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排序方式: 共有134条查询结果,搜索用时 15 毫秒
1.
纪越峰  冯建和  徐大雄 《光子学报》2003,32(9):1094-1097
研究了光分插复用器(OADM)的关键技术,重点分析了相关的实现技术,完成了利用OADM构建全光环网的实验研究,给出了重要的实验数据,包括眼图、光谱图、光信噪比、保护与恢复等,并对这些实验数据进行了分析,为光传送网的设计与构建提供了重要的参考依据.  相似文献   
2.
In this paper, novel interleavers using circular cavities (CC) in a Mach-Zehnder interferometer (MZI) has been presented and demonstrated for the first time, in which CCs act as phase dispersive mirrors which exhibit a periodic dependence on the frequency of light. Three implementation schemes have been proposed and investigated. Theoretical analysis shows the spectral characteristics of each scheme in a 50-GHz channel spacing application. Furthermore, the chromatic dispersion (CD) of each output comb can be flattened within passband by appending an additional CC. The result shows that the proposed designs with novel interferometer technique can simultaneously provide flat top passbands, high isolation stopband and low CD value as well.  相似文献   
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4.
One rapid CE method was established to diagnose Duchenne muscular dystrophy (DMD). DMD is a severe recessive inherited disorder frequently caused by gene deletions. Among them, exons 1–20 account for nearly 30% of occurrences. In this study, the universal multiplex PCR was used to enhance the fluorescently labeling efficiency, which was performed only by one universal fluorescent primer. After PCR, a short‐end injection CE (short‐end CE) speeded up the genotyping of the DMD gene. This method involved no extra purification, and was completed within 9 min. The CE conditions contained a polymer solution of 1.5% hydroxylethylcellulose in 1× TBE buffer at 6 kV for separation. This method was applied to test six DMD patients and one healthy male person. The results showed good agreement with those of multiplex ligation‐dependent probe amplification. This method can be applied for clinical diagnosis of DMD disease. Accurate diagnosis of the DMD gene is the best way to prevent the disease.  相似文献   
5.
Antibody‐conjugated magnetic nanoparticles (Ab‐MNPs) have potential in pathogen detection because they allow target cells to be easily separated from complex sample matrices. However, the sensitivity and specificity of pathogen capture by Ab‐MNPs generally vary according to the types of MNPs, antibodies, and sample matrices, as well as preparation methods, including immobilization. Therefore, achieving a reproducible analysis utilizing Ab‐MNPs as a pathogen detection method requires accurate characterization of Ab‐MNP capture ability and standardization of all handling processes. In this study, we used high‐resolution CE‐single strand conformational polymorphism coupled with a stuffer‐free multiplex ligation‐dependent probe amplification system to characterize Ab‐MNPs. The capture ability of Ab‐MNPs targeting Salmonella enteritidis and nine pathogens, including S. enteritidis, was analyzed in phosphate buffer and milk. The effect of storage conditions on the stability of Ab‐MNPs was also assessed. The results showed that the stuffer‐free multiplex ligation‐dependent probe amplification system has the potential to serve as a standard characterization method for Ab‐MNPs. Moreover, the precise characterization of Ab‐MNPs facilitated robust pathogen detection in various applications.  相似文献   
6.
毛红霞  黎源倩  裴晓方  何超  渠凌丽 《色谱》2007,25(4):473-477
建立了食品中常见致病菌大肠杆菌O157:H7的uidA基因、沙门菌的invA基因和志贺菌的ipaH基因的多重聚合酶链反应(PCR)产物的毛细管电泳快速检测方法。根据这3种致病菌的特异性基因序列设计多重PCR引物,优化PCR扩增反应体系,采用7.0 g/L 甲基纤维素为筛分介质,毛细管电泳-激光诱导荧光检测法同时检测了3种常见致病菌的PCR扩增产物。在优化的多重PCR反应和毛细管筛分电泳条件下,该方法可以同时检测沙门菌、志贺菌和大肠杆菌O157:H7基因的多重PCR扩增产物,22 min内即可完成3种常见致病菌的毛细管电泳检测。迁移时间的相对标准偏差为1.47%~2.07%。与凝胶电泳法比较,该法简便快速,灵敏度高,可用于多种致病菌脱氧核糖核酸的检测,为食品安全提供了一种可靠的快速检测方法。  相似文献   
7.
半导体荧光量子点因其独特的一元激发/多元发射、耐光漂白、发射波长可调等光学性质在细胞生物学研究、生物化学传感、药物筛选及示踪、环境监测等诸多领域都得到广泛的应用.本文简述了量子点的基本特性,重点介绍了近年来基于量子点的荧光特性及其与荧光共振能量转移、分子信标、荧光原位杂交等分析技术相结合而发展起来的一些新技术,以及基于QDs的阳极溶出伏安法和电化学发光在多组分分析方面的研究进展,最后就该研究领域现存的问题和将来的发展方向提出了拙见.  相似文献   
8.
张娟  刘立人 《光子学报》2007,36(5):834-837
研究了一种新型模拟双折射结构DWDM滤波器的中心频率和带宽的可调谐特性.研究表明:当给定满足一定平坦化要求的光谱透射率所需的各模拟波片中偏振旋转器的旋转角时,通过模拟波片中楔形介质对的相对位移来调节光在各模拟波片中的光程差,同时保持光程差仍满足特定的比例关系,可实现中心频率及带宽的调谐.当光在各模拟波片中的光程差变化较小时,可实现中心频率的调谐,此时带宽的改变很小,可忽略不计;随着光程差变化的不断增大,带宽的改变则不能忽略.  相似文献   
9.
Standard phase cycled NMR pulse sequences were generalized such that for each individual step of the pulse phase cycle the free induction decay is stored separately without phase correction. This is in contrast to the usual practice, where pulse responses are phase shifted immediately (by applying a ‘receiver phase’) and co‐added as they are stored. The approach used here allows one to extract different types of NMR information, which are usually referred to as different ‘experiments’, from the same raw data set a posteriori by using complex linear combinations. Storing the free induction decays of individual phase cycle steps separately and using specific linear combinations of these data to obtain a particular type of information increase the overall efficiency of a given set of NMR experiments substantially, because all information can be derived from a single multiplexed data set. This ‘super‐experiment’ requires only as much time as the most complex of the derived specific experiments alone. The principle of this multipurpose approach was demonstrated by performing different multiple‐quantum filtered COSY experiments. It also becomes possible to generate linear combinations, which differ from the conventionally acquired spectra a posteriori. For example, we implemented diagonal peak reduction by using zero‐ and single‐quantum filtered COSY contributions without requiring additional experiment time. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
10.
旋转光楔多重全息术   总被引:2,自引:0,他引:2  
胡克莉  吴建南 《光学学报》1992,12(5):35-439
本文提出一种新颖的多重全息术,它是利用旋转光楔调制平面参考波的传播方向,实现编码参考光记录获得多重全息图.该全息图经球面波再现,获得位于同一平面内的再现多重象.文中给出了这种方法的理论分析和实验结果,两者是吻合的.  相似文献   
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