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考虑收缩徐变的混凝土T梁桥解联拼接效应分析及支座优化布置 被引量:3
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作者 阳先全 张龙 常红航 《世界桥梁》 北大核心 2015年第2期72-78,共7页
为降低新、旧混凝土收缩徐变对长联混凝土T梁桥横向拼接的影响,指导其合理地拼接,以某22跨1联、跨径25m的混凝土T梁桥拓宽工程为背景,采用有限元法建立其横向拼接的空间模型,分析4种解联方案(1联22跨,2联11跨,4联5、6跨,6联2、4跨)下新... 为降低新、旧混凝土收缩徐变对长联混凝土T梁桥横向拼接的影响,指导其合理地拼接,以某22跨1联、跨径25m的混凝土T梁桥拓宽工程为背景,采用有限元法建立其横向拼接的空间模型,分析4种解联方案(1联22跨,2联11跨,4联5、6跨,6联2、4跨)下新旧混凝土收缩徐变差引起的结构纵、横向效应。结果表明:拼接后,新旧混凝土收缩徐变差在旧桥结构内产生显著的纵、横向效应,直接拼接或解为2联拼接时,最大横向位移均超出支座限值,结构甚至存在落梁风险,且旧桥外边梁和次边梁轴向拉、压力并存,受力较复杂;将旧桥解为100m和150m的短联后拼接可显著减小结构横向效应,且纵向受力简单、均匀。采用最小应变能准则法和目标优化函数法,对解为100m一联方案的支座布置进行优化。 展开更多
关键词 预应力钢筋混凝土桥 T形梁 收缩徐变 解联拼接 支座布置优化 变形 轴力 应变能 有限元法
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新型解联剂及再生助剂用量对废胎面胶胶粉再生效果的影响
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作者 郭磊 杨超 +2 位作者 徐小林 袁浪 汪传生 《合成橡胶工业》 CAS CSCD 北大核心 2015年第5期368-371,共4页
采用自主研发的双螺杆挤出机对废胎面胶胶粉进行再生,研究了新型解联剂以及活化剂580、石蜡油和柠檬烯等再生助剂的用量对再生胶力学性能的影响。结果表明,适量的新型解联剂、活化剂580、石蜡油和柠檬烯能够提高再生胶的力学性能,当再... 采用自主研发的双螺杆挤出机对废胎面胶胶粉进行再生,研究了新型解联剂以及活化剂580、石蜡油和柠檬烯等再生助剂的用量对再生胶力学性能的影响。结果表明,适量的新型解联剂、活化剂580、石蜡油和柠檬烯能够提高再生胶的力学性能,当再生胶基础配方中新型解联剂、活化剂580、石蜡油、柠檬烯用量分别为3,2,3,1份时,废胶粉的再生效果最佳,综合力学性能最好。 展开更多
关键词 胶粉 再生 解联 活化剂 石蜡油 柠檬烯 力学性能
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连续桥梁顶升改造解联方案分析 被引量:5
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作者 杨洋 吴二军 +1 位作者 蓝戊己 王建永 《水利与建筑工程学报》 2013年第6期35-39,共5页
结合佛开高速公路北江大桥北引桥7跨连续梁和南引桥6跨连续梁的顶升改造工程,介绍了以解联后的桥型、内力和变形为解联较优方案的三要素,针对南北引桥分别提出4种解联方案,进行了此三要素的对比分析,确定了最优方案并给出了解联具体施... 结合佛开高速公路北江大桥北引桥7跨连续梁和南引桥6跨连续梁的顶升改造工程,介绍了以解联后的桥型、内力和变形为解联较优方案的三要素,针对南北引桥分别提出4种解联方案,进行了此三要素的对比分析,确定了最优方案并给出了解联具体施工过程,为今后类似工程提供参考。 展开更多
关键词 连续桥梁 顶升改造 解联方案 对比分析
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连续梁顶推施工解联部位可靠度分析 被引量:1
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作者 谭杰 《中外公路》 北大核心 2015年第4期227-230,共4页
在顶推施工中,由于解联部位受力的暂时性和临时性,在不利荷载作用下易达到极限状态。为探讨其在施工过程中的安全可靠度,该文以湘阴大桥的顶推施工为背景,分析了解联部位的结构特点和受力特点,运用结构力学方法建立该截面的可靠分析模型... 在顶推施工中,由于解联部位受力的暂时性和临时性,在不利荷载作用下易达到极限状态。为探讨其在施工过程中的安全可靠度,该文以湘阴大桥的顶推施工为背景,分析了解联部位的结构特点和受力特点,运用结构力学方法建立该截面的可靠分析模型,进行了可靠模型的分析计算,得出该模型的可靠指标符合规范安全要求,并对设计参数和变量的敏感度进行了分析,揭示了混凝土抗压强度不定性参数对可靠度的影响比较突出。 展开更多
关键词 连续梁桥 解联 可靠指标 敏感性分析
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小孔梯段微差爆破在马房大桥解联中的应用
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作者 符瑞钦 《公路与汽运》 2003年第6期62-63,共2页
介绍了 32 1国道扩建工程肇庆马房大桥体系转换中临时支座爆破方案的设计 。
关键词 桥梁 微差爆破 解联 爆破方案 安全措施
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贺江大桥联体挂篮改造及解联工艺
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作者 李运铭 《低碳世界》 2018年第7期291-292,共2页
广佛肇高速公路贺江大桥连续钢构施工采用挂篮悬臂浇筑施工,利用原有菱形挂篮进行改造,针对贺江大桥0#、1#块长度较短,设计联体挂篮进行2#块的施工。本文结合此实际工程,首先对联体挂篮改造设计进行了分析,然后对联体挂篮解联工艺进行... 广佛肇高速公路贺江大桥连续钢构施工采用挂篮悬臂浇筑施工,利用原有菱形挂篮进行改造,针对贺江大桥0#、1#块长度较短,设计联体挂篮进行2#块的施工。本文结合此实际工程,首先对联体挂篮改造设计进行了分析,然后对联体挂篮解联工艺进行了讨论,工程施工后满足了施工要求,保证了工程顺利施工,可供参考。 展开更多
关键词 联体挂篮 解联 后压杆改造
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大黄提取片对高脂饮食诱导肥胖大鼠能量代谢的影响 被引量:6
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作者 查兵兵 张烁 +3 位作者 焦东海 江霖 陈接根 李益明 《上海中医药杂志》 北大核心 2006年第10期57-59,共3页
目的观察大黄提取片对高脂饮食诱导肥胖大鼠骨骼肌解偶联蛋白3(UCP3)及能量代谢的影响,以探讨大黄的减肥作用机制。方法给饮食诱导肥胖大鼠灌服低、中、高剂量大黄提取片(200、400、800mg·kg-·1d-1),测定大鼠肥胖指标,显微镜... 目的观察大黄提取片对高脂饮食诱导肥胖大鼠骨骼肌解偶联蛋白3(UCP3)及能量代谢的影响,以探讨大黄的减肥作用机制。方法给饮食诱导肥胖大鼠灌服低、中、高剂量大黄提取片(200、400、800mg·kg-·1d-1),测定大鼠肥胖指标,显微镜下观察脂肪细胞大小,应用Real-timePCR和Westernblot检测大鼠骨骼肌UCP3表达量,高效液相色谱法(HPLC)测定大鼠骨骼肌细胞能荷值(EC)。结果大黄提取片呈剂量依赖性的增强减肥作用,高剂量大黄提取片能明显减轻饮食诱导肥胖大鼠腹腔脂肪重量和体重(P<0.05),降低Lee’s指数(P<0.05),减小脂肪细胞最大直径与最小直径(P<0.05),明显增加骨骼肌UCP3表达(P<0.05),并降低骨骼肌细胞能荷水平(P<0.05)。结论大黄提取片可能通过增加肥胖大鼠骨骼肌中UCP3表达﹑促进细胞能量代谢而有效减肥。 展开更多
关键词 肥胖 大黄提取物 解联蛋白 细胞能荷 动物实验
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母猪繁殖性能相关5个候选基因的PCR-RFLP多态性研究 被引量:5
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作者 吴华莉 涂尾龙 +4 位作者 曹建国 都启晶 常华 羊兆洪 谈永松 《上海农业学报》 CSCD 2018年第1期66-73,共8页
为了比较ESR、NCOA1、ADAMTS1、FUT1和RBP4基因对猪繁殖性能的效应大小,采用PCR-RFLP技术,分别检测了杜洛克、长白和大白群体内5个基因的基因型频率和等位基因频率,并分析不同基因型与3个猪群体的总产仔数(TNB)、产活仔数(NBA)和出生窝... 为了比较ESR、NCOA1、ADAMTS1、FUT1和RBP4基因对猪繁殖性能的效应大小,采用PCR-RFLP技术,分别检测了杜洛克、长白和大白群体内5个基因的基因型频率和等位基因频率,并分析不同基因型与3个猪群体的总产仔数(TNB)、产活仔数(NBA)和出生窝重(BLW)相关性。结果表明:对猪繁殖性能影响效应最大的是NCOA1和RBP4基因,其次是FUT1和ADAMTS1基因,最小的是ESR基因。NCOA1基因在杜洛克和大白群体内AA型的NBA比BB型的分别高1.11和1.92头,AA型的TNB比BB型的分别高1.18头和0.53头。RBP4基因在3个猪群体内AA型的TNB比BB型的高0.53—0.86,在杜洛克和大白群体内AA型的NBA比BB型的分别高1.1头和1.29头。FUT1在杜洛克和大白群体内AA型的TNB比CBB型的分别高0.47和0.56),AA型的NBA比BB型的分别高0.76头和1.06头。ADAMTS1基因在3个猪群体内AB型的TNB比AA型的高0.67—0.88,AB型的NBA比AA型的高0.54—0.86。在大白群体内ESR基因的BB型的TNB、NBA比AA型的分别高0.36头和0.41头。5个基因的不同基因型对3个猪群体BLW影响不显著。 展开更多
关键词 繁殖性状 雌激素受体(ESR) 核受体辅激活蛋白1(NCOA1) 含凝血酶敏感蛋白模体的去解联金属蛋白酶1基因(ADAMTS1) 岩藻糖转移酶1基因(FUT1) 视黄醇结合蛋白4基因(RBP4)
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丁基胶囊再生新工艺的影响因素 被引量:1
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作者 曾宪奎 郭磊 +1 位作者 边慧光 汪传生 《合成橡胶工业》 CAS CSCD 2009年第4期321-324,共4页
将废旧丁基橡胶(IIR)胶囊和解联剂、石腊油通过自制的同步转子实验密炼机混炼制备了IIR再生胶,考察了填充系数(β)、转子转速、混炼时间、解联剂及石蜡油用量对IIR再生胶硫化胶物理机械性能的影响。结果表明:当在β值为1、转子转速为100... 将废旧丁基橡胶(IIR)胶囊和解联剂、石腊油通过自制的同步转子实验密炼机混炼制备了IIR再生胶,考察了填充系数(β)、转子转速、混炼时间、解联剂及石蜡油用量对IIR再生胶硫化胶物理机械性能的影响。结果表明:当在β值为1、转子转速为100 r/min、混炼时间为15 min、解联剂为3.5份、石蜡油为5份的工艺条件下,IIR再生胶硫化胶的物理机械性能达到最佳。 展开更多
关键词 废旧丁基胶囊 解联 混炼 再生胶 物理机械性能
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不同力化学法制得胎面再生胶的试验研究 被引量:1
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作者 汪传生 袁浪 +2 位作者 胡纪全 刘营 程耀华 《世界橡胶工业》 2017年第7期7-12,共6页
分别采用密炼机、串联式密炼机和密炼挤出一体机对废胎面胶胶粉进行再生,对比研究自制再生胶和市售再生胶与不同比例天然橡胶共混试验。结果表明,添加自主研发的再生解联剂,三种力化学法均能实现废橡胶低温再生,且采用密炼挤出一体机制... 分别采用密炼机、串联式密炼机和密炼挤出一体机对废胎面胶胶粉进行再生,对比研究自制再生胶和市售再生胶与不同比例天然橡胶共混试验。结果表明,添加自主研发的再生解联剂,三种力化学法均能实现废橡胶低温再生,且采用密炼挤出一体机制得再生胶综合性能最好,共混性能优于市售再生胶。 展开更多
关键词 废胎面胶 解联 力化学法 低温再生
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ADAMs的结构和功能 被引量:4
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作者 徐存拴 张为民 +3 位作者 林俊堂 胡轶红 梁卫红 李玉昌 《自然科学进展(国家重点实验室通讯)》 北大核心 2001年第9期902-908,共7页
ADAMs是近几年发现的一类锚定于细胞膜的跨膜糖蛋白,含多个结构域并具有多种功能,它们的结构域包括信号肽区、前调控区、金属蛋白水解酶区、解联蛋白区、富半胱氨酸区、上皮生长因子区、跨膜区和胞内区等;它们的功能包括蛋白水解、分子... ADAMs是近几年发现的一类锚定于细胞膜的跨膜糖蛋白,含多个结构域并具有多种功能,它们的结构域包括信号肽区、前调控区、金属蛋白水解酶区、解联蛋白区、富半胱氨酸区、上皮生长因子区、跨膜区和胞内区等;它们的功能包括蛋白水解、分子修饰、分子释放、细胞与细胞和细胞与基质相互作用、细胞识别、细胞内信号传导、细胞间通讯等,简要总结了ADAMs一级结构、高级结构、理化性质、结构区组成、各结构区功能以及ADAMs在肝再生过程中的变化等方面的研究进展。 展开更多
关键词 ADAMS 金属蛋白水解酶 信号肽 解联蛋白 整联蛋白 跨膜糖蛋白 结构域 一级结构
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动车组自动联解控制盘PLC程序设计及研究 被引量:2
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作者 杨海军 黄志辉 《铁道机车车辆》 2007年第4期46-48,共3页
采用PLC作为控制系统的核心,实现了高速电动车组自动联挂与解联控制。介绍了动车组控制系统的组成,控制系统的实现方法研究,最终通过试验模拟调试以及装车试验,验证了程序的正确性。
关键词 联挂与解联控制 实现方法 可编程控制器
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Reservoir detection based on EMD and correlation dimension 被引量:3
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作者 文晓涛 贺振华 黄德济 《Applied Geophysics》 SCIE CSCD 2009年第1期70-76,103,104,共9页
In hydrocarbon reservoirs, seismic waveforms become complex and the correlation dimension becomes smaller. Seismic waves are signals with a definite frequency bandwidth and the waveform is affected by all the frequenc... In hydrocarbon reservoirs, seismic waveforms become complex and the correlation dimension becomes smaller. Seismic waves are signals with a definite frequency bandwidth and the waveform is affected by all the frequency components in the band. The results will not define the reservoir well if we calculate correlation dimension directly. In this paper, we present a method that integrates empirical mode decomposition (EMD) and correlation dimension. EMD is used to decompose the seismic waves and calculate the correlation dimension of every intrinsic mode function (IMF) component of the decomposed wave. Comparing the results with reservoirs identified by known wells, the most effective IMF is chosen and used to predict the reservoir. The method is applied in the Triassic Zhongyou group in the XX area of the Tahe oil field with quite good results. 展开更多
关键词 empirical mode decomposition correlation dimension intrinsic mode function RESERVOIR
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Kinematics and dynamics analysis of a 3-7R parallel decoupling mechanism 被引量:2
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作者 郑建勇 史金飞 +1 位作者 张志胜 李为民 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期183-187,共5页
One kind of movable-pair analysis method is adopted to analyze the configuration of a 3-7R (revolute-pair) parallel decoupling mechanism, and the mechanism's characteristics are summarized. The mechanism has three ... One kind of movable-pair analysis method is adopted to analyze the configuration of a 3-7R (revolute-pair) parallel decoupling mechanism, and the mechanism's characteristics are summarized. The mechanism has three orthogonal distributional branch-chains, and all movable pairs are rotational joints. The movable platform of the mechanism has x, y, z translational decoupling directions. Furthermore, in order to verify the mechanism's decoupling characteristics, the mechanism's kinematics analysis is solved, and the mechanism's direct/inverse kinematics model, input/output velocities and accelerations are deduced, which confirm its decoupling movement characteristics. Finally, one kind of mechanism link decomposed-integrated approach is adopted, and the mechanism's dynamics model is completed with the Lagrange method, which also proves its decoupling force characteristics. All of these works provide significant theory for the further study of the mechanism's control strategy, design, path planning etc. 展开更多
关键词 3-7R parallel decoupling mechanism KINEMATICS DYNAMICS DECOUPLING
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Study on Enhancement of PCBs Desorption in Soil by Surfactants 被引量:11
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作者 黄卫红 李勇 杨岚钦 《Agricultural Science & Technology》 CAS 2010年第1期73-76,共4页
[Objective]The aim of this paper was to provide theoretical basis for study on enhancement of surfactants to desorption of PCBs from soil. [Method]The desorption effects of surfactants SDBs,Tween 80,HTAB on PCBs were ... [Objective]The aim of this paper was to provide theoretical basis for study on enhancement of surfactants to desorption of PCBs from soil. [Method]The desorption effects of surfactants SDBs,Tween 80,HTAB on PCBs were studied as well as their distribution in water and soil. Effects of rationing on desorption of PCBs were also analyzed. [Result]The potential of single surfactant to enhance the desorption of PCBs from soil in order was Tween 80 SDBS HTAB. Three surfactants were largely adsorbed on soil and the sorption followed HTABTween 80SDBS. The desorption of PCBs increased significantly and linearly with the increase of aqueous micelle concentration of surfactants. [Conclusion]Enhancing effect of three surfactants on PCBs desorption were obtained,which will provide theoretical basis for further analyzing. 展开更多
关键词 SURFACTANT PCBS DESORPTION Aqueous micelle concentration
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Insulation fault diagnosis based on group grey relational grade analysis method for power transformers 被引量:5
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作者 董立新 肖登明 刘奕路 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期175-179,共5页
Utilising dissolved gases analysis, a new insulation fault diagnosis methodfor power transformers is proposed. This method is based on the group grey relational grade analysismethod. First, according to the fault type... Utilising dissolved gases analysis, a new insulation fault diagnosis methodfor power transformers is proposed. This method is based on the group grey relational grade analysismethod. First, according to the fault type and grey reference sequence structure, some typicalfault samples are divided into several sets of grey reference sequences. These sets are structuredas one grey reference sequence group. Secondly, according to a new calculation method of the greyrelational coefficient, the individual relational coefficient and grade are computed. Then accordingto the given calculation method for the group grey relation grade, the group grey relational gradeis computed and the group grey relational grade matrix is structured. Finally, according to therelational sequence, the insulation fault is identified for power transformers. The results of alarge quantity of instant analyses show that the proposed method has higher diagnosis accuracy andreliability than the three-ratio method and the traditional grey relational method. It has goodclassified diagnosis ability and reliability. 展开更多
关键词 dissolved gases analysis group grey relational grade fault diagnosis
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Influence of K + on the Coupling Between ATP Hydrolysis and Proton Transport by the Plasma Membrane H +_ATPase from Soybean Hypocotyls 被引量:1
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作者 邱全胜 《Acta Botanica Sinica》 CSCD 1999年第9期962-966,共5页
The plasma membrane vesicles were purified from soybean (Glycine max L.) hypocotyls by two_phase partitioning methods. The stimulatory effects of K + on the coupling between ATP hydrolysis and proton transport by th... The plasma membrane vesicles were purified from soybean (Glycine max L.) hypocotyls by two_phase partitioning methods. The stimulatory effects of K + on the coupling between ATP hydrolysis and proton transport by the plasma membrane H +_ATPase were studied. The results showed that the proton transport activity was increased by 850% in the presence of 100 mmol/L KCl, while ATP hydrolytic activity was only increased by 28.2%. Kinetic studies showed that K m of ATP hydrolysis decreased from 1.14 to 0.7 mmol/L, while V max of ATP hydrolysis increased from 285.7 to 344.8 nmol Pi·mg -1 protein·min -1 in the presence of KCl. Experiments showed that the optimum pH was 6.5 and 6.0 in the presence and absence of KCl, respectively. Further studies revealed that K + could promote the inhibitory effects of hydroxylamines and vanadates on the ATP hydrolytic activity. The above results suggested that K + could regulate the coupling between ATP hydrolysis and proton transport of the plasma membrane H +_ATPase through modulating the structure and function of the kinase and phosphatase domains of the plasma membrane H +_ATPase. 展开更多
关键词 Soybean hypocotyl Plasma membrane H +_ATPase K + ATP hydrolysis Proton transport COUPLING
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试析《说文解字》部首系联的纲原则
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作者 左思民 《中国文字研究》 CSSCI 2015年第2期96-103,共8页
本文通过对《说文解字》部首系联情况的考察和探求,提出在纲层次上,该书部首既非"据形系联",也非简单的以意系联,而是采用了"具表征意的数算符号的有序系联"原则,简称"以数系联"。这表现为借助以"一"到"十"为代表的十进制记... 本文通过对《说文解字》部首系联情况的考察和探求,提出在纲层次上,该书部首既非"据形系联",也非简单的以意系联,而是采用了"具表征意的数算符号的有序系联"原则,简称"以数系联"。这表现为借助以"一"到"十"为代表的十进制记数系统、天干和地支这三个数算系统,通过它们之间的先后系联以及这三个系统内部相关部首之间的系联,构成了两个基本块:以"一"头"二"尾(表征了"天"头"地"尾)为代表的"一厽块",以及以天干地支为主的"甲亥块"。"一厽块"加上"甲亥块",加上它们所含的若干内包小块,再加上居于这两个基本块之间的微小块"四嘼块",最终组成了一个多层、多块的部首系联格局,构建了《说文解字》全书部首系联的骨干框架。本文认为,许慎构建这样的部首系联格局并非偶然,而是欲借此表征他所"认识"到的宇宙运行演化的次序和规律。 展开更多
关键词 说文解字 部首 系联
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Data Fusion in Distributed Multi-sensor System 被引量:7
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作者 GUOHang YUMin 《Geo-Spatial Information Science》 2004年第3期214-217,234,共5页
This paper presents a data fusion method in distributed multi-sensor system including GPS and INS sensors’ data processing. First, a residual χ 2 \|test strategy with the corresponding algorithm is designed. Then a ... This paper presents a data fusion method in distributed multi-sensor system including GPS and INS sensors’ data processing. First, a residual χ 2 \|test strategy with the corresponding algorithm is designed. Then a coefficient matrices calculation method of the information sharing principle is derived. Finally, the federated Kalman filter is used to combine these independent, parallel, real\|time data. A pseudolite (PL) simulation example is given. 展开更多
关键词 PSEUDOLITE distributed multi-sensor system data fusion federated Kalman filtering
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ATF4 regulates lipid metabolism and thermogenesis 被引量:16
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作者 Chunxia Wang Zhiying Huang Ying Du Ying Cheng Shanghai Chen Feifan Guo 《Cell Research》 SCIE CAS CSCD 2010年第2期174-184,共11页
Activating transcription factor 4 (ATF4) has been shown to play key roles in many physiological processes. There are no reports, however, demonstrating a direct link between ATF4 and lipid metabolism. We noticed tha... Activating transcription factor 4 (ATF4) has been shown to play key roles in many physiological processes. There are no reports, however, demonstrating a direct link between ATF4 and lipid metabolism. We noticed that Atf4- deficient mice are lean, suggesting a possible role for ATF4 in regulating lipid metabolism. The goal of our current study is to investigate the involvement of ATF4 in lipid metabolism and elucidate the underlying mechanisms. Studies using Atf4-deficient mice revealed increased energy expenditure, as measured by oxygen consumption. These mice also showed increases in lipolysis, expression of uncoupling protein 2 (UCP2) and p-oxidation genes and decreases in expression of lipogenic genes in white adipose tissue (WAT), suggesting increased utilization and decreased synthesis of fatty acids, respectively. Expression of UCP1, 2 and 3 was also increased in brown adipose tissue (BAT), suggesting increased thermogenesis. The effect of ATF4 deletion on expression of UCPs in BAT suggests that increased thermogenesis may underlie increased energy expenditure. Thus, our study identifies a possible new function for ATF4 in regulating lipid metabolism and thermogenesis. 展开更多
关键词 ATF4 lipid metabolism THERMOGENESIS WAT BAT
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