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Discrete kink dynamics in hydrogen-bonded chains I: The one-component model  [PDF]
V. M. Karpan,Y. Zolotaryuk,P. L. Christiansen,A. V. Zolotaryuk
Physics , 2002, DOI: 10.1103/PhysRevE.66.066603
Abstract: We study topological solitary waves (kinks and antikinks) in a nonlinear one-dimensional Klein-Gordon chain with the on-site potential of a double-Morse type. This chain is used to describe the collective proton dynamics in quasi-one-dimensional networks of hydrogen bonds, where the on-site potential plays role of the proton potential in the hydrogen bond. The system supports a rich variety of stationary kink solutions with different symmetry properties. We study the stability and bifurcation structure of all these stationary kink states. An exactly solvable model with a piecewise ``parabola-constant'' approximation of the double-Morse potential is suggested and studied analytically. The dependence of the Peierls-Nabarro potential on the system parameters is studied. Discrete travelling-wave solutions of a narrow permanent profile are shown to exist, depending on the anharmonicity of the Morse potential and the cooperativity of the hydrogen bond (the coupling constant of the interaction between nearest-neighbor protons).
纵扭复合型超声电机预压力和输出扭矩的关系  [PDF]
摩擦学学报 , 2001,
Abstract: 建立了纵扭复合型超声电机定子和转子之间的接触模型,根据模型讨论了预压力、纵振激振电压、扭振激振电压、摩擦力及电机能提供的最大扭矩之间的关系。指出在一定的条件下,施加某一预压力时电机的输出扭矩最大。所得计算结果和实验结果基本吻合。
Quantum kink and its excitations  [PDF]
Arttu Rajantie,David J. Weir
Physics , 2009, DOI: 10.1088/1126-6708/2009/04/068
Abstract: We show how detailed properties of a kink in quantum field theory can be extracted from field correlation functions. This makes it possible to study quantum kinks in a fully non-perturbative way using Monte Carlo simulations. We demonstrate this by calculating the kink mass as well as the spectrum and approximate wave functions of its excitations. This way of measuring the kink mass has clear advantages over the existing approaches based on creation and annihilation operators or the kink free energy. Our methods are straightforward to generalise to more realistic theories and other defect types.
Forced kink of $λφ^4$ mode  [PDF]
Ya. M. Shnir
Physics , 1997,
Abstract: The motion of a one-dimensional kink and its energy losses are considered as a model of interaction of nontrivial topological field configurations with external fields.
安全扭叉  [PDF]
地质与勘探 , 1974,
Abstract: 扭叉是机械拧卸管的辅助工具.过去所用的扭叉,在回转离心力的作用下,常会飞离钻杆卡槽,对井口操作人员的安全有很大威胁.为了解决这个问题,探矿安全组同志深入机台,征求工人同志意见,设计试制了安全扭叉(如右图),经过反复实践,不断修改,这种扭叉已在机台应用并投入铸钢生产.此安全扭叉重量同原来的扭叉相近,操作也较方便.由于其开口的方向相反,所以
Surface lattice kink solitons  [PDF]
Yaroslav V. Kartashov,Victor A. Vysloukh,Lluis Torner
Physics , 2006, DOI: 10.1364/OE.14.012365
Abstract: We predict theoretically that surface of an optical lattice imprinted in defocusing nonlinear media can support shock, or kink waves. Such new surface waves contain a modulationally stable pedestal and are strongly localized at the edge of the optical lattice due to Bragg-type reflection. The kink steepness and localization degree can be controlled by the lattice depth. We found two types of kinks, which exhibit distinct stability properties for each finite gap in the lattice spectrum. Our findings open the way to experimental observation of optical surface kink waves.
热激损伤对牛孤雌激活胚胎后续发育的影响  [PDF]
牲畜兽医学报 , 2010,
Abstract: ?为了研究早期胚胎核与胞质对热激的应激反应,以及产生应激后二者之间的相互作用对胚胎体外发育、合子期激活基因的表达及胚胎细胞凋亡的影响。本研究将孤雌激活胚随机分为2组分别于38.5或41℃培养7h;随后将二者核进行置换,使用正常培养的胚胎与热激胚胎进行核置换,分别构建热激核-正常胞质重构胚以及热激胞质-正常核重构胚,检测了核质置换胚胎的体外发育率、合子激活基因的表达和胚胎凋亡情况。结果,当正常核移入41℃热激的卵胞质,重构胚的发育率显著下降;热激后的核质置换胚胎中存在合子基因激活不完全的现象,这种情况主要存在于热激胞质-正常核重构胚中;热激能诱导胚胎发生细胞凋亡,早期胚胎的胞质对热激更敏感,并在后期的诱导凋亡中起到主导作用。这些结果表明,虽然热激对核和胞质都有损伤,但胞质对热激损伤更为敏感。早期胚胎受到热激后导致发育能力降低的易感性主要是由胞质所引起的;早期胚胎受到热激可能会损伤到卵胞质中的母源因子,即使与正常核构成重构胚也依然会导致合子基因表达异常;并且胞质受到热激损伤会在热激诱导的凋亡机制中起到比核更大的作用。
On the black-hole kink  [PDF]
Pedro F. Gonzalez-Diaz
Physics , 1996, DOI: 10.1142/S0218271897000054
Abstract: By allowing the light cones to tip over on hypersurfaces according to the conservation laws of an one-kink in static, Schwarzschild black hole metric, we show that in the quantum regime there also exist instantons whose finite imaginary action gives the probability of occurrence of the kink metric corresponding to single chargeless, nonrotating black hole taking place in pairs, the holes of each pair being joined on an interior surface, beyond the horizon.
Centrifugal deformations of the gravitational kink  [PDF]
Paolo Maraner,Jiannis K. Pachos
Physics , 2008, DOI: 10.1016/j.physleta.2009.05.051
Abstract: The Kaluza-Klein reduction of 4d conformally flat spacetimes is reconsidered. The corresponding 3d equations are shown to be equivalent to 2d gravitational kink equations augmented by a centrifugal term. For space-like gauge fields and non-trivial values of the centrifugal term the gravitational kink solutions describe a spacetime that is divided in two disconnected regions.
On the Existence of Kink-(Soliton-)States  [PDF]
Dirk Schlingemann
Mathematics , 1995, DOI: 10.1142/S0129055X96000433
Abstract: There are several two dimensional quantum field theory models which are equipped with different vacuum states. For example the Sine-Gordon- and the $\phi^4_2$-model. It is known that in these models there are also states, called soliton- or kink-states, which interpolate different vacua. We consider the following question: Which are the properties a pair of vacuum sates must have, such that an interpolating kink-state can be constructed? Since we are interested in structural aspects and not in specific details of a given model, we are going to discuss this question in the framework of algebraic quantum field theory which includes, for example, the $P(\phi)_2$-models. We have shown that for a large class of vacuum states, including the vacua of the $P(\phi)_2$-models, there is a natural way to construct an interpolating kink-state.
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