Theoretical Studies on the Kinetics and Mechanisms of Reactions for Methyl Vinyl Ether and Ozone

在甲基乙烯基醚( MVE )的二不同异构体之间的互变现象，从 MVE 的 O 3-initated 反应的主要臭氧化物的形成，在主要臭氧化物之间的转变，和随后的破碎在 BHandHLYP/6 311++G 用量化学药品方法被学习( d ， p )为优化几何学和频率计算并且在 QCISD/6 31G 的理论的水平( d ， p )为单个点精力计算的水平。率系数为温度范围被计算由使用正规转变状态理论(TST ) 的 280 440 K。为 MVE 的臭氧增加，有二不同可能性，为臭氧攻击根据二不同可能的取向讨论。尽管 synperiplanar-MVE 是比 antiperiplanar-MVE 更稳定的 7.11 kJ/mol ，理论学习的结果显示那，因为从臭氧增加 antiperiplanar-MVE 形成的主要臭氧化物是更多的马厩和相应的精力障碍转移状态， antiperiplanar-MVE 在主要臭氧化物的形成起一个更重要的作用更低。在从臭氧增加形成到 antiperiplanar-MVE 的主要臭氧化物之间的互变现象与在另外的主要臭氧化物之间的转变相比是最可存取的。主要臭氧化物的劈开主要导致 CH 2 OO，它与试验性的估计一致。为开始臭氧的反应的计算的全面的率常数是 4.8 × 1 0 −17 在 298.15 K 的厘米 3/(molecules) ，它为乙醇乙烯基醚同意试验性的价值。

Quantum and semiclassical studies on photodetachment cross sections of H^- in a harmonic potential

The photodetachment cross section of H- in a linear harmonic oscillator potential is investigated. This system pro- vides a rare example that can be studied analytically by both quantum and semiclassical methods with some approxi- mations. The formulas of the cross section for different laser polarization directions are explicitly derived by both the traditional quantum approach and closed-orbit theory. In the traditional quantum approach, we calculate the cross sections in coordinate representation and momentum representation, and get the same formulas. We compare the quantum formulas with closed-orbit theory formulas, and find that when the detachment electron energy is larger than hco, where co is the frequency of the oscillator potential, the quantum results are shown to be in good agreement with the semiclassical results.

Finite-size analysis of continuous-variable quantum key distribution with entanglement in the middle

Continuous-variable quantum key distribution(CVQKD) protocols with entanglement in the middle(EM) enable long maximal transmission distances for quantum communications. For the security analysis of the protocols, it is usually assumed that Eve performs collective Gaussian attacks and there is a lack of finite-size analysis of the protocols. However,in this paper we consider the finite-size regime of the EM-based CVQKD protocols by exposing the protocol to collective attacks and coherent attacks. We differentiate between the collective attacks and the coherent attacks while comparing asymptotic key rate and the key rate in the finite-size scenarios. Moreover, both symmetric and asymmetric configurations are collated in a contrastive analysis. As expected, the derived results in the finite-size scenarios are less useful than those acquired in the asymptotic regime. Nevertheless, we find that CVQKD with entanglement in the middle is capable of providing fully secure secret keys taking the finite-size effects into account with transmission distances of more than 30 km.

Quantum calculations for photodetachment cross sections of H^- in an inhomogeneous electric field

We calculate the photodetachment cross sections of H- in a gradient electric field based on traditional quantum approach. The system provides a rare example that the formulas for the cross sections can be explicitly derived by both the quantum approach and closed-orbit theory. The quantum results are compared with those of the closed-orbit theory. The correct phase values in the closed-orbit theory are essential and necessary to produce accurate cross sections. Our quantum results remove some previous ambiguities in assigning the phase values in the closed-orbit theory （G. C. Yang and M. L. Du 2007 Phys. Rev. A 75 029904E）.

Microflow-induced shear stress on biomaterial wall by ultrasound-induced encapsulated microbubble oscillation

A model of an ultrasound-driven encapsulated microbubble（EMB） oscillation near biomaterial wall is presented and used for describing the microflow-induced shear stress on the wall by means of a numerical method. The characteristic of the model lies in the explicit treatment of different types of wall for the EMB responses. The simulation results show that the radius-time change trends obtained by our model are consistent with the existing models and experimental results. In addition, the effect of the elastic wall on the acoustic EMB response is stronger than that of the rigid wall, and the shear stress on the elastic wall is larger than that of the rigid wall. The closer the EMB to the wall, the greater the shear stress on the wall. The substantial shear stress on the wall surface occurs inside a circular zone with a radius about two-thirds of the bubble radius. This paper may be of interest in the study of potential damage mechanisms to the microvessel for drug and gene delivery due to sonoporation.

Classical-field description of Bose-Einstein condensation of parallel light in a nonlinear optical cavity

We study the Bose–Einstein condensation of parallel light in a two-dimensional nonlinear optical cavity,where the massive photons are converted into photon molecules(p-molecules).We extend the classical-field method to provide a description of the two-component system,and we also derive a coupled density equation which can be used to describe the conversion relation between photons and p-molecules.Furthermore,we obtain the chemical potential of the system,and we also find that the system can transform from the mixed photon and p-molecule condensate phase into a pure p-molecule condensate phase.Additionally,we investigate the collective excitation of the system.We also discuss the problem how the spontaneous decay of an atom is influenced by both the phase transition and collective excitation of the coupling system.

Investigation of Linear Tetra-Atomic Negative Ion by Photodetached-Electron Spectra

Photodetachment spectra from a linear tetra-atomic negative ion is investigated by treating the detached-electron wave function quantum mechanically.A plane polarized laser light,perpendicular to the axis of the ion,is used to detach the electron from the ion.Analytical expressions for the electron flux and total photodetachment cross section are derived.The electron flux on screen shows strong-energy-dependent oscillations with different frequencies.The total cross section of the tetra-atomic negative ion reduces the cross section of mono-atomic,diatomic and triatomic negative ions for high energy photons,while for low energy photons it becomes four times the cross section of mono-atomic negative ions.

Photodetachment of a Homo-Nuclear Linear Tetra-Atomic Negative Molecular Ion

The photodetachment of a homo-nuclear linear tetra-atomic negative molecular ion is studied theoretically for an arbitrary laser polarization.An expression for the total cross section is obtained by using an extended version of the two center model,where each center acts as a source of coherent photodetached-electron waves.Strong oscillations on observation plane,placed at a large distance from the ion,are observed.The amplitude of these oscillations is maximum when the laser polarization is parallel to the molecular axis.Furthermore,the amplitude decreases as the angle between the laser polarization and molecular axis increases and consequently vanishes when they are perpendicular to each other.It is also found that if the distance between the adjacent centers is very small or very large,then the ampplitude of oscillations is negligibly small.

Ground state of Rydberg-dressed Bose gas confined in a toroidal trap

The experimental realization of Rydberg dressing technology in ultracold atomic systems provides another superior platform for studying novel states of matter and macroscopic quantum phenomena.In this work,based on the mean-field theory,we have investigated the ground-state phases of a two-component Bose–Einstein condensate with Rydberg interaction and confined in a toroidal trap.The effects of the Rydberg interaction and external potential,especially the Rydberg blockade radius,on the ground-state structure of such a system have been investigated in full parameter space.Our results show that the Rydberg blockade radius,which can be regarded as another controllable parameter,can be used to obtain a variety of ground-state phases.More interestingly,it is found that for weak Rydberg interactions,the Rydberg blockade radius breaks the spontaneous rotational symmetry of the system,leading to the formation of a discrete unit cell structure.For strongly interacting cases,it can be used to realize different orders of discrete rotational symmetry breaking.

Prediction of Protein Structural Classes Using the Theory of Increment of Diversity and Support Vector Machine

Based on the concept of the pseudo amino acid composition （PseAAC）, protein structural classes are predicted by using an approach of increment of diversity combined with support vector machine （ID-SVM）, in which the dipeptide amino acid composition of proteins is used as the source of diversity. Jackknife test shows that total prediction accuracy is 96.6% and higher than that given by other approaches. Besides, the specificity （Sp） and the Matthew＇s correlation coefficient （MCC） are also calculated for each protein structural class, the Sp is more than 88%, the MCC is higher than 92%, and the higher MCC and Sp imply that it is credible to use ID-SVM model predicting protein structural class. The results indicate that： 1 the choice of the source of diversity is reasonable, 2 the predictive performance of IDSVM is excellent, and3 the amino acid sequences of proteins contain information of protein structural classes.

Enhanced second harmonic generation in a two-dimensional optical micro-cavity

We introduce a two-dimensional Bose-Einstein condensation model consisting of massive photon and photon-pair. Based on the new nonlinear model, the traditional process of second harmonics generation is reinvestigated. In order to describe the process, a new quantum phase, the harmonic phase, is introduced. The order parameter of the new physical phase is also given in this paper.

Spectrally resolved Franson interference

Franson interference can be used to test the nonlocal features of energy-time entanglement and has become a standard in quantum physics.However,most of the previous Franson interference experiments were demonstrated in the time domain,and the spectral properties of Franson interference have not been fully explored.Here,we theoretically and experimentally demonstrate spectrally resolved Franson interference using biphotons with different correlations,including positive correlation,negative correlation,and non-correlation.It is found that the joint spectral intensities of the biphotons can be modulated along both the signal and idler directions,which has potential applications in generating high-dimensional frequency entanglement and time-frequency grid states.This work may provide a new perspective for understanding the spectral-temporal properties of the Franson interferometer.