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811.
812.
As well known, if the Higgs boson were not observed at LHC, the technicolor model would be the most favorable candidate responsible for the symmetry breaking. To overcome some defects in the previous model, some extended versions have been proposed. In the TC2 model typical signature is existence of heavy HTC and technipion Π. A direct proof of validity of the model is to produce them at accelerator. Thus we study the production rates of e+ e- → HTCΠ0 and e+ e- → Π+ Π- at ILC in the topcolor-assisted technicolor (TC2) model. In fact, there is a flood of models belonging to new physics, which can result in products withcharacteristics similar to HTC+Π of the TC2 model. Therefore to distinguish this model from others one may need to investigate some details by calculating the cross section to NLO. We indeed find that the NLO corrections are significant, namely the ratio δ ≡ (σNLO- σLO)/σLO in e+ e- → HTC Π0 exceeds 100% within a plausible parameter space. 相似文献
813.
814.
应用微扰展开法了“跳跃模型”给出了空间电荷场前三阶分量随时间,外加电场等变化的解析表达式,同时讨论了外加电场对各阶空间电荷场建立的影响,当扩散与外加电场可比拟时,外加电场对空间电荷场的影响不大,随着空间电荷场阶数的提高,其达到最大饱和值所需的外加电磁越小,在外加电场作用下,空间电荷场各阶分量随时间呈振荡衰减,直到达到饱和,外加是场越大,振荡越强烈,周期越短,在考虑高阶分量的贡献后,空间电荷场的振荡 相似文献
815.
We propose a criterion for the separability of quantum pure states using the concept of a partial Hermitian conjugate. It is equivalent to the usual positive partial transposition criteria, with a simple physical interpretation. 相似文献
816.
Power grids have been studied as a typical example of real-world complex networks. Different from previous methods, this paper proposes a hybrid approach for structural vulnerability analysis of power transmission networks, in which a DC power flow model with hidden failures is embedded into the traditional error and attack tolerance methodology to form a new scheme for power grids vulnerability assessment and modeling. The new approach embodies some important characteristics of power transmission networks. Furthermore, the simulation on the standard IEEE 118 bus system demonstrates that a critical region might exist and when the power grid operates in the region, it is vulnerable to both random and intentional attacks. Finally, a brief theoretical analysis is presented to explain the new phenomena. 相似文献
817.
根据X射线衍射图谱对铈掺杂的钆镓铝石榴石相玻璃陶瓷的晶体结构进行分析,采用直径10英寸积分球结合CCD(charge coupled device)探测器系统,对蓝色半导体发光二极管激发下铈掺杂钆镓铝石榴石相玻璃陶瓷的荧光光谱进行测试,解析出样品发光的绝对光谱功率分布,推导出光量子数分布,求得荧光量子产率和组合白光的色坐标及其相关色温。结果表明,所调查的铈掺杂钆镓铝石榴石相玻璃陶瓷在蓝光LED激发下的荧光量子产率为29.2%,所获得组合白光的色坐标x=0.319,y=0.349,相关色温为6 086K。尽管该混晶陶瓷的荧光量子产率稍小于铈掺杂YAG玻璃陶瓷,但其与蓝光LED组合后发光的色温也明显低于后者,从而为舒适型LED照明玻璃陶瓷的进一步优化提供了新思路。 相似文献
818.
SE-HPLC/ICP-MS/ESI-MS联用技术用于富镉植物中镉的形态研究 总被引:4,自引:0,他引:4
用不同形态的镉培养液(氯化镉、硝酸镉、镉-EDTA、草酸镉和柠檬酸镉)对不同种类的蕨类植物(狗脊、舌厥、石松、瓦韦和石韦)进行培养。研究发现,镉在植物体不同部位的富集量是有差异的(富集量:根>茎>叶);对SEC-HPLC截取出的植物鳌合肽(PCs)研究表明,不同形态的镉能不同程度的诱发植物体中PCs的合成,从而PCs与Cd配位,降低镉的毒性,发现的配体主要为PC3,iso-PC3(βAla)和iso-PC2(βAla)。文章还研究了不同形态镉胁迫下的蕨类植物各部位中镉的分布情况,并且对植物体中经镉诱导形成的PCs-Cd配合物的形态进行研究,进而对其解毒机理进行探讨。 相似文献
819.
ZHANG Hua FENG Dazheng PANG Jiyong 《声学学报:英文版》2010,29(1):45-55
A blind speech source separation method for the overdetermined convolutive mixture model in time-domain is proposed via joint block-diagonalization based on the mutual- independence and short-time stationarity properties of the speech signals. Taking the sum of the F-norms of all off-diagonal sub-matrices as a criterion, a novel joint block-diagonalization method is proposed to estimate the whole mixture matrix through minimizing a sequence of quadratic sub-functions corresponding to mixture sub-matrices. Both theoretical analysis and simulations show that the proposed method has much lower complexity and faster convergence speed than the classical Jacobi-like method with no performance loss. In addition, there are almost no obvious impacts of the channel order and initialization values on the convergence speed. 相似文献
820.
The interaction of an atmospheric pressure plasma jet using argon or argon plus hydrogen peroxide vapour addition with bacillus subtilis 下载免费PDF全文
This paper reports that an atmospheric pressure dielectric barrier discharge plasma jet, which uses argon or argon + hydrogen peroxide vapour as the working gas, is designed to sterilize the bacillus subtilis. Compared with the pure argon plasma, the bacterial inactivation efficacy has a significant improvement when hydrogen peroxide vapour is added into the plasma jet. In order to determine which factors play the main role in inactivation, several methods are used, such as determination of optical emission spectra, high temperature dry air treatment, protein leakage quantification, and scanning electron microscope. These results indicate that the possible inactivation mechanisms are the synergistic actions of chemically active species and charged species. 相似文献