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Rare earth elements-rich phase and enriching mechanism in sediments from CC area, the Pacific Ocean

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Acta Oceanologica Sinica 2001年第2期20卷 209-214页

作者： Meng Xianwei, Chen Zhihua, Wang Xiangqin, Liu na (1. First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 2. Key Lab. of Marine Science and Numerical Modelling, State Oceanic Administration, Qingdao 266003, China) First Institute of Oceanography State Oceanic Administration Key Lab. of Marine Sci./Numerical Mo Qingdao 266003 China

Compared to North American shale composition (naSC), REE contents of sediments from the CC area in the Pacific Ocean are obviously high except that cerium has equal content to that of naSC. Three-valence rare earth elements were completely enriched in phosphate-phase and cerium in iron-phase. Rare earth elements in the sediments were originally derived from seawater. During lithi- genic and minerogenic processes of metalliferous nodules, three-valence rare earth elements in sediments mobilized and incorporated into sediments as authigenous biogenic-apatite, while cerium had change from Ce3+ to Ce4+ and directly precipitated from seawater and entered metalliferous nodules and caused Ce anomalies in REE pattern in sediments.

关键词： CC area of the Pacific Ocean sediments rare earth elements REE- rich phase enriching mechanism

Flexibility Discrete Dynamic Bayesian Networks modeling and Inference algorithm

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Flexibility Discrete Dynamic Bayesian Networks modeling and ...

第24届中国控制与决策会议

作者： REN Jia 1., TANG Tao 1., WANG na 2 1. College of Information Sciences & Technology, Hainan University, Haikou, 570228,China2. College of Energy and Electrical Engineering, Xi''an Siyuan University, Xian,71.000 China

Directly applying Discrete Dynamic Bayesian Networks to time-varying environment is highly complex, it mainly dues to : application environment with mutant characteristics;network structure and parameters needing to have the variation;adapt to the uncertainty of sensor observations . To meet the above requirements, proposing the concept of Flexible Discrete Dynamic Bayesian Network, designing a mechanism of flexible model based on muti-model for the discrete-time systems under mutant environment. Based on the above, applying the Forward algorithm to fulfill Flexible Discrete Dynamic Bayesian Network probabilistic inference thus can be able to use uncertainty observations information to obtain a reliable state estimation.

关键词： Mutation Environments Dynamic Bayesian Networks Flexibility Dynamic Bayesian Networks Multi-model

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一种挖掘最大频繁子图的新算法

系统仿真学报 2008年第18期20卷 4872-4877页

作者：王映龙杨炳儒宋泽峰陈卓李琳娜北京科技大学信息工程学院

如何从大量的图中挖掘出令人感兴趣的子图模式已经成为数据挖掘领域研究的热点之一.由于其内在的计算复杂性,挖掘全部频繁子图非常困难,且得到的频繁子图过多,影响着结果的理解和应用.解决方案之一是挖掘最大频繁子图.在经典的Apriori... 详细信息

如何从大量的图中挖掘出令人感兴趣的子图模式已经成为数据挖掘领域研究的热点之一.由于其内在的计算复杂性,挖掘全部频繁子图非常困难,且得到的频繁子图过多,影响着结果的理解和应用.解决方案之一是挖掘最大频繁子图.在经典的Apriori算法的基础上,提出了一种挖掘最大频繁子图的新算法Apriori-MaxGraph.首先给出了一种新的、用于计算图的邻接矩阵规范编码的结点排序策略,大大降低了求图规范编码的复杂度,并可以加速子图规范编码序列匹配的速度.其次,针对最大频繁子图,对候选子图的生成进行了规范.最后,采用双向搜索与剪枝策略,大大减小了搜索空间,提高了算法的效率.实验结果表明,Apriori-MaxGraph算法具有较高的挖掘效率.

关键词：数据挖掘最大频繁子图邻接矩阵规范编码

Explicit analytical solutions fof transport equations considering non-Fourier and non-Fick effects in porous media

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Progress in natural Science:Materials International 2005年第6期 545-549页

作者： GOU Chenhua 1.2 , CAI Ruixian1.* and ZHANG na1.1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 1.0080, China 2. Graduate School, Chinese Academy of Sciences, Beijing 1.0080, China)

Based on the method of separation variables with addition developed in recent years, new methods of separation variables are proposed, and two algebraically explicit analytical solutions to the general partial differential equation set of non-Fourier and non-Fick heat and mass transfer in porous media drying are derived. The physical meaning of these solutions is simple and clear, and they are valuable for computational heat and mass transfer as benchmark solutions.

关键词： non-Fourier effects non-Fick effects porous media heat and mass transfer analytical solution.

CRABP1.mediated non-canonical retinoic acid signaling in motor neurons and neural stem cells

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Neural Regeneration Research 2024年第6期19卷 1169-1170页

作者： Li-na Wei Department of Pharmacology University of Minnesota Medical SchoolMinneapolisMNUSA

Retinoic acid(RA),the active metabolite of vitamin A(the retinoids),elicits a wide spectrum of biological activities critical to the development and health of most of the organ systems including the nervous systems(Corcoran et al.,2002).The effects of RA are mediated by two very distinct pathways;the first is manifested in the nucleus by binding to a large family of nuclear RA receptors(RARs)to regulate proper expression of RAtargeted genes.

关键词： canonical spectrum critical

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厄贝沙坦治疗轻、中度高血压病

中国新药与临床杂志 2002年第7期21卷 407-410页

作者：刘红军常玲王鸿懿王伟孙伟娜北方交通大学医院北京100044 北京大学附属人民医院心内科北京100034

目的 :评价国产厄贝沙坦对轻、中度原发性高血压的降压疗效及安全性。方法 :为双盲对照试验。轻、中度原发性高血压病人 40例 (男性 3 2例女性 8例 ,年龄 49a±s 1.0a)随机分为厄贝沙坦组和缬沙坦组各 2 0例 ,分别给予厄贝沙坦 1.5 0mg ... 详细信息

目的 :评价国产厄贝沙坦对轻、中度原发性高血压的降压疗效及安全性。方法 :为双盲对照试验。轻、中度原发性高血压病人 40例 (男性 3 2例女性 8例 ,年龄 49a±s 1.0a)随机分为厄贝沙坦组和缬沙坦组各 2 0例 ,分别给予厄贝沙坦 1.5 0mg ,po,qd或缬沙坦 80mg ,po,qd ;2wk后按血压决定维持原剂量或厄贝沙坦增加到 3 0 0mg ,po,qd或缬沙坦增加为 1.60mg,po,qd;总疗程 4wk。结果 :厄贝沙坦治疗 4wk末的总有效率为 75 % ,收缩压下降 (2 .7± 1..8)kPa,舒张压下降 (1..5± 0 .8)kPa均P 1.;不良反应的发生率为 5 %。结论 :国产厄贝沙坦治疗轻、中度原发性高血压的短期疗效明显 ,每日服药 1. ,疗效持久。

关键词：厄贝沙坦缬沙坦高血压治疗

Public transport inclusion and active aging: A systematic review on elderly mobility

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 312-347页

作者： na Zhang Qi Yang School of Humanities Chang'an UniversityXi'an 710064China School of Transportation Engineering Chang'an UniversityXi'an 710064China School of Economics and Management Chang'an UniversityXi'an 710064China

Global aging has brought attention to addressing the elderly mobility dilemma,and a commitment to address inclusive transport in *** inclusion for older adults aims at establishing an age-friendly transport *** a direct policy goal and promoting active aging as an indirect social goal,to help older populations gain access to transport and social *** on the analysis of scientific knowledge mapping over the past 30 years,this study visualizes the hotspots and trends in elderly mobility *** a qualitative analysis of 1.8 papers,this paper reviews the theoretical foundations for transport inclusion and three themes of elderly mobility research,proposes a framework for public transport(PT)inclusion research as well as future research *** study suggests that transport inclusion can help enhance elderly health,social participation,and subjective *** can improve their travel opportunities for active aging in four ways:opportunity accessibility,physical accessibility,age-friendly informationalization,and cost *** research should pay attention to examining the mechanism of perceived transport inclusion on active aging,expanding the multilevel research space of the capability approach(CA),and exploring the subjectiveobjective integrated research model for PT *** research contributes to the overall knowledge of the theoretical and empirical researches on PT inclusion for the elderly and promotes the integrated application of interdisciplinary knowledge in the field.

关键词： Transportation engineering Elderly mobility Transport-related social exclusion Transport inclusion Active aging

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格上传递矩阵的性质

四川师范大学学报（自然科学版） 2009年第6期32卷 751-756页

作者：胡先富李娜重庆城市管理职业学院信息工程学院重庆401331 四川师范大学数学与软件科学学院四川成都610066

假设格L是有最小元0的分配格,x,y∈L,定义x与y的二元运算x■y为:当x≤y时,x■y=0;否则,x■y=x.定义格上矩阵(Rij)n×n与(Sij)n×n的合成为(RijSij)n×n.对幂零矩阵R,证明了(R/R)+=R+;对非自反传递矩阵R,证明了R/R≤S≤R与R/R=S/R等价,其... 详细信息

假设格L是有最小元0的分配格,x,y∈L,定义x与y的二元运算x■y为:当x≤y时,x■y=0;否则,x■y=x.定义格上矩阵(Rij)n×n与(Sij)n×n的合成为(RijSij)n×n.对幂零矩阵R,证明了(R/R)+=R+;对非自反传递矩阵R,证明了R/R≤S≤R与R/R=S/R等价,其中R/S=R■(R⊙S),⊙是sup-inf合成算子,R+是R的传递闭包.

关键词：分配格矩阵传递矩阵矩阵的传递闭包幂零矩阵

气相色谱-质谱联用测定柴油机排气微粒中的可溶性有机组分

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色谱 2004年第4期22卷 445-448页

作者：王桂华王钧效黄学政陆家祥刘娜山东大学能源与动力工程学院山东济南250061 宏大研究院有限公司北京100176 山东省能源建筑设计院山东济南250014

采用气相色谱质谱联用技术 (GC/MS)对柴油机排气微粒中的可溶性有机组分 (SOF)进行了分离分析。SOF分析液样品采用超声提取法制取。GC条件为 :SE 5 0型石英毛细管色谱柱 (30m× 0 2mmi d × 0 2 μm) ;程序升温 :初始温度 1. 0℃ ,恒... 详细信息

采用气相色谱质谱联用技术 (GC/MS)对柴油机排气微粒中的可溶性有机组分 (SOF)进行了分离分析。SOF分析液样品采用超声提取法制取。GC条件为 :SE 5 0型石英毛细管色谱柱 (30m× 0 2mmi d × 0 2 μm) ;程序升温 :初始温度 1. 0℃ ,恒温 2 0min ,以 4 0℃ /min升至 1. 0℃ ,再以 8℃ /min升至 2 5 0℃ ,恒温 31.75min ;汽化室温度 2 6 0℃ ;载气为氦气 ,柱头压力 4 5kPa ;进样量 1.L。MS条件为 :电子轰击离子源 ,电子轰击能量 70eV ;倍增器电压 1.0 0V ;质量扫描范围 30 0～ 5 0 0u。检测结果表明 :在排气管取样状态下 ,微粒SOF组分中 80 %左右为正烷烃和支链烷烃 ,碳数为 9～ 2 8,余下组分为多环芳香烃 (茚、芴、菲、萘等的同系物 )以及少量其他有机物。实验证实微粒SOF主要组分来源为未燃烧的柴油和进入燃烧室的机油 ,此检测结果为柴油机微粒净化装置的研制及评价提供了一定的实验依据。

关键词：气相色谱-质谱可溶性有机组分柴油机排气微粒柴油废气