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81.
Isothermal nucleic-acid amplification methods such as Loop-Mediated isothermal AMPlification (LAMP) are increasingly appealing alternatives to PCR for use in portable diagnostic system due to the low cost, weight, and power requirements of the instrumentation. As such, interest in developing new probes and other functionality based on the LAMP reaction has been intense. Here, we report on the development of duplexed LAMP assays for pathogen detection using spectrally unique Assimilating Probes. As proof of principle, we used a reaction for Salmonella enterica as a model coupled with a reaction for λ-phage DNA as an internal control, as well as a duplexed assay to sub-type specific quarantine strains of the bacterial wilt pathogen Ralstonia solanacearum. Detection limits for bacterial DNA analyzed in individual reactions was less than 100 genomic equivalents in all cases, and increased by one to two orders of magnitude when reactions were coupled in duplexed formats. Even so, due to the more robust activity of newly available strand-displacing polymerases, the duplexed assays reported here were more powerful than analogous individual reactions reported only a few years ago, and represent a significant advance for incorporation of internal controls to validate assay results in the field.  相似文献   
82.
Harmonic elimination pulse width modulation (HEPWM) method has been widely applied to multilevel voltage source inverter (MVSI) to remove low frequency harmonics from its output voltage. However, the computation of the HEPWM switching angles for MVSI is very challenging due to several constraints, namely angle sequencing, very tight angular spacing and the numerous possibilities of angles distribution ratio. Realizing the potential of Differential Evolution (DE) to handle complex problems, this work proposes its application to solve the HEPWM problem for cascaded MVSI. Its emphasis is on improving the availability of HEPWM for higher output voltage by extending the maximum range of modulation index (M). It also removes the discontinuities in the switching angles and reduces the number of distribution ratio required to obtain the required solution. Compared to the most advanced (similar) work, i.e., 7-level MVSI with seventeen switching angles, DE covers a wider range of M; the maximum achievable M is 2.80. Furthermore, it exhibits very low second order distortion factor (DF2): for the worst case, the value of DF2 is 0.0014%. To verify the viability of the proposed algorithm, simulation is carried out and hardware prototype is constructed. Both results show very good agreement with the theoretical prediction.  相似文献   
83.
大庆油田的开发逐渐进入高含水阶段,厚油层动用程度低,"二三结合"开发模式是有效的提高厚油层动用程度,改善水驱开发效果,提高油田采收率的有效手段。在"二三结合"开发模式注聚阶段中注采比对井间压力、含水饱和度等变化有重要影响。为了探究注采比对开发层位的井间压力及饱和度的影响,利用油藏数值模拟方法,模拟了相同的开发模式不同注采比的生产情况,绘制了不同注采比情况下,不同层位的井间压力及含水饱和度变化情况,为维持地层压力平衡,保持油田稳定生产提供有力的依据。  相似文献   
84.
Measuring nonlinear optical response of a specific material in a mixture, not only leads to investigate the behavior of a particular component in various circumstances, but also can be a way to select suitable combination and optimum concentration of additives and therefore obtaining the maximum nonlinear optical signals. In this work, by using dual-arm Z-scan technique, the nonlinear refractive index of Disperse Red1 (DR1) organic dye molecules inside the core of prepared polymeric nanocapsules was measured among various materials which prepared nanocapsules were made of them. Then the measured value was compared with nonlinear refractive index of DR1 solved in dichloromethane.  相似文献   
85.
针对目前量子私有信息检索不能适用与云存储的多数据库问题,基于现在成熟的量子密钥分发方法,提出了一种适合在多数据库环境下,实用的量子私有信息检索协议。对于不同大小的数据库,协议可通过调节参数θ和k,在保证数据库安全及用户隐私的情况下,完成信息的检索。性能分析结果表明,协议的通信复杂度低,检索成功率高、易于实施。  相似文献   
86.
曾秋云 《电子科技》2015,28(4):116-119
基于传统AI-EBG结构,提出了一种小尺寸的增强型电磁带隙结构,实现了从0.5~9.4 GHz的宽频带-40 dB噪声抑制深度,且下截止频率减少到数百MHz,可有效抑制多层PCB板间地弹噪声。文中同时研究了EBG结构在高速电路应用时的信号完整性问题,使用差分信号方案可改善信号完整性。  相似文献   
87.
丁小波 《电子科技》2015,28(4):142-145
介绍了一种基于高性能浮点DSP芯片TMS320C32、CPLD芯片XC95288和A/D采样芯片AD976组成的多路采集系统的工作原理以及设计方法。通过对第一路施加特殊的电压量,在CCS开发环境下读取采样缓冲区的值,并利用Matlab对采样数据进行了全波傅氏变换。此外,该系统已在继电保护中得到广泛应用,实践表明,该系统能较好地解决多路模拟量的采集,并确保了采样数据的安全可靠性。  相似文献   
88.
高强不锈钢绞线网与ECC的黏结是二者协同工作的基础,且黏结 滑移关系模型是其黏结性能的综合反映,故通过对17组51个高强不锈钢绞网增强ECC薄板试件进行单边拉拔试验,研究横向钢绞线间距、纵向钢绞线直径和相对锚固长度等因素对钢绞线网在ECC中黏结性能的影响规律。试验结果表明,横向钢绞线的设置可使黏结破坏由脆性破坏转变为延性破坏;高强不锈钢绞线网与ECC的黏结滑移曲线可分为5个阶段,分别为上升段、微降段、延性强化段、下降段和残余段。基于试验结果,对钢绞线网在ECC中的黏结破坏特征和黏结 滑移机理进行分析,在相关黏结-滑移关系模型的基础上,提出钢绞线网与ECC的黏结 滑移关系模型,并进行模型参数分析。所提模型及模型参数计算公式与试验结果吻合良好,能较好地反映钢绞线网与ECC的界面黏结滑移特征。  相似文献   
89.
In the early design stage, automotive modeling should both meet the requirements of aesthetics and engineering. Therefore, a vehicle CAD (computer aided design) model that can be easily adjusted by feedbacks is necessary. Based on CE-Bézier surface, this paper presents a set of algorithms for parametric segmentation and fairing surface generation in a car model. This model is defined by a simplified automotive template and relevant control points, shape parameters and segmentation parameters, which can be modified to alter the car form efficiently. With this model and the corresponding adjustment method, more than fifty various vehicle models are established in this research according to different parameters. And two methods for calculating similarity index between car models are constructed, which are suitable for brand design trend analysis and modelling design decisionmaking.  相似文献   
90.
From the perspectives of scientific researches and practical applications, it is desirable to explore high operating temperature ferromagnetic films. The effect of biaxial strain on magnetic properties of (110)-oriented La0.7Sr0.3MnO3 films was studied. High quality La0.7Sr0.3MnO3 films were grown on (110)-oriented perovskite single crystal substrates using pulsed laser deposition, varying substrate-induced misfit strains from ??2.27–0.75%. A remarkable enhancement of Curie temperature has been achieved for (110)-oriented La0.7Sr0.3MnO3 films clamped with small misfit strains (i.e., grown on LAST (110)). The enhanced Curie temperature of (110)-oriented La0.7Sr0.3MnO3 films could be attributed to the misfit strain between the films and the underlying substrates and may have technological implication for applications at high temperature environments.  相似文献   
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