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91.
In quantum physics all experimental information is discrete and stochastic. But the values of physical quantities are considered to depict definite properties of the physical world. Thus physical quantities should be identified with mathematical variables which are derived from the experimental data, but which exhibit as little randomness as possible. We look for such variables in two examples by investigating how it is possible to arrive at a value of a physical quantity from intrinsically stochastic data. With the aid of standard probability calculus and elementary information theory, we are necessarily led to the quantum theoretical phases and state vectors as the first candidates for physical quantities.  相似文献   
92.
《Physics letters. A》2020,384(26):126662
We study the dynamic of magneto-polaron condensate in monolayer two dimensional (2D) transition metal dichalcogenides (TMDs) materials of 2H types in triangular quantum well potential. Within both the quantum mechanical Schrödinger approach (QMSA) and the improved Wigner-Brillouin theory (IWBT), Landau energies levels (LELs) are derived. We have shown that the magneto-polaron condensation is enhanced in monolayer MoSe2 compared to MoS2, WS2 and WSe2. We derive various levels by increasing a magnetic field and laser parameter. We show that the quantum confinement lifts the degeneracy of the Landau levels (LLs) resulting in an anticrossing and crossing. The dephasing effect due to the quantum well potential's parameter plays an important role in the magneto-polaron energy corrections, which are also affected by the amplitude of the laser field. The system presents Stückelberg oscillations which is important for practical applications.  相似文献   
93.
We discuss the motion of substance in a channel containing nodes of a network. Each node of the channel can exchange substance with: (i) neighboring nodes of the channel, (ii) network nodes which do not belong to the channel, and (iii) environment of the network. The new point in this study is that we assume possibility for exchange of substance among flows of substance between nodes of the channel and: (i) nodes that belong to the network but do not belong to the channel and (ii) environment of the network. This leads to an extension of the model of motion of substance and the extended model contains previous models as particular cases. We use a discrete-time model of motion of substance and consider a stationary regime of motion of substance in a channel containing a finite number of nodes. As results of the study, we obtain a class of probability distributions connected to the amount of substance in nodes of the channel. We prove that the obtained class of distributions contains all truncated discrete probability distributions of discrete random variable ω which can take values 0,1,,N. Theory for the case of a channel containing infinite number of nodes is presented in Appendix A. The continuous version of the discussed discrete probability distributions is described in Appendix B. The discussed extended model and obtained results can be used for the study of phenomena that can be modeled by flows in networks: motion of resources, traffic flows, motion of migrants, etc.  相似文献   
94.
翟晓东  丁艳军  彭志敏  罗锐 《物理学报》2012,61(12):123301-123301
本文利用分子光谱理论系统的计算和分析N2第二正带系(C3u→B3g)的发射光谱, 以研究光谱强度的分布规律与不同温度条件和气体条件的关系. 基于N2的三重态能级结构特性, 重点计算和讨论了发射光谱的概个重要参数: 通过求解高、低电子态的哈密顿矩阵得到了振转能级特性; 利用r质心近似法求取了能级间跃迁的电偶极矩函数和爱因斯坦跃迁概率; 进而计算了不同振动和转动温度条件下谱线的强度分布. 进行了N2和Ar的混合放电实验, 利用实验光谱数据同理论结果进行拟合分析, 确定了N2分子的振动温度和转动温度分别约为4300 K和800 K. 另外由于潘宁离化效应, N2浓度减小时谱线强度呈现先增强后减弱的趋势. 实验结果很好的验证了N2第二正带系光谱理论计算的正确性.  相似文献   
95.
96.
This article presents an experimental investigation on the merging probability of buoyancy-controlled jet flames. Two rectangular jet nozzles with different aspect ratios and heat release rates were studied in the open space. The nozzles of the same area with dimensions of 1.5 × 24, 3 × 12, and 6 × 6 mm were used in this article. It is found that the merging probability increases with the heat release rate and decreases with the space between these two nozzles. A model to predict the merging probability has been developed, which is proportional to a dimensionless parameter linearly within a certain scope.  相似文献   
97.
Thermal and dielectric loss properties of Na2O-Bi2O3-TiO2-P2O5 phosphate glasses, have been studied by the differential scanning calorimetry (DSC) and electrical factor loss (tgi) measurements. The variation of tgi has been followed along two lines inside the quaternary systems Na2O-Bi2O3-5TiO2-P2O5 and Na2O-5Bi2O3-TiO2-P2O5. Experiments have been carried out from ambient temperature to 450°C and show a strong influence of sodium, bismuth and titanium ions on Tg and tgi.  相似文献   
98.
99.
Nanocomposite electrodes of recently identified polyanion cathode materials comprising Li x M2(MoO4)3 {0 ≤ x < 3} [M = Co, Ni] and nanosized carbon having ~10 nm particle size were found to show remarkable improvement in their discharge capacity compared to the one prepared with acetylene black. The addition of nanosized carbon as a conductive additive offered improved initial discharge capacity of 121 mAh/g between 3.5–2.0 V vs Li/Li. The cause for such an increase could be firmly attributed to the filling up of the grain–grain contact area of the active material, facilitating the intimate grain–grain contacts in the composite structure leading to enhanced capacity delivery. As for the nanocomposite Li x Co2(MoO4)3, it was found that at least 55% of its first discharge capacity was retained at the end of 20th cycle compared to its analogous counterpart, Li x Ni2(MoO4)3. Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006.  相似文献   
100.
Stochastic mechanism of relaxation, in which a dipole waits until a favourable condition for reorientation exists, is discussed. Assuming that an imposed direction of a dipole moment may be changed when a migrating defect reaches the dipole, we present a mathematically rigorous scheme relating the local random characteristics of a macroscopic system to its effective relaxation behaviour. We derive a relaxation function (the Burr survival probability) that is characterized by the stretched exponential or the power-law behaviour.  相似文献   
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