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迁移条件下磷污染红土的宏微观特性研究

工程地质学报 2016年第3期24卷 352-362页

作者：杨小宝黄英昆明理工大学昆明650500 楚雄欣源水利电力勘察设计有限责任公司楚雄675000

以云南红土为研究对象,以六偏磷酸钠为污染源,通过磷污染红土的土柱迁移试验,探讨了土柱不同位置深度磷污染红土的宏微观特性。试验结果表明:随着土柱位置深度的增加,磷污染红土的相对质量、黏粒含量减小,液限、塑限和塑性指数中上部存... 详细信息

以云南红土为研究对象,以六偏磷酸钠为污染源,通过磷污染红土的土柱迁移试验,探讨了土柱不同位置深度磷污染红土的宏微观特性。试验结果表明:随着土柱位置深度的增加,磷污染红土的相对质量、黏粒含量减小,液限、塑限和塑性指数中上部存在最小值;新生成不稳定的β-钠铁矿,红土中磷的含量在中上部出现最大值,土柱表层氧化亚铁的含量最大;其微结构图像由上部致密的鳞片状单元向中部松散的凝块状进而向下部紧密的蜂凝状单元变化,对应孔隙比在中上部存在最大值;浸泡液的铁铝离子浓度随迁移时间延长而增大,渗流液中存在痕量的铁铝离子。磷与红土的作用机理可以从磷土间所存在的水解、吸附络合、还原氧化、成盐等作用过程来解释。其综合作用的结果改变了磷污染红土的宏微观特性。

关键词：磷污染红土理化特性微结构特性作用机理

Multi-field Coupled Inverse Hall–Petch Relations for Ferroelectric Nanocrystals

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Acta Mechanica Solida Sinica 2024年第1期37卷 139-147页

作者： Xiaodong Zhang Wei Yan Xuhui Lou Yujun Chen Zhihong Zhou Qingyuan Wang Lianhua Ma xiaobao Tian Non-Destructive Testing Laboratory School of Quality and Technical SupervisionHebei UniversityBaoding 071002China AVIC Huiyang Aviation Propeller Co. LtdBaoding 071051China Department of Mechanics and Engineering Sichuan UniversityChengdu 610065China Yibin Institute of Industrial Technology Sichuan University Yibin ParkYibin 644000China Research Institute of Interdisciplinary Sciences(RISE) Dongguan University of TechnologyDongguan 523808China School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

Tailoring grain size can improve the strength of polycrystals by regulating the proportion of grains to grain boundaries and the interaction *** the grain size decreases to the nanoscale,the deformation mechanism in polycrystals shifts from being primarily mediated by dislocations to deformation occurring within the grains and grain ***,the mechanism responsible for fine-grain strengthening in ferroelectric materials remains unclear,primarily due to the complex multi-field coupling effect arising from spontaneous *** molecular dynamics simulations,we investigate the strengthening mechanism of barium titanate(BaTiO3),with extremely fine-grain *** material exhibits an inverse Hall–Petch relationship between grain size and strength,rooting in the inhomogeneous concentration of atomic strain and grain ***,we present a theoretical model to predict the transition from the inverse Hall–Petch stage to the Hall–Petch stage based on strength variations with size,which aligns well with the simulation *** has been found that the piezoelectric properties of the BaTiO3 are affected by polarization domain switching at various grain *** study enhances our understanding of the atomic-scale mechanisms that contribute to the performance evolution of fine-grain nano-ferroelectric *** also provides valuable insights into the design of extremely small-scale ferroelectric components.

关键词： Ferroelectrics Multi-field coupling Molecular dynamics Fine-grain reinforcement Inverse Hall-Petch effect

The Impact of the Number of Lanes on Highway Capacity

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The Impact of the Number of Lanes on Highway Capacity

2005全国博士生学术论坛（交通运输工程学科）

作者： yang xiaobao , Zhang Ning School of Economic and Management, Beihang University, Beijing 100083)

＜正＞ This paper attempts to investigate the impact of the number of lanes on highway capacity. Methodologically, we employ the variance analysis of single factor and t - test for modeling the effect of the number of lanes on capacity. The findings show that average capacity per lane decreases with increasing number of lanes on uninterrupted highway sections. The analysis is based on an extensive field survey of traffic flow in Beijing. The implication of the marginal decrease of lane capacity requires that the manuals of highway capacity should be revised for the better plan and design of road network.

关键词： highway capacity the number of lanes impact marginal decrease

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双交替极横向磁通直线电机的基础研究

中国电机工程学报 2019年第7期39卷 1900-1908页

作者：罗俊寇宝泉杨小宝张赫张鲁哈尔滨工业大学电气工程及自动化学院黑龙江省哈尔滨市150001

提出一种新型双交替极横向磁通直线电机。该结构集成了两种交替极横向磁通电机拓扑,位于初级和次级的永磁体产生的磁通以相同的方向与绕组相交链,通过共用部分铁心和绕组,充分利用了电机内部空间,提高了材料利用率,增大了电机推力密度... 详细信息

提出一种新型双交替极横向磁通直线电机。该结构集成了两种交替极横向磁通电机拓扑,位于初级和次级的永磁体产生的磁通以相同的方向与绕组相交链,通过共用部分铁心和绕组,充分利用了电机内部空间,提高了材料利用率,增大了电机推力密度。通过分析电机内磁场分布,建立电机磁网络拓扑,并计算绕组磁链,推导电机电磁力表达式。通过有限元对理论分析进行验证,得到电机磁链、反电势及电磁推力分布波形。研制一台实验样机,测量样机的反电势,验证新结构电机的原理与性能。

关键词：横向磁通直线电机交替极等效磁网络法

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碲纳米结构电子性质的第一性原理研究

材料导报 2014年第20期28卷 146-149页

作者：谭艳枚杨小宝华南理工大学理学院广州510640

采用密度泛函理论计算了碲纳米线和碲纳米带的电荷分布,并且研究了碲纳米带上的氢原子(H)、氟原子(F)和水分子(H2O)吸附。研究发现,六边形纳米线的价带顶(Valence band maximum)和导带底(Conduction band minimum)分布具有三重轴对称性... 详细信息

采用密度泛函理论计算了碲纳米线和碲纳米带的电荷分布,并且研究了碲纳米带上的氢原子(H)、氟原子(F)和水分子(H2O)吸附。研究发现,六边形纳米线的价带顶(Valence band maximum)和导带底(Conduction band minimum)分布具有三重轴对称性,而碲纳米带的VBM和CBM对应的电荷分布和自身的结构对称性相符。由于碲纳米带结构自身的非对称性,导致内部电荷发生转移,使VBM和CBM分别分布在纳米带的两端。碲纳米带上吸附H和F原子时,碲纳米带呈现p型特性;吸附H2O分子时,碲纳米带与H2O分子呈弱相互作用,不改变碲纳米带的电子性质。

关键词：碲纳米线碲纳米带电荷分离原子和分子吸附

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磷污染红土的受力特性研究

水文地质工程地质 2016年第1期43卷 143-148,170页

作者：杨小宝黄英潘泰昆明理工大学电力工程学院云南昆明650500

以云南红土为研究对象,以六偏磷酸钠为污染源,考虑六偏磷酸钠的浓度和干密度对红土力学特性的影响,采用击实、直剪、压缩、渗透等试验方法,研究了磷污染红土的受力特性变化。试验结果表明:随磷浓度增加,磷污染红土的最大干密度增大,最... 详细信息

以云南红土为研究对象,以六偏磷酸钠为污染源,考虑六偏磷酸钠的浓度和干密度对红土力学特性的影响,采用击实、直剪、压缩、渗透等试验方法,研究了磷污染红土的受力特性变化。试验结果表明:随磷浓度增加,磷污染红土的最大干密度增大,最优含水率减小,存在最优浸润时间;磷污染红土的黏聚力降低,内摩擦角减小,压缩性增大,渗透性降低;对受力前后的磷污染红土进行微结构图像拍摄,进而证实了磷污染红土力学性能变化是磷污染红土微结构弱化所致;磷污染红土力学特性变化可从磷对红土力学特性的影响来解释。该研究成果可为工程实践中磷污染劣化红土力学特性提供理论参考。

关键词：磷污染红土受力特性微结构特性磷土作用

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交通拥堵持续时间的非参数生存分析

北京交通大学学报 2013年第2期37卷 134-137页

作者：杨小宝周映雪北京交通大学城市交通复杂系统理论与技术教育部重点实验室北京100044

采用生存分析的非参数方法,建立基于风险的交通拥堵持续时间模型,根据北京市三环快速路的交通流数据,对三环道路交通拥堵持续时间进行了估计.结果表明:三环各路段的拥堵持续时间56%在4 min以内,90%在12 min之内;当拥堵持续时间超过12 mi... 详细信息

采用生存分析的非参数方法,建立基于风险的交通拥堵持续时间模型,根据北京市三环快速路的交通流数据,对三环道路交通拥堵持续时间进行了估计.结果表明:三环各路段的拥堵持续时间56%在4 min以内,90%在12 min之内;当拥堵持续时间超过12 min之后拥堵结束的可能性小于10%.外环比内环更容易发生拥堵,但当拥堵发生后内环的拥堵持续时间更长.

关键词：城市道路交通拥堵持续时间非参数方法

Paleozoic Multi-Stage Magmatic Events Related to Proto-Tethys and Paleo-Tethys Evolution:Insights from Intrusive Rocks in the Eastern Altyn Orogen,NW China

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Journal of Earth Science 2024年第4期35卷 1130-1148页

作者： Jiyong Li Yanqing Xia Xilong Zhang Haoyuan Jiang Tianzhu Lei Yongchao Wang Yanhong Liu Shanpin Liu xiaobao Zhang Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou730000China Key Laboratory of Petroleum Resources Gansu ProvinceLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

Abundant mafic-felsic intrusions distributed in the Altyn Orogen record orogenic histories related to Proto-Tethys and Paleo-Tethys *** U-Pb dating of the intrusive rocks in the eastern Altyn Orogen identifies at least three major tectono-magmatic episodes,yielding ages of∼426,∼376–373 and∼269–254 *** first two emplacement episodes correspond to the post-collisional magmatism in the Altyn ***∼426 Ma granitoids possess adakitic characteristics coupled with enriched isotopes,suggesting that they originated from partial melting of thickened lower continental crust induced by upwelling asthenospheric mantle after slab break-off of the South Altyn Ocean ***,the∼376–373 Ma mafic-intermediate rocks and coeval granitoids represent a large thermal event that involved mantle melting with induced new juvenile lower continental crust melting in a post-collisional extensional ***,the∼254 Ma diabase dykes intruded into the∼269 Ma granitoids,which were related to the widespread Late Paleozoic magmatism resulting from Paleo-Tethys Ocean ***-collisional magmatism in the Altyn Orogen significantly enhances understanding of the tectono-magmatic evolution in the northern Tibetan *** penetrative influence of Paleo-Tethys Ocean subduction was more extensive than previously thought.

关键词： Proto-Tethys Paleo-Tethys Altyn Orogen multi-stage magmatic events magnetic cores

Discovery of Trametinib as an orchestrator for cytoskeletal vimentin remodeling

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Journal of Molecular Cell Biology 2024年第3期16卷 24-34页

作者： Shuangshuang Zhao Zhifang Li Qian Zhang Yue Zhang Jiali Zhang Gaofeng Fan xiaobao Cao Yaming Jiu Unit of Cell Biology and Imaging Study of Pathogen Host Interaction The Center for MicrobesDevelopment and HealthKey Laboratory of Molecular Virology and ImmunologyShanghai Institute of Immunity and InfectionChinese Academy of SciencesShanghai 200031China Guangzhou National Laboratory Guangzhou 510005China University of Chinese Academy of Sciences Beĳing 100049China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China

The dynamic remodeling of the cytoskeletal network of vimentin intermediate filaments supports various cellular functions,including cell morphology,elasticity,migration,organelle localization,and resistance against mechanical or pathological *** available chemicals targeting vimentin predominantly induce network reorganization and shrinkage around the *** tools for long-term manipulation of vimentin network dispersion in living cells are still lacking,limiting in-depth studies on vimentin function and potential therapeutic ***,we verified that a commercially available small molecule,trametinib,is capable of inducing spatial spreading of the cellular vimentin network without affecting its transcriptional or Translational *** evidence confirmed its low cytotoxicity and similar effects on different cell ***,Trametinib has no impact on the other two cytoskeletal systems,actin filaments and the microtubule ***,Trametinib regulates vimentin network dispersion rapidly and efficiently,with effects persisting for up to 48 h after drug *** also ruled out the possibility that Trametinib directly affects the phosphorylation level of *** summary,we identified an unprecedented regulator Trametinib,which is capable of spreading the vimentin network toward the cell periphery,and thus complemented the existing repertoire of vimentin remodeling drugs in the field of cytoskeletal research.

关键词： vimentin intermediate filaments cytoskeleton small molecule network reorganization