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81.
Xiang-Yao Wu Bai-Jun Zhang Hai-Bo Li Xiao-Jing Liu Jing-Wu Li Yi-Qing Guo 《International Journal of Theoretical Physics》2009,48(7):2027-2035
It is well known that Schr?dinger’s equation is only suitable for the particle in conservative force field. In atomic and
molecular field, a particle can suffer the action of non-conservative force. In this paper, a new quantum wave equation is
proposed, which can describe the particle in non-conservative force field. We think the new quantum wave equation can be used
in many fields. 相似文献
82.
利用探针辅助的脉冲激光诱导负离子剥离诊断技术对掺入5%O_2的容性耦合Ar等离子体电负特性进行了诊断研究.首先详细解析了脉冲激光剥离后探针的电信号,分析了探针偏压在低于或高于空间电位下的探针收集信号特征;根据探针偏压与探针收集信号之间的依赖关系,用来描述Ar+O_2等离子体电负特性的等离子体电负度被定义为脉冲激光剥离出的电子电流与偏压高于空间电位的探针收集到的背景电子电流的饱和比值,并对等离子体电负度随放电气压、射频功率以及轴向位置的变化进行了诊断测量.实验结果表明等离子体的电负度随着射频功率的增加而减小、随着放电气压的上升而变大;由于非对称电极的分布特性,在轴向方向上靠近功率电极时等离子体电负度有升高的趋势,这种趋势可能与鞘层边界附近二次电子的动力学行为以及负离子的产生与消失过程有关. 相似文献
83.
On the contribution of a hard galactic plane component to the excesses of secondary particles 下载免费PDF全文
The standard model of cosmic ray propagation has been very successful in explaining all kinds of galactic cosmic ray spectra. However, high precision measurement have recently revealed an appreciable discrepancy between data and model expectations, from spectrum observations of gamma-rays, e+/e- and probably the B=C ratio starting from ~10 GeV energy . In this work, we propose that a hard galactic plane component, supplied by the fresh cosmic ray sources and detained by local magnetic elds, can contribute additional secondary particles interacting with local materials. By properly choosing the intensity and spectral index of the harder component up to multi-T eV energy , a two-component gamma-ray spectrum is obtained and agrees very well with the observation. Simultaneously , the expected neutrino numbers from the galactic plane could contribute ~60% of IceCube observed neutrino number below a few hundreds of TeV under our model. In addition to these studies, we nd that the same pp-collision process responsible for the excess gamma ray emission could account for a signi cant amount of the positron excess, but a more detailed mechanism is needed for a full agreement. It is expected that the excesses in the p=p and B=C ratio will show up when energy is above ~10 GeV. We look forward this model being tested in the near future by new observations from AMS02, IceCube, AS-gamma, HA WC and future experiments such as LHASSO, HiSCORE and CTA. 相似文献
84.
合金团簇所具备的催化和光学等方面特性与团簇的尺寸、元素组成和元素序列密切关联,因而确定其稳定结构是研究纳米团簇合金性质的首要任务.本文利用基于内核构建的自适应免疫优化算法研究了完整元素组成的CunAum(n+m=61及79)二元合金团簇的稳定结构.应用多体Gupta势函数描述Cu-Au团簇原子间的相互作用.研究结果表明:对于CunAum(n+m=61)团簇,除了当n=12-15时为由三个双二十面体面面相连组成的环状结构外,其余均为二十面体结构.原子总数为79的Cu-Au合金团簇包括堆积缺陷的面心立方结构、双面心立方结构、二十面体、十面体和由四个双二十面体面面相连组成的环状结构.且当Au原子比例高和低时其主要构型分别为二十面体和十面体.此外,还分析了Cu-Au合金团簇结构势能量的分布情况及团簇的相对稳定性.原子分布规律显示Cu原子趋于占据内层,而Au原子趋向于分布在外层. 相似文献
85.
通过调节动静态理想光子禁带模型库的结构参数,研究了初态处于激发态的两能级原子系统的演化.在静态无调制下研究理想光子禁带模型库环境的半宽度、中心谐振频率及比重对原子布居数演化的影响.在理想光子禁带库环境的中心共振频率受动态调制下,其调制形式分别取为:矩形单次脉冲、矩形周期性脉冲和缓变连续周期.在此基础上讨论动态调制形式的不同对原子布居数演化的影响.无论怎样的动态调制形式,衰减抑制在原子系统的演化过程还是有较明显的体现.这样就使得利用环境变化对原子布居数和原子系统相干性演化调制的想法得以实现. 相似文献
86.
The scale-invariance behavior has been widely observed in English or other phonetic language texts. In the present study, we examine whether the semantic language, Chinese can also show this behavior. Typically, the scale-invariance behavior is examined in the series of character intervals for the four great Chinese novels by a method of detrended fluctuation analysis. We observe that the scale-invariance behavior characterized by a scaling exponent around 0.60 exists in each novel. Moreover, we divide each novel into three parts with equal number of chapters, and we also observe the existence of scale-invariance in the interval series for each part. Interestingly, we find that there is evident difference in the scaling exponents between the first (or second) part and the third part in the novel of A dream of red mansions, and the difference between parts is not evident for the other three novels. Our observation suggests that there are two writing styles in A dream of red mansions, which are consistent with current prevailing view that the first 80 chapters and the last 40 chapters were accomplished by Xueqin Cao and E Gao, respectively. Our method may shed light on the identification of writing styles in written texts. 相似文献
87.
Phenomena of electron, neutron, atomic and molecular diffraction have been studied in many experiments, and these experiments have been explained by some theoretical works. We study electronic double-slit diffraction with a quantum mechanical approach and obtain the following results: (1) When the ratio of d + a /a=n (n = 1,2, 3,...), orders n, 2n, 3n,... are missing in diffraction pattern. (2) When the ratio of d+a/a≠ n (n =1,2, 3,...), there is a not missing order in diffraction pattern. (3) The slit thickness c has a large affect on the electronic diffraction pattern, which is a new quantum effect. We believe that all the predictions in our work can be tested by the electronic double slit diffraction experiment. 相似文献
88.
Bing-Qiang Qiao Wei Liu Meng-Jie Zhao Xiao-Jun Bi Yi-Qing Guo 《Frontiers of Physics》2022,17(4):44501
The Tibet ASγ experiment just reported their measurement of sub-PeV diffuse gamma-ray emission from the Galactic disk, with the highest energy up to 957 TeV. These diffuse gamma rays are most likely the hadronic origin by cosmic ray (CR) interaction with interstellar gas in the galaxy. This measurement provides direct evidence to the hypothesis that the Galactic Cosmic Rays (GCRs) can be accelerated beyond PeV energies. In this work, we try to explain the sub-PeV diffuse gamma-ray spectrum with different CR propagation models. We find that there is a tension between the sub-PeV diffuse gamma-ray and the local CR spectrum. To describe the sub-PeV diffuse gamma-ray flux, it generally requires larger local CR flux than measurement in the knee region. We further calculate the PeV neutrino flux from the CR propagation model. Even all of these sub-PeV diffuse gamma rays originate from the propagation, the Galactic Neutrinos (GNs) only account for less than ~15% of observed flux, most of which are still from extragalactic sources. 相似文献
89.
Yi-Qing Zhang Jing Cui Shu-Min Zhang Qi Zhang Xiang Li 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(2):26
Modelling temporal networks of human face-to-face contacts is vital both for understanding the spread of airborne pathogens and word-of-mouth spreading of information. Although many efforts have been devoted to model these temporal networks, there are still two important social features, public activity and individual reachability, have been ignored in these models. Here we present a simple model that captures these two features and other typical properties of empirical face-to-face contact networks. The model describes agents which are characterized by an attractiveness to slow down the motion of nearby people, have event-triggered active probability and perform an activity-dependent biased random walk in a square box with periodic boundary. The model quantitatively reproduces two empirical temporal networks of human face-to-face contacts which are testified by their network properties and the epidemic spread dynamics on them. 相似文献
90.