studies on the motor stoichiometry of homologous multi-subunits that subsequently have inspired the discovery of new methods in highly potent drug development.This review focuses on the structure and function of the viral DNA packaging motors and describes how fundamental studies inspired various applications.Given these advantages,more nanotechnological and biomedical applications using bacteriophage motor components are expected.

关键词： nanopores packaging motor phi29 pRNA single pore sensing chemical detection peptide differentiation and sensing nanotechnology nanobiotechnology

基于GF-5高光谱数据的昆嵛山区域森林胁迫研究

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森林工程 2024年第1期40卷 55-63页

作者：黄宝华周利霞武娟山东交通学院交通土建工程学院济南250357 山东省数据开放创新应用实验室济南250357 山东星屹时空信息科技有限公司山东烟台264003 烟台市城市规划展示馆山东烟台213167 北京九五益品科技信息有限公司北京101100

为更好地分析森林植被胁迫的生理过程,建立有效的森林监测系统,使用GF-5号高光谱数据对昆嵛山区域植被应力进行遥感健康度估测,GF-5号高光谱数据能够使非破坏性监测叶绿素、类胡萝卜素和花青素含量等叶片色素等重要指标反映植被健康成... 详细信息

为更好地分析森林植被胁迫的生理过程,建立有效的森林监测系统,使用GF-5号高光谱数据对昆嵛山区域植被应力进行遥感健康度估测,GF-5号高光谱数据能够使非破坏性监测叶绿素、类胡萝卜素和花青素含量等叶片色素等重要指标反映植被健康成为可能,适用于当前研究区域的动态健康监测系统。结果显示,混交林健康度均值最高,其次为落叶阔叶林,常绿针叶林和落叶针叶林健康度均值相当;阳坡森林健康度均值最高,其次为半阴坡与半阳坡的森林健康度均值相当,阴坡森林健康度最低;植被健康度与土壤类型呈现一定相关性,与砂土呈现正相关,与粉砂土、黏土呈现负相关关系。研究表明使用与植被冠层中不同类型与胁迫有关的遥感指数来定量表示植被特殊状态、生物物理和生物化学特性,使森林资源的调查监测和管理得以实现。

关键词： GF-5高光谱昆嵛山森林健康度胁迫植被指数

基于VMD-SAST的电能质量扰动分类识别方法

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中国电力 2024年第2期57卷 34-40页

作者：张博智张茹焦东翔王龙宇周一凡周丽霞国网冀北电力有限公司计量中心北京100032

新能源大规模并网以及电力电子设备广泛应用引起的复杂电能质量扰动(power quality disturbances,PQDs)会威胁电力系统的安全稳定运行。针对复杂PQDs难以精准检测识别的问题,提出了一种基于变分模态分解(variational mode decomposition... 详细信息

新能源大规模并网以及电力电子设备广泛应用引起的复杂电能质量扰动(power quality disturbances,PQDs)会威胁电力系统的安全稳定运行。针对复杂PQDs难以精准检测识别的问题,提出了一种基于变分模态分解(variational mode decomposition,VMD)与同步压缩自适应S变换(synchrosqueezing adaptive S-transform,SAST)的PQDs检测识别方法。首先,使用VMD将PQDs信号分解为多个模态分量,每个分量只保留局部扰动特征,降低PQDs信号的复杂度;其次,提取一种SAST时频分析方法,改善时频分辨率,集中频谱中的能量分布,提高对PQDs信号的检测精度;最后,基于VMD-SAST提取扰动特征,利用3种不同算法实现对PQDs信号的分类识别。通过仿真分析表明:所提出的方法具有较高的PQDs分类识别精度、较高的适用性和较强的抗噪声能力。

关键词：电能质量扰动变分模态分解特征提取机器学习

曲唑酮联合文拉法辛治疗重度抑郁症的临床疗效

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国际精神病学杂志 2024年第1期51卷 117-119页

作者：王学刚周莉霞山东省聊城市第四人民医院药学部聊城252000

目的探讨曲唑酮联合文拉法辛治疗重度抑郁症的临床疗效。方法选择我院2020年2月~2022年8月共94例重度抑郁症患者为观察对象,采用数字表随机法分为两组,对照组、观察组各47例。对照组采用文拉法辛治疗,观察组采用曲唑酮联合文拉法辛治疗... 详细信息

目的探讨曲唑酮联合文拉法辛治疗重度抑郁症的临床疗效。方法选择我院2020年2月~2022年8月共94例重度抑郁症患者为观察对象,采用数字表随机法分为两组,对照组、观察组各47例。对照组采用文拉法辛治疗,观察组采用曲唑酮联合文拉法辛治疗,均治疗3个月。比较治疗前后汉密尔顿抑郁量表17项(Hamilton depression rating scale-17,HAMD-17)、汉密尔顿焦虑量表(Hamilton anxiety scale,HAMA),检测治疗前后多巴胺(Dopamine,DA)、5-羟色胺(5-hydroxytryptamine,5-HT),比较治疗期间不良反应发生情况。结果两组治疗后HAMD-17、HAMA两项评分均显著降低,且治疗后观察组两项评分显著低于对照组(P0.05)。结论曲唑酮联合文拉法辛治疗重度抑郁症能够降低焦虑抑郁情绪,提升血清DA、5-HT水平,具有疗效促进作用,且未显著增加不良反应发生率。

关键词：曲唑酮文拉法辛重度抑郁症多巴胺 5-羟色胺

致密油的CO_(2^(-))水注入驱替模型的仿真实验设计

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实验技术与管理 2024年第2期41卷 156-161页

作者：周丽霞刘雨琪罗亚凌赵承恩王磊中国石油大学(华东)理学院山东青岛266580

该文设计了CO_(2^(-))水注入驱替致密油的仿真实验,引入分子动力学模拟方法,模拟了水驱、CO_(2)驱和CO_(2^(-))WAG驱替纳米孔道内致密油的微观动力学过程,研究了驱替过程中的气、水、油的流动行为、所受阻力及各组分之间的微观相互作用... 详细信息

该文设计了CO_(2^(-))水注入驱替致密油的仿真实验,引入分子动力学模拟方法,模拟了水驱、CO_(2)驱和CO_(2^(-))WAG驱替纳米孔道内致密油的微观动力学过程,研究了驱替过程中的气、水、油的流动行为、所受阻力及各组分之间的微观相互作用,分析了三种驱替方法的驱替效率、驱替速率和临界驱动压强。教学实践证明,学生通过本实验深刻理解了油气田开发的不同驱替方式的微观过程以及不同分子之间的相互作用对驱替过程的影响,掌握了研究油气田开发的分子动力学模拟方法,为进一步开展相关创新研究打下了良好的基础。

关键词：分子动力学 CO_(2^(-))WAG驱临界驱动压强油气田开发

Interactive effects of understory removal and fertilization on soil respiration in subtropical Eucalyptus plantations

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Journal of Plant Ecology 2015年第3期8卷 284-290页

作者： Songze Wan Chenlu Zhang Yuanqi Chen Jie Zhao Xiaolin Zhu Jianping Wu lixia zhou Yongbiao Lin Zhanfeng Liu Shenglei Fu Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of ScienceXingke Road No.723Tianhe DistrictGuangzhou 510650China Graduate University of the Chinese Academy of Sciences Yuquan Road No.19Shijingshan DistrictBeijing 100049China Key laboratory of Plant Stress Biology College of Life ScienceHenan UniversityMinglun StreetJinming RoadKaifeng CityHenan 475004China Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesYuandaer Road No.644Furong DistrictChangsha 410125China Institute of Ecology&Environmental Science Nanchang Institute of TechnologyTianxiang Road NO.289Gaoxin DistrictNanchang 330099China

Aims It has been well recognized that understory vegetation plays an important role in driving forest ecosystem processes and functioning.In subtropical plantation forests,understory removal and fertiliza-tion have been widely applied;however,our understanding on how understory removal affects soil respiration and how the process is regulated by fertilization is limited.Here,we conducted an under-story removal experiment combined with fertilization to evaluate the effects of the two forest management practices and their inter-actions on soil respiration in subtropical forest in southern China.Methods The study was conducted in a split-plot design with fertilization as the whole-plot factor,understory removal as the subplot factor and block as the random factor in subtropical Eucalyptus plantations.In total,there were four treatments:control with unfertilized and intact understory(CK),understory removal but without fertilization(UR),with fertilization but without understory removal(FT)and with fertilization+understory removal(FT+UR).Eucalyptus above-and belowground biomass increment,fine root biomass,soil tempera-ture,soil moisture and soil respiration were measured in the present study.understory respiration(Ru)was quantified in different ways:Ru=RCK−Ru or Ru=RFT−R(FT+u);fertilization increased soil respiration(RFI)was also quantified in different ways:RFI=RFT−RCK or RFI=R(FT+u)−Ru.Important Findingsover a 2-year experiment,our data indicate that understory removal significantly decreased soil respiration,while fertilization increased soil respiration.understory removal decreased soil respiration by 28.8%under fertilization,but only 15.2%without fertilization.Fertilization significantly increased soil respiration by 23.6%with the presence of understory vegetation,and only increased by 3.7%when understory was removed,indicating that fertilization increased soil respiration mainly by increasing the contribution of the understory.our study advances our understanding of the interactive effects of understory managemen

关键词： understory removal fertilization interactive effects soil respiration subtropical plantation

孕中晚期胎儿海马折叠角变化的产前MRI研究

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磁共振成像 2024年第5期15卷 24-27,101页

作者：孙悦曹一民伊泽茜孟卫新周立霞河北医科大学第二医院影像科石家庄050051

目的应用产前MRI研究孕中晚期胎儿海马折叠角(hippocampal infolding angle,HIA)的变化规律。材料与方法回顾性分析在河北医科大学第二医院2018年1月至2021年12月行产前MRI检查的孕中晚期正常胎儿影像学资料。于胎儿颅脑MRI的稳态采集... 详细信息

目的应用产前MRI研究孕中晚期胎儿海马折叠角(hippocampal infolding angle,HIA)的变化规律。材料与方法回顾性分析在河北医科大学第二医院2018年1月至2021年12月行产前MRI检查的孕中晚期正常胎儿影像学资料。于胎儿颅脑MRI的稳态采集快速成像(fast imaging employing steady state acquisition,FIESTA)序列冠状切面测量HIA,统计分析中晚孕期胎儿HIA的正常值范围,探讨其与孕龄变化的相关性以及临床应用价值。结果共有139例孕中晚期胎儿纳入研究,孕周20~38(29.17±3.90)周,男胎∶女胎=105∶34。按孕龄分为6组,分析得到胎儿海马折叠角的置信区间。随着孕龄增加,左右两侧HIA均呈线性增大(R^(2)=0.803、0.836,P均<0.001),且右侧HIA大于左侧,但未发现左右两侧存在性别间差异(P=0.898)。结论产前MRI发现孕中晚期胎儿HIA的变化具有一定的规律,可为宫内或生后与海马结构异常相关的疾病提供影像学诊断依据。

关键词：胎儿海马折叠角磁共振成像发育海马结构

急性间歇性卟啉病伴可逆性后部脑病综合征MRI表现

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中国医学影像技术 2024年第2期40卷 309-311页

作者：伊泽茜许敬博曹一民李晓童卜静英周立霞河北医科大学第二医院医学影像科河北石家庄050000

急性间歇性卟啉病(acute intermittent porphyria,AIP)为罕见常染色体显性遗传病,为羟甲基胆素合酶(recombinant hydroxymethylbilane synthase,HMBS)基因突变导致卟胆原脱氨酶(porphobilinogen deaminase,PBGD)活性缺乏所致。PBGD失活致前体物质如胆色素原(porphobilinogen,PBG)和5-氨基乙酰丙酸(5-aminolevulinic acid,5-ALA)体内蓄积,其毒性可影响多个系统^([1]);累及神经系统时,可出现中枢神经、周围神经和自主神经病变。

关键词：卟啉病,急性间歇性后部白质脑病综合征磁共振成像

基于PS-InSAR的建筑及道路动态沉降安全监测

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山东交通学院学报 2024年第2期32卷 53-59页

作者：黄宝华周利霞孔祥侨山东交通学院交通土建工程学院山东济南250357 山东省数据开放创新应用实验室山东济南250357 山东星屹时空信息科技有限公司山东烟台264003 烟台市城市规划展示馆山东烟台213167 鲁东大学资源与环境工程学院山东烟台264025

为研究建筑及道路的动态沉降,采用覆盖威海市环翠区的20景哨兵(Sentinel-1)干涉雷达测量(interferometric synthetic aperture radar,InSAR)数据,采用时间序列永久散射体合成孔径雷达干涉测量(persistent scatterer InSAR,PS-InSAR)技术提取该区域地表不同构筑物沉降点,对环翠区地表建筑物和道路沉降进行动态监测。结果表明:环翠区建筑物高度与沉降正相关;铁路和公路的沉降由北向南依次减小,在山区等人为干扰少、地质条件较好的地区,基本不发生沉降;威海市环翠区年沉降量大于10 mm的点主要分布在冲积-海积物等堆积的北部地区,并集中在码头、建筑区等人工工程地区。北部地区沉降量大的主要原因是环翠区地层较松散,含水量较高,易发生沉降;该地区人工工程相对较多,对地下土体施加压力,导致土层沉降。分析InSAR数据能较好地监测大范围地表沉降情况,为地表沉降治理和决策提供支持。

关键词： InSAR 动态地表沉降 PS-InSAR 建筑物高度