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131.
The multi-stage humidifier semi-dry flue gas cleaning technology, the CRS plasma flue gas cleaning technology and oxidative additive flue gas cleaning technology were investigated for multi-pollutants removal. The semi-dry flue gas cleaning technology using multistage humidifier and additive can improve oxidation and absorption, and it can achieve high multi-pollutants removal efficiency. The CRS discharge can produce many OH radicals that promote NO oxidation. Combining NaOH absorption can achieve high deSO2 and deNOx efficiencies. It is very fit of the reconstruction of primary wet flue gas desulfurization (WFGD). In addition, Using NaClO2 as additive in the absorbent of WFGD can obtain very high removal efficiency of SO2 and NOx. 相似文献
132.
Direct numerical simulation is employed to investigate the premixed jet flame of methane in lean, combined with a detailed chemical kinetics including 17 species and 58 elemental steps and distinct Lewis numbers. Cold methane-air mixture at 0.55 equivalence ratio is injected into the coflow area with 9500 Reynolds number. The coflow ambient gas is set to be the burnt gas of the methane-air mixture in main jet and temperature is assigned to be the corresponding adiabatic flame temperature 1515 K. The whole s... 相似文献
133.
很多现实的复杂网络都具有无标度特性,其节点度具有幂律分布的规律。主要讨论幂指数γ<2的无标度网络的性质,指出当γ<2时,网络中最小度的节点数以及网络的平均度都与网络大小N有某种数量关系。通过与γ≥2的无标度网络对比,该类特殊网络呈现出不同的性质和行为,网络的边与节点相比呈现快速增长,具有更大的平均度,网络中有更多的边,网络不再稀疏。 相似文献
134.
The numerical modelling of alkali metal reacting dynamics in turbulent pulverised-coal combustion is discussed using tabulated sodium chemistry in large eddy simulation (LES). A lookup table is constructed from a detailed sodium chemistry mechanism including five sodium species, i.e. Na, NaO, NaO2, NaOH and Na2O2H2, and 24 elementary reactions. This sodium chemistry table contains four coordinates, i.e. the equivalence ratio, the mass fraction of the sodium element, the gas-phase temperature, and a progress variable. The table is first validated against the detailed sodium chemistry mechanism by zero-dimensional simulations. Then, LES of a turbulent pulverised-coal jet flame is performed and major coal-flame parameters compared against experiments. The chemical percolation devolatilisation (CPD) model and the partially stirred reactor (PaSR) model are employed to predict coal pyrolysis and gas-phase combustion, respectively. The response of the five sodium species in the pulverised-coal jet flame is subsequently examined. Finally, a systematic global sensitivity analysis of the sodium lookup table is performed and the accuracy of the proposed tabulated sodium chemistry approach has been calibrated. 相似文献
135.
We perform a global effective-field-theory analysis to assess the combined precision of Higgs couplings,triple gauge-boson couplings, and top-quark couplings, at future circular e~+e~- colliders, with a focus on runs below the tt production threshold. Deviations in the top-quark sector entering as one-loop corrections are consistently taken into account in the Higgs and diboson processes. We find that future lepton colliders running at center-of-mass energies below the tt production threshold can still provide useful information on top-quark couplings, by measuring virtual top-quark effects. With rate and differential measurements, the indirect individual sensitivity achievable is better than at the high-luminosity LHC. However, strong correlations between the extracted top-quark and Higgs couplings are also present and lead to much weaker global constraints on top-quark couplings. This implies that a direct probe of top-quark couplings above the tt production threshold is also helpful for the determination of Higgs and triple-gauge-boson couplings. In addition, we find that below the e~+e~-→tth production threshold, the top-quark Yukawa coupling can be determined by its loop corrections to all Higgs production and decay channels. Degeneracy with the ggh coupling can be resolved, and even a global limit is competitive with the prospects of a linear collider above the threshold. This provides an additional means of determining the top-quark Yukawa coupling indirectly at lepton colliders. 相似文献
136.
骨组织受力变形后其内部液体就会流动,同时在其微观结构——骨单元壁中扩散,并进一步产生一系列与骨液流动相关的物理效应,如流体剪切应力、流动电位等,这些物理效应被细胞感知并做出破骨或成骨等反应,来使骨适应外部载荷环境.鉴于骨组织产生的内部液体流动很难实验测定,理论模拟是目前的主要研究手段.基于骨单元的多孔弹性性质建立了骨小管内部液体的流动模型,该模型将骨单元所受的外部载荷与骨小管内部液体的压力、流速、流量和切应力联系起来,并进一步可以研究其力传导与力电传导机制.骨小管模型的建立分别基于中空和考虑哈弗液体的骨单元模型,并考虑了骨单元外壁的弹性约束和刚性位移约束两种边界条件.最终得到骨单元在外部轴向载荷作用下,骨小管内部液体的流量及流体切应力的解析解.结果表明:骨小管中的液体流量与流体切应力都正比于应变载荷幅值和频率,并由载荷的应变率决定.因此应变率可以作为控制流量和流体切应力的一种生理载荷因素.流量随着骨小管半径的增大而非线性增大,而流体切应力则随着骨小管半径的增大而线性增大.此外,在相同的载荷下,含哈弗液体的骨单元的模型中,骨小管中液体的流量和切应力均大于中空骨单元模型. 相似文献
137.
基于无机元素分析对地理标志五常大米鉴别技术的研究 总被引:2,自引:0,他引:2
五常大米是我国著名地理标志产品之一,品质高、产量低,导致制假售假的现象严重。为维护五常大米的品牌形象和消费者利益,急需一种有效鉴别五常大米的方法。应用电感耦合等离子体光谱及电感耦合等离子体质谱测定大米中无机元素含量,结合主成分分析(PCA)、Fisher判别、人工神经网络(ANN)对五常大米鉴别模型进行研究。结果表明:PCA法对样品的分类效果较差,采用Fisher判别和ANN则可准确识别五常地区的大米样品和其他地区的大米样品。Fisher判别法对校正集和验证集样品平均准确识别率分别为93.5%,而ANN法对同样的校正集和验证集样品的平均准确识别率为96.4%,优于Fisher判别法。可准确对五常大米进行鉴别,为该产品的地理标志保护提供了一种技术手段。 相似文献
138.
陈岑 《科技情报开发与经济》2013,23(14):74-76
高校图书馆的流通工作对于图书馆的价值体现具有十分重要的作用。对高校图书馆流通工作的现状进行了分析,有针对性地提出一些优化高校图书馆流通工作的对策。 相似文献
139.
XiaoGang Wu YanQin Wang XiaoHong Wu HaiPeng Cen Yuan Guo WeiYi Chen 《中国科学:物理学 力学 天文学(英文版)》2014,57(11):2161-2167
It has been suggested that microcracks do play a key role in the triggering of the bone remodeling process. In order to evaluate the influence of microcracks on the poroelastic behaviors of an osteon, a finite element model is established and investigated by using the Comsol Multiphysics software. The findings show that the presence of a microcrack in the osteon wall strongly modifies (enlarges) its local fluid pressure and velocity. Especially, the pressure and velocity amplitudes produced in the microcracked region are larger than those of the non-cracked region. Thus, this study can also be used for proposing a likely mechanism that bone can sense the changes of surrounding mechanical environments. 相似文献
140.
给定n个非负基本随机变量,其分布属于一致变化重尾分布族,以及另外n个非负任意相依的加权随机变量,但是与基本随机变量相互独立,在一类相依结构下,本文得到了基本随机变量和与加权随机变量和条件分布尾若干渐近公式,并给出了它们在风险度量中的一个应用,推广了相关文献的结论。 相似文献