火焰辐射及偶丝导热对热电偶测温影响的数值分析

本文利用层流同向扩散乙烯火焰的数值模拟结果,根据所得的火焰温度场、气体速度场、火焰辐射场,分析火焰辐射、热电偶偶丝导热对热电偶测温的影响.结果表明在火焰的低温区火焰辐射要大于节点向外辐射,节点得到的能量要高于节点损失的能量,因此在火焰的低温区节点温度要高于当地的气体温度;同时直径为100μm的热电偶存在较大的导热,对节点温度测量有较大的影响.     

Bayesian Approach to Retrieving a Vertical Ozone Profile from Radiometric Measurement Data

We propose a technique for retrieving a vertical profile of the atmospheric ozone number density from ground-based radiometry data. The technique is based on the Bayesian approach to solving inverse problems and permits one, by allowing for measurement noise and using certain a priori information on the retrieved profile, to construct the probability distribution of the ozone number density in the entire altitude range being monitored. Using the proposed technique, we compare the retrieval results obtained for various (both well-known and suggested for the first time in this paper) methods of approximation and regularization of retrieved profiles. Model examples demonstrate that the proposed technique is capable of retrieving ozone-profile disturbances which accompany the formation of ozone holes.     

Understanding Symmetric and Asymmetric DNA Patterns by Water Flow on a Solid Surface

In order to use DNA for making molecular device, specific DNA patterns on a solid surface should be constructed. In this paper, we will show that the random interactions between the DNA segments and the solid surface play an important role in the final symmetric and asymmetric DNA patterns obtained by water flow.     

The Influence of the Renormalization Condition to the Equation of State of the Nuclear Matter

In the relativistic σ-ω model, the influences of the parameters b, c, d in the potential U(σ)=(1/2!)bσ²+(1/3!)cσ³+ (1/4!)dσ⁴ to the incompressibility, effective mass and binding energy of the nuclear matter are studied in detail. The calculation of equation of state of nuclear matter shows that the values of b, c, d depend on the renormalization condition, we also find that a soft equation of state of nuclear matter can be obtained in a suitable renormalization condition, and the experimental incompressibility coefficient can be reproduced. These results are also used to study the thermal properties of hot Δ-resonant nuclear matter.     

脱粘缺陷对粘接结构频散特性的影响

采用全局矩阵理论,通过引入内聚强度弱化模型和弹簧模型,计算了脱粘缺陷对粘接结构频散特性的影响。分析了内聚强度缺陷、界面缺陷及混合缺陷等因素对粘接结构频散特性的影响,发现频散曲线的演化规律与材料声学性质密切相关。不同材料和不同组合,其规律有很大不同。针对各向同性粘接结构,可能通过考察特定频率段内频散模态的变化,实现对脱粘缺陷的检测。     

Quantum Anti-Zeno Effect in Artificial Quantum Systems

In this paper, we study a quantum anti-Zeno effect （QAZE） purely induced by repetitive measurements for an artificial atom interacting with a structured bath. This bath can be artificially realized with coupled resonators in one dimension and possesses photonic band structure like Bloeh electron in a periodic potential. In the presence of repetitive measurements, the pure QAZE is discovered as the observable decay is not negligible even for the atomic energy level spacing outside of the energy band of the artificial bath. If there were no measurements, the decay would not happen outside of the band. In this sense, the enhanced decay is completely induced by measurements through the relaxation channels provided by the bath. Besides, we also discuss the controversial golden rule decay rates originated from the van Hove＇s singularities and the effects of the counter-rotating terms.     

Trimetallic NiCoM catalysts (M = Mn,Fe, Cu) for methane conversion into synthesis gas

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Influence of the orientation of a crystal on thermal polarization effects in high-power solid-state lasers

The polarization thermal self-action of laser radiation propagating in an isotropic crystal has been studied experimentally. New nonlinear effects have been observed for the first time. These effects include a change in the symmetry of the depolarized-field distribution and the qualitative dependence of the degree of the self-induced depolarization on the geometry of the beam and crystal. The classical problem of self-induced depolarization has been analytically solved in the general form for an arbitrary orientation of any cubic crystal. The theoretical results agree well with the experimental data. The optimum orientation of the laser crystal has been determined, which can be effectively used in lasers with high average power.     

Bethe subalgebras of the group algebra of the symmetric group

We introduce families $ \mathcal{B}_n^S\left( {{z_1},\ldots,{z_n}} \right) $ and $ \mathcal{B}_{{n,\hbar}}^S\left( {{z_1},\ldots,{z_n}} \right) $ of maximal commutative subalgebras, called Bethe subalgebras, of the group algebra $ \mathbb{C}\left[ {\mathfrak{S}n} \right] $ of the symmetric group. Bethe subalgebras are deformations of the Gelfand?Zetlin subalgebra of $ \mathbb{C}\left[ {\mathfrak{S}n} \right] $ . We describe various properties of Bethe subalgebras.