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左氧氟沙星铜(II)配合物的合成及生物活性研究
合成了四个新左氧氟沙星铜(II)配合物:[Cu(Lvfx)(Bipy)(H2O)]Cl·4H2O(1),[Cu(Lvfx)(Phen)(H2O)]Cl·5H2O(2),[Cu(Lvfx)(Tatp)(H2O)]Cl·5H2O(3),[Cu(Lvfx)(Dppz)(H2O)]Cl·4.5H2O(4){Lvfx=左氧氟沙星,Bipy:2,2'-联吡啶,Phen=1,10-邻菲罗啉,Tatp=1,4,8,9-四氮三联苯,Dppz=二吡啶并[3,2-a:2',3'-c]吩嗪},并通过红外光谱法、紫外-可见光谱法、元素分析、原子吸收光谱法、摩尔电导率分析和差热.热重分析对配合物进行了表征.用滤纸片扩散法和试管二倍稀释法分别测试了配合物及配体对大肠杆菌、金黄色葡萄球菌的抗菌活性,结果显示配合物(3)对大肠杆菌具有最佳的抑菌效果.采用荧光光谱法初步研究了配合物与BSA的相互作用.结果表明,四个配合物均对BSA的荧光有较强的猝灭作用,且发生了能量转移,其与BSA的结合常数(K)分别为4.7*103、5.7*103、5.0*103和1.7*103L·mol-1,结合位点n分别为0.59、0.83、0.81和0.69.邓素文,胡伟,林若琳,钟美,陈冬贵,熊亚红,刘小平 - 化学研究与应用文章来源: 万方数据 -
The existing research of steering efficiency mainly focuses on the mechanism efficiency of steering system,aiming at designing and optimizing the mechanism of steering system.In the development of assist steering system especially the evaluation of its comfort,the steering efficiency of driver physiological output usually are not considered,because this physiological output is difficult to measure or to estimate,and the objective evaluation of steering comfort therefore cannot be conducted with movement efficiency perspective.In order to take a further step to the objective evaluation of steering comfort,an estimating method for the steering efficiency of the driver was developed based on the research of the relationship between the steering force and muscle activity.First,the steering forces in the steering wheel plane and the electromyography(EMG)signals of the primary muscles were measured.These primary muscles are the muscles in shoulder and upper arm which mainly produced the steering torque,and their functions in steering maneuver were identified previously.Next,based on the multiple regressions of the steering force and EMG signals,both the effective steering force and the total force capacity of driver in steering maneuver were calculated.Finally,the steering efficiency of driver was estimated by means of the estimated effective force and the total force capacity,which represented the information of driver physiological output of the primary muscles.This research develops a novel estimating method for driver steering efficiency of driver physiological output,including the estimation of both steering force and the force capacity of primary muscles with EMG signals,and will benefit to evaluate the steering comfort with an objective perspective.- 中国机械工程学报文章来源: 万方数据
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大型会展活动中的事件分析研究
以大型会展活动中产生的互联网新闻报道为研究对象,重点阐述如何及时、准确地识别出特定应用场景下的系列事件和把握事件爆发前后的地域空间分布状态,然后结合领域知识和内容分析、信号分析等方法对这些信息进行合理解读,从而完成相关情报分析活动.许鑫,姚占雷,郭金龙 - 图书情报工作文章来源: 万方数据 -
柳珊瑚及其共生微生物活性代谢产物的研究进展
柳珊瑚中含有许多结构新颖、生物活性多种多样的次生代谢产物,引起了人们对其化学成分及药理活性研究的极大兴趣.共生菌是长期与宿主共同生活的一大类群的特殊微生物,因长期与宿主共进化,其生理生化特点更加鲜明、次生代谢产物合成更具特色.近几年,柳珊瑚共生微生物活性代谢产物的研究越来越多地受到人们的关注.本文综述了2000年至2010年间有关柳珊瑚及其共生微生物中化学成分及生物活性研究的进展,并在此基础上对柳珊瑚共生微生物潜在的药用前景进行了展望.温露,韦啟球,蔡隽妮,陈钢,张世倡 - 中国抗生素杂志文章来源: 万方数据 -
多晶体航空γ能谱仪的地面辐射监测模拟仿真
采用基于MCNP5的Monte Carlo模拟方法对多晶体航空γ能谱仪用于地面辐射监测进行模拟仿真.鉴于目前航空γ能谱仪主要用于资源勘探,对137Cs以及131I低能射线探测并不关注.本文以地面辐射为监测目标,通过建立多晶体航空γ能谱仪探测装置的Monte Carlo模拟模型,获得137Cs以及131I的模拟电子脉冲能量幅度分布谱,然后用计算得到的全能峰高斯展宽系数对模拟电子脉冲能量幅度分布谱进行高斯展宽,并对不同探测条件下最小可探测活度(Minimum detectable activity,MDA)进行计算.结果表明,Monte Carlo模拟方法能较好地对地面辐射监测进行仿真,在相同测量条件下,探测器外置计数比探测器内置计数大,且探测器外置时MDA优于探测器内置时MDA.所以实际航测过程中,建议采用探测器外置的方式,以减小MDA值.龚春慧,曾国强,葛良全,汤晓斌,谭承君 - 核技术文章来源: 万方数据 -
链霉菌108A1776产生的水溶性链丝菌素
目的分离纯化链霉菌108A1776发酵液中的水溶性抗耐药结核活性成分.方法利用离子交换、反相和亲水作用等多种色谱技术进行分离纯化,通过现代波谱学方法鉴定活性成分结构.结果分离得到3个水溶性活性成分,其结构分别确定为链丝菌素EO)、N^β-乙酰链丝菌素E(2)和β-乙酰链丝菌素D(3).链丝菌素E(1)对结核分枝杆菌H37Rv和临床分离耐药株的MIC值为0.25~1.0μg/mL.结论首次利用亲水作用色谱分离纯化微生物发酵液中的水溶性活性化合物.亲水作用色谱在微生物水溶性次级代谢产物的分离纯化中具有广阔的应用前景.链丝菌素E具有较强的体外抗耐药结核分枝杆菌活性.甘茂罗,郑旭东,关艳,刘玉凤,郝雪秦,肖春玲 - 中国抗生素杂志文章来源: 万方数据

