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Near-Earth bursty bulk flows and ae index

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Science China(Technological Sciences) 2008年第10期51卷 1704-1712页

作者： W BAUMJOHANN M. W. DUNLOP C. CARR H. RME Space Research Institute Austrian Academy of Sciences Graz Austria Space Sciences Division Rutherford Appleton Laboratory Chilton Didcot UK Imperial College London United Kingdom Centre d'Etude Spatiale des Rayonnements Toulouse France

With the 4-s resolution data of the magnetometer and the ion plasma analyzer on TC-1 from June to November of each year during the period of 2004―2006, we statistically analyzed the occurrence rate of both convective and field-aligned bursty flows (FABFs). A near-Earth bursty bulk flow (NEBBF) occurred during both the quiet time and substorm process. In general, the magnetic field and the plasma density began oscillating with the appearance of the NEBBF associated with a distinct increase of the ae index. The increase of ae index during the NEBBF was more than 100 nT in both quiet time and substorm process. The statistical analysis indicated that the occurrence rates of the FABFs were nearly the same in the dif-ferent stages of the ae index, but the occurrence rate of the NEBBFs was much higher in the growth stage of the ae index, indicating that the NEBBFs were di-rectly related to the growth and expansion phases of the substorm. The observa-tions suggested that the quite large number of BBFs from the mid magnetotail could enter into the near-Earth tail and play important role in triggering the sub-storm onset.

关键词： BBF near-Earth ae index substorm onset

Relationship between FAC at plasma sheet boundary layers and ae index during storms from August to October,2001

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Science China(Technological Sciences) 2008年第7期51卷 842-848页

作者： DUNLOP M Imperial College London London SW7 2AZ UK

Unlike the previous single (dual) satellite observation, the four Clusterll satellites make it possible to directly compute the continuous field-aligned current (FAC) density according to the magnetic data from them and to enable the investigation of the relationship between the FAC and geomagnetic activity. This paper analyzes the observation data when the Cluster satellites crossed the plasma sheet boundary layer (PSBL) in the magnetotail during the two magnetic storms in August to October 2001. According to the data, during the magnetic storms the relationship between the variations of FAC and ae index turned out to be: 1) FAC was obviously increasing during the storms; 2) FAC density was approximately negatively correlated with ae index from the sudden commencement to the early main phase of the storm; 3) they were approximately positively correlated during the late main phase and early recovery phase; 4) they were no apparent correlation during the late recovery phase.

关键词： ionosphere-magnetosphere storm cases FAC ae index

A new processing method for the ae index

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Science China(Technological Sciences) 2008年第10期51卷 1713-1720页

作者： W. BAUMJOHANN M. DUNLOP Space Research Institute Austrian Academy of Sciences Graz Austria Space Sciences Division Rutherford Appleton Laboratory Chilton Didcot United Kingdom

In this paper, we introduce an effective processing method to acquire the time de-rivative of the ae index as a coefficient. Using this coefficient, the ae index can be divided into the four stages: quiet, ascending, descending and active stages. The statistical results show that the ascending and descending stages of the ae index are dominant and occupy two thirds of the whole period. An analysis of the rela-tionship between the occurrence frequencies of the Dst index and ae index in solar cycle 23 shows that the monthly variation of the occurrence frequencies of the ascending stage of ae is closely related to the decrease of the Dst index.

关键词： ae index Dst index FIR filter substorm

Identification of a novel HIV-1 intra-circulating recombinant form 01_ae in China: a descendant of the previously identified CRF01_ae transmission clusters 1 and 6

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Science China(Life Sciences) 2015年第7期58卷 724-726页

作者： NING ChuanYi LI XingGuang TANG WeiMing ZHOU Bo CAI WeiPing TUCKER Joseph D. Guangzhou Eighth People's Hospital & University of North Carolina and China Project Research Center for Regenerative Medicine Guangxi Medical University HIV Molecular Epidemiology and Virology Research Group State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences

Dear Editors,Here, we report a novel HIV-1 intra-circulating recombinant form 01_ae （intra-CRF01_ae： CRF01-1ae/CRF01-6ae） composed of CRF01_ae transmission clusters 1 and 6, which was identified in a heterosexual male from Fujian, with one breakpoint observed in the vif gene. The CRF01_ae region I （HXB2： 868-5184） of the recombinant clustered with CRF01_ae transmission cluster 1, which is mainly circulating among injection drug users （IDUs） and heterosexuals in southern and southwestern China, with the support of a 100% bootstrap value. The CRF01_ae region II （HXB2： 5185-9605） of the recombinant clustered with CRF01_ae transmission cluster 6, which mainly prevails among heterosexuals in southern China, with the support of a 100% bootstrap value. To our knowledge, this is the first detection of a novel HIV-1 intra-CRF01_ae recombinant form （CRF01-1_ae/CRF01-6_ ae） in Fujian, China, which indicates ongoing active HIV-1 transmission among heter- osexuals in this region.

关键词： HIV-1 传输集群识别重组后代 ae

LAS和ae对水生植物损伤的显微和亚显微结构观察

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中国环境科学 2001年第6期21卷 527-530页

作者：刘红玉廖柏寒鲁双庆周朴华杨仁斌湖南农业大学环境科学系湖南长沙410128 长沙大学应用化学与环境保护系湖南长沙410003 湖南农业大学生物技术系湖南长沙410128

利用透射电镜研究了阴离子型表面活性剂LAS和非离子型表面活性剂ae对水生植物水绵、水浮莲的损伤作用.观察发现,在LAS处理液中,水绵细胞壁外层被溶解而消失,载色体的规则螺旋缠绕结构被打乱,集结成团.细胞膜与细胞壁部分分离.水浮莲细... 详细信息

利用透射电镜研究了阴离子型表面活性剂LAS和非离子型表面活性剂ae对水生植物水绵、水浮莲的损伤作用.观察发现,在LAS处理液中,水绵细胞壁外层被溶解而消失,载色体的规则螺旋缠绕结构被打乱,集结成团.细胞膜与细胞壁部分分离.水浮莲细胞出现质壁分离,细胞膜部分解体,细胞质中有许多空腔,液泡增大,叶绿体变形;在ae处理液中,水绵细胞壁外层被溶解,细胞膜消失,载色体和造粉核解体,分散于整个由细胞壁内层构成的空腔中.水浮莲细胞膜部分解体,染色质浓缩,核膜逐渐解体,叶绿体和线粒体解体,液泡消失,被细胞质充填.可以推断:LAS和ae对水生植物损伤的机理不同,ae以溶解为主,LAS则除溶解外,所带电荷引起蛋白质构象改变也是主要因素之一.

关键词：表面活性剂水绵水浮莲污染亚显微结构 LAS ae 水生植物损伤显微结构水质监测

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STFT在ae信号特征提取中的应用

仪器仪表学报 2008年第9期29卷 1862-1867页

作者：廖传军李学军刘德顺湖南科技大学机械设备健康维护湖南省重点实验室湘潭411201

机械故障或损伤引发的声发射信号南高频突发脉冲信号和长周期准平稳噪声信号组成,适宜用短时傅里叶变换(STFT)描述其时频特征。本文通过分析典型ae信号及其特征提取,首次将STFT引入声发射故障诊断领域,并提出了ae信号的STFT分析法。通... 详细信息

机械故障或损伤引发的声发射信号南高频突发脉冲信号和长周期准平稳噪声信号组成,适宜用短时傅里叶变换(STFT)描述其时频特征。本文通过分析典型ae信号及其特征提取,首次将STFT引入声发射故障诊断领域,并提出了ae信号的STFT分析法。通过理论分析和仿真,确定了ae信号STFT的理想窗函数及其参数选择,有效地克服了STFT只用一个固定窗分析多尺度信号的缺陷。将STFT用于声发射检测的滚动轴承损伤类型及部件的识别,诊断结果十分准确、清晰和直观。仿真分析和实验研究均表明了STFT能有效提取ae信号的特征,为ae信号的波形分析开辟了一条有效的途径。

关键词： ae STFT 特征提取窗函数故障诊断轴承

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基于ae时间序列的岩爆预测模型

岩土力学 2009年第5期30卷 1436-1440页

作者：彭琦张茹谢和平曲宏略龙盎四川大学水利水电学院成都610065 中国长江三峡工程开发总公司湖北宜昌443002

根据现场岩爆监测中声发射(ae)时间序列的特点,采用小波神经网络与突变理论,建立了一种新的岩爆预测模型。该模型首先针对监测到的声发射建立小波神经网络模型,对声发射时间序列进行了拟合与预测;再运用突变理论对预测的声发射建立了岩... 详细信息

根据现场岩爆监测中声发射(ae)时间序列的特点,采用小波神经网络与突变理论,建立了一种新的岩爆预测模型。该模型首先针对监测到的声发射建立小波神经网络模型,对声发射时间序列进行了拟合与预测;再运用突变理论对预测的声发射建立了岩爆突变预测模型。通过实例分析表明,声发射的预测精度较高,岩爆预测结果与现场情况一致,证明了该模型工程实用性较强。

关键词：岩爆 ae 小波神经网络突变理论预测模型

双频激励耦合PDE-ae射频系统的准周期稳态响应模拟算法研究

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电子学报 2003年第12期31卷 1856-1860页

作者：武新宇来金梅孙承绶任俊彦章倩苓复旦大学专用集成电路与系统国家重点实验室上海200433

本文结合谐波平衡思想 ,提出在空间上离散MOSFET偏微分方程 ,建立与之相应的混合型多变量谐波平衡方程 ,扩展了谐波平衡方程的应用范围 .为了有效地完成这种复杂混合型多变量谐波平衡方程的求解 ,运用谐波平衡方程的同解变换、初始值预... 详细信息

本文结合谐波平衡思想 ,提出在空间上离散MOSFET偏微分方程 ,建立与之相应的混合型多变量谐波平衡方程 ,扩展了谐波平衡方程的应用范围 .为了有效地完成这种复杂混合型多变量谐波平衡方程的求解 ,运用谐波平衡方程的同解变换、初始值预估以及阻尼Newton迭代算法等策略 ,使算法的收敛速度和计算性能都有大幅度提高 .以单平衡混频器为例的模拟结果进一步显示该方法不但能有效地反映出射频电路MOSFET器件的分布特性 ,且算法计算性能对频差变化不灵敏。

关键词：射频集成电路稳态响应双频激励混频器谐波平衡方程 PDE ae

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LAS、ae降解菌的筛选及降解效率的研究

上海环境科学 2002年第12期21卷 725-727页

作者：李学军韦平英胡明成桂林电子工业学院电子工程系桂林541004

以某合成洗涤剂厂曝气池活性污泥为菌种来源,表面活性剂直链烷基苯磺酸钠(LAS)及脂肪醇聚氧乙烯醚(ae)为唯一碳源进行选择培养,从中分离出5株降解LAS、ae能力强的菌株。根据各菌株菌体形态、染色反应和生理生化反应,分别对5菌株进行了... 详细信息

以某合成洗涤剂厂曝气池活性污泥为菌种来源,表面活性剂直链烷基苯磺酸钠(LAS)及脂肪醇聚氧乙烯醚(ae)为唯一碳源进行选择培养,从中分离出5株降解LAS、ae能力强的菌株。根据各菌株菌体形态、染色反应和生理生化反应,分别对5菌株进行了菌种鉴定,并在不同的温度、pH值和供氧的情况下对5株菌株进行培养,确定菌株生长所适宜的环境条件。同时根据LAS、ae对水绵伤害实验,以生物监测的方法对菌株降解LAS、ae的效率进行了研究。

关键词： LAS ae 降解效率直链烷基苯磺酸钠脂肪醇聚氧乙烯醚生物降解菌株筛选合成洗涤剂工业废水处理