Diffusion-Controlled Electron Transfer Processes and Power-Law Statistics of Fluorescence Intermittency of Nanoparticles

A mechanism involving diffusion-controlled electron transfer processes in Debye and non-Debye dielectric media is proposed to elucidate the power-law distribution for the lifetime of a blinking quantum dot. This model leads to two complementary regimes of power law with a sum of the exponents equal to 2, and to a specific value for the exponent in terms of a distribution of the diffusion correlation times. It also links the exponential bending tail with energetic and kinetic parameters

Chain dynamics and power-law distance fluctuations of single-molecule systems

Chain-dynamics-induced distance fluctuations between any two points in a finite chain with or without cross links are investigated. This model leads to three regimes of temporal behavior for distance autocorrelation: (i) initial flat time dependence, (ii) t–alpha power law, and (iii) long-time exponential decay. For an ideal Rouse chain with frequency-independent friction, alpha=(1/2). The span of the characteristic power-law behavior of a long chain could be reduced significantly with the presence of cross links

Distance versus energy fluctuations and electron transfer in single protein molecules

Stochastic nature due to distance and energy fluctuations of single protein molecules involved in electron-transfer (ET) reactions is studied. Distance fluctuations have been assumed previously for causing the slow fluctuations in the ET rates between a donor-acceptor pair constrained to a native protein. Although the observed t–1/2 power law can be derived using Langevin dynamics with a simple chain model, some discrepancies exist. The friction coefficient and the Rouse segment time constant deduced from experimental data are several orders of magnitude too large, even though the extracted force constant is reasonable. Therefore, questions are raised about the distance-fluctuation mechanism and the activationless ET hypothesis. As an alternative mechanism, we considered fluctuations in activation energy and analyzed the data from two different single protein experiments to determine spectral distribution of energy fluctuations

Sedenion algebra for three lepton/quark generations and its relations to SU(5)

In this work, we analyze two models beyond the Standard Models descriptions that make ad hoc hypotheses of three point-like lepton and quark generations without explanations of their physical origins. Instead of using the same Dirac equation involving four anti-commutative matrices for all such structure-less elementary particles, we consider in the first model the use of sixteen direct-product matrices of quaternions that are related to Diracs gamma matrices. This associative direct-product matrix model could not generate three fermion generations satisfying Einsteins mass-energy relation. We show that sedenion algebra contains five distinct quaternion sub-algebras and three octonion sub-algebras but with a common intersecting quaternion algebra. This model naturally leads to precisely three generations as each of the non-associative octonion sub-algebra leads to one fermion generation. Moreover, we demonstrate the use of basic sedenion.Comment: 19 pages, 5 figure

A unified sedenion model for the origins of three generations of charged and neutral leptons, flavor mixing, mass oscillations and small masses of neutrinos

We present a unified model without the need for an ad hoc Standard Model hypothesis; we explain why there are three generations of charged and neutral leptons, why neutrinos have a vanishingly small mass, and why flavor-mixing emerges and mass oscillations occur. We show that the sedenion algebra contains three types of non-associative octonion algebra, with each corresponding to a generation of leptons. By incorporating extra degrees of freedom, the generalized higher dimensional Dirac equation accounts for the internal structural dynamics. This study sheds light on the intrinsic physical properties of three generations of charged leptons and neutrinos and their distinctive spacetime structures.Comment: 22 pages, 6 figure

Dynamics and control of gold-encapped gallium arsenide nanowires imaged by 4D electron microscopy

Eutectic related reaction is a special chemical/physical reaction involving multiple phases, solid and liquid. Visualization of phase reaction of composite nanomaterials with high spatial and temporal resolution provides a key understanding of alloy growth with important industrial applications. However, it has been a rather challenging task. Here we report the direct imaging and control of the phase reaction dynamics of a single, as-grown free-standing gallium arsenide nanowire encapped with a gold nanoparticle, free from environmental confinement or disturbance, using four-dimensional electron microscopy. The non-destructive preparation of as-grown free-standing nanowires without supporting films allows us to study their anisotropic properties in their native environment with better statistical character. A laser heating pulse initiates the eutectic related reaction at a temperature much lower than the melting points of the composite materials, followed by a precisely time-delayed electron pulse to visualize the irreversible transient states of nucleation, growth and solidification of the complex. Combined with theoretical modeling, useful thermodynamic parameters of the newly formed alloy phases and their crystal structures could be determined. This technique of dynamical control and 4D imaging of phase reaction processes on the nanometer-ultrafast time scale open new venues for engineering various reactions in a wide variety of other systems

Plasma-induced unconventional shock waves on oil surfaces

Electric corona discharge in a multi-phase system results in complex electro-hydrodynamic phenomena. We observed unconventional shock wave propagation on an oil thin film sprayed over a polymer-coated conductor. A hair-thin single shock wave arose when the high voltage bias of an overhung steel needle was abruptly removed. However, such solitary waves possess neither interference nor reflection properties commonly known for ordinary waves, and also differ from the solitons in a canal or an optical fiber. We also observed time-retarded movement for dispersed oil droplets at various distances from the epicenter which have no physical contact, as if a wave propagating on a continuous medium. Such a causality phenomenon for noncontact droplets to move resembling wave propagation could not be possibly described by the conventional surface wave equation. Our systematic studies reveal a mechanism involving oil surface charges driven by reminiscent electric fields in the air when the needle bias is suddenly removed