We present extreme ultraviolet and visible spectra of promethiumlike tungsten and gold obtained with an electron beam ion trap. Although the contributions from a few charge states are involved in the spectra, the char...
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We present extreme ultraviolet and visible spectra of promethiumlike tungsten and gold obtained with an electron beam ion trap. Although the contributions from a few charge states are involved in the spectra, the charge state of the ion assigned to the observed lines is definitely identified by the time-of-flight (TOF) analysis of the ions performed at the same time with the spectroscopic measurements. Experimental results are compared with collisional-radiative model calculations as well as previous experimental and theoretical studies. Some ambiguous identifications in the previous observations have been clarified owing to the definite identification by the TOF analysis.
Metric type II radio bursts are usually early indicators of CME-driven shocks and other space weather phenomena in the solar corona. This paper presents a detailed investigation of the spectral properties of band spli...
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Population structure has been known to substantially affect evolutionary dynamics. Networks that promote the spreading of fitter mutants are called amplifiers of selection, and those that suppress the spreading of fit...
Due to unique physiochemical properties of carbon nanotubes (CNTs), they are utilized in biomedicine applications including biomedical engineering, tissue engineering, drug delivery, gene therapy and biosensor enginee...
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Due to unique physiochemical properties of carbon nanotubes (CNTs), they are utilized in biomedicine applications including biomedical engineering, tissue engineering, drug delivery, gene therapy and biosensor engineering. Studies have been shown that carbon nanotube have a large propensity to interact with biomembranes; therefore, the toxicity of these nanomaterials and understanding the way CNTs interact with cell become more important. Recently, enormous efforts have been made to understand the molecular mechanism of CNTs and lipid bilayer interaction. Because of the relative large scale of lipid bilayer, quantum ab-initio methods are not common for such systems; consequently, both all atom and coarse grained molecular dynamic simulation (MD) are widely performed. For simulation of such system it is important to apply the correct physical and structural properties of carbon nanotube in the simulation, for instance with density functional theory (DFT) modeling it has been clear that, for open-ended CNTs not only is there unsaturated bonds at the end of tube, but also has a significant dipole moment which should not neglected and their quantity correspond to nanotube chirality and diameter. The aim of this work is to discuss the partial charges distribution along the carbon nanotubes and describe how they affect in CNTs -lipid bilayer interaction by free energy calculation. Our Simulation consist of two stage, first partial charges for pristine and functional carbon nanotube were determined by DFT calculation then results were applied to molecular dynamic force field. The DFT simulation computes partial charges quantity at the ends of nanotube and its results indicate that partial charges for functional nanotubes are higher than pristine nanotubes. The MD simulation determines that nanotubes interaction energy with biomembrane is highly strong, about 120 kcal/mol.
Cytoplasmic streaming circulates the contents of large eukaryotic cells, often with complex flow geometries. A largely unanswered question is the significance of these flows for molecular transport and mixing. Motivat...
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Cytoplasmic streaming circulates the contents of large eukaryotic cells, often with complex flow geometries. A largely unanswered question is the significance of these flows for molecular transport and mixing. Motivated by “rotational streaming” in Characean algae, we solve the advection-diffusion dynamics of flow in a cylinder with bidirectional helical forcing at the wall. A circulatory flow transverse to the cylinder’s long axis, akin to Dean vortices at finite Reynolds numbers, arises from the chiral geometry. Strongly enhanced lateral transport and longitudinal homogenization occur if the transverse Péclet number is sufficiently large, with scaling laws arising from boundary layers.
We measure photoelectron angular distributions of single ionization of krypton and xenon atoms by laser pulses at 1320 nm, 0.2–1.0×1014 W/cm2, and observe that the yield of near-zero-momentum electrons in the s...
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We measure photoelectron angular distributions of single ionization of krypton and xenon atoms by laser pulses at 1320 nm, 0.2–1.0×1014 W/cm2, and observe that the yield of near-zero-momentum electrons in the strong-field tunneling ionization regime is significantly suppressed. Semiclassical simulations indicate that this local ionization suppression effect can be attributed to a fraction of the tunneled electrons that are released in a certain window of the initial field phase and transverse velocity are ejected into Rydberg elliptical orbits with a frequency much smaller than that of the laser; i.e., the corresponding atoms are stabilized. These electrons with high-lying atomic orbits are thus prevented from ionization, resulting in the substantially reduced near-zero-momentum electron yield. The refined transition between the Rydberg states of the stabilized atoms has implication on the THz radiation from gas targets in strong laser fields.
The study of parametric instabilities has played a crucial role in understanding energy transfer to plasma and, with that, the development of key applications such as inertial confinement fusion. When the densities ar...
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The study of parametric instabilities has played a crucial role in understanding energy transfer to plasma and, with that, the development of key applications such as inertial confinement fusion. When the densities are between 0.11nc≲ne≲0.14nc and the electron temperature is in inertial confinement fusion-relevant temperatures, anomalous hot electrons with kinetic energies above 100keV are generated. Here a new electron acceleration mechanism—the anti-Stokes Langmuir decay instability cascade of forward stimulated Raman scattering—is investigated. This mechanism potentially explains anomalous energetic electron generation in indirectly driven inertial confinement fusion experiments, it also provides a new way of accelerating electrons to higher energy for applications such as novel x-ray sources.
We have experimentally and theoretically studied the fragmentation dynamics of argon trimer (Ar3) in intense laser fields. By coincidently measuring the momentum vectors, we obtained the emission geometry of the three...
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We have experimentally and theoretically studied the fragmentation dynamics of argon trimer (Ar3) in intense laser fields. By coincidently measuring the momentum vectors, we obtained the emission geometry of the three fragmental ions produced in the three-body fragmentation process. In addition to the direct Coulomb explosion channels, we observed the indirect Coulomb explosion channels with Rydberg excitation. We have further developed a classical polyatomic molecular ensemble model, in which all interactions among electrons and nuclei are fully included, to simulate the fragmentation dynamics of argon trimer in intense laser fields. The experimental observations have been reproduced by the model calculation. The simulations show that the Rydberg excitation modifies the kinetic energy release as well as the emission geometry of fragmental ions during the explosion process. The study provides insight into the correlation dynamics of electrons and nuclei of many-body physics driven by intense laser fields.
Two simple Markov processes are examined, one in discrete and one in continuous time, arising from idealized versions of a transmission protocol for mobile networks. We consider two independent walkers moving with con...
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