Charge-state independent anomalous transport for a wide range of different impurity species observed at Wendelstein 7-X

One approach being explored as a route to practical fusion energy uses heavy ion beams focused on an indirect drive target. Such beams will lose electrons while passing through background gas in the target chamber, and therefore it is necessary to assess the rate at which the charge state of the incident beam evolves on the way to the target. Accelerators designed primarily for nuclear physics or high energy physics experiments utilize ion sources that generate highly stripped ions in order to achieve high energies economically. As a result, accelerators capable of producing heavy ion beams of 10 to 40 MeV/amu with charge state 1 currently do not exist. Hence, the stripping cross sections used to model the performance of heavy ion fusion driver beams have, up to now, been based on theoretical calculations. We have investigated experimentally the stripping of 3.4 MeV/amu Kr+7 and Xe+11 in N2; 10.2 MeV/amu Ar+6 in He, N2, Ar, and Xe; 19 MeV/amu Ar+8 in He, N2, Ar, and Xe; 30 MeV He+1 in He, N2, Ar, and Xe; and 38 MeV/amu N+6 in He, N2, Ar, and Xe. The results of these measurements are compared with the theoretical calculations to assess their applicability over a wide range of parameters.

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An LLC and LCL-T Resonant Tanks Based Topology for Battery Charger Application

CPSS Transactions on Power Electronics and Applications ◽

10.24295/cpsstpea.2021.00025 ◽

2021 ◽

Vol 6 (4) ◽

pp. 263-275

Author(s):

Yuqi Wei ◽

Keyword(s):

Charge State ◽

Current Source ◽

Design Guidelines ◽

Constant Current ◽

Switching Frequency ◽

Resonant Converter ◽

Magnetic Components ◽

Wide Range ◽

Charging Current ◽

Llc Resonant Converter

To achieve the constant current (CC) and constant voltage (CV) charge of the lithium battery, the traditional LLC resonant converter requires the switching frequency varies in a wide range, which brings difficulty to the magnetic components design, and the system efficiency would also be degraded. In this article, a novel topology based on LLC and LCL-T resonant tanks is proposed to reduce the range of operating switching frequency. During the CC charge state, the proposed converter is operating with the LCL-T resonant tank, and it can be regarded as a current source, which provides constant charging current to the battery. During the CV charge state, the LCL-T resonant tank is bypassed and the structure of the proposed converter is modified to a traditional LLC resonant converter, and it is functioning as a CV source. Owing to the high accuracy of the CC and voltage sources, the required operating switching frequency range can be significantly reduced when compared with traditional LLC approaches. Operational principles and design guidelines for the proposed converter are described. Experiment and simulation results from a 180 W prototype are provided to validate the theoretical analysis.

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The Dependence of Spontaneous Charge Generation in Water on its Flow Rate in a Flow-Based Analytical System

Applied Sciences ◽

10.3390/app10072444 ◽

2020 ◽

Vol 10 (7) ◽

pp. 2444 ◽

Cited By ~ 1

Author(s):

Yuri D. Ivanov ◽

Andrey F. Kozlov ◽

Rafael A. Galiullin ◽

Anastasia A. Valueva ◽

Tatyana O. Pleshakova

Keyword(s):

Time Dependence ◽

Charge State ◽

Water Flow ◽

Flow Rate ◽

Charge Accumulation ◽

Measuring Cell ◽

Highly Sensitive ◽

Wide Range ◽

Analyte Solution ◽

Detection Of Biomolecules

Highly sensitive biosensor systems are particularly sensitive to the charge state of an analyte. This charge state can have either a positive (for instance, in case of increasing the efficiency of fishing of low-abundant proteins) or negative effect (for instance, in case of the appearance of charge jumps upon the injection of analyte solution into a measuring cell, what can cause undesirable parasitic signals). Previously, it was demonstrated that upon the pumping of analyte solution through polymeric communications of biosensors with a peristaltic pump at a low (~1 mL/min) flow rate, an accumulation of charge, transferred by the liquid drops from the feeding system into the measuring cell, is observed. At this point, the time dependence of charge accumulation has a linear-stepwise form. In the present study, the influence of the flow rate of water on the parameters of the time dependence of the accumulation of charge in such a system—including the influence on the stepwise charge accumulation—has been investigated. The measurements have been performed with a highly sensitive electrometer sensor at 38 °C, which corresponds to a pathological state of a human body. It has been found that a linear-stepwise time dependence of charge accumulation is observed in a wide range of water flow rates (V= 0.9 to 7.2 mL/min). At that point, upon increasing the flow rate with the transition from the drop-by-drop mode of water supply (0.9 mL/min) to the jet flow (7.2 mL/min), an increase in the absolute value of accumulated charge is observed, but the magnitude of the charge jumps does not change significantly. Thus, the amount of charge accumulated in the cell ambiguously depends on the water flow rate—i.e., this dependence can be non-linear. Accounting for the discovered phenomenon is important in the development of new, more accurate models describing physicochemical properties of aqueous solutions and hemodynamics. This effect should also be taken into account in the development of highly sensitive diagnostic systems intended for the detection of single biomarkers of pathologies in humans and crops, as well as in other living systems. In low-concentration systems, the occurrence of a charge can become a significant factor affecting the efficiency of detection of biomolecules and the reliability of the data obtained. The detection of biomolecules present in the solution at low concentrations is in high demand in medical diagnostics for the revelation of biomarkers at the early asymptomatic stage of various diseases, including aggressive forms of cancer.

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Momentum Space Topology and Non-Dissipative Currents †

Universe ◽

10.3390/universe4120146 ◽

2018 ◽

Vol 4 (12) ◽

pp. 146 ◽

Cited By ~ 5

Author(s):

Mikhail Zubkov ◽

Zakhar Khaidukov ◽

Ruslan Abramchuk

Keyword(s):

Hall Effect ◽

Momentum Space ◽

Heavy Ion ◽

High Energy ◽

Anomalous Transport ◽

Relativistic Heavy Ion Collisions ◽

Solid State Physics ◽

Space Topology ◽

Chiral Magnetic Effect ◽

Wide Range

Relativistic heavy ion collisions represent an arena for the probe of various anomalous transport effects. Those effects, in turn, reveal the correspondence between the solid state physics and the high energy physics, which share the common formalism of quantum field theory. It may be shown that for the wide range of field–theoretic models, the response of various nondissipative currents to the external gauge fields is determined by the momentum space topological invariants. Thus, the anomalous transport appears to be related to the investigation of momentum space topology—the approach developed earlier mainly in the condensed matter theory. Within this methodology we analyse systematically the anomalous transport phenomena, which include, in particular, the anomalous quantum Hall effect, the chiral separation effect, the chiral magnetic effect, the chiral vortical effect and the rotational Hall effect.

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xcalib: a focal spot calibrator for intense X-ray free-electron laser pulses based on the charge state distributions of light atoms

Journal of Synchrotron Radiation ◽

10.1107/s1600577519003564 ◽

2019 ◽

Vol 26 (4) ◽

pp. 1017-1030 ◽

Cited By ~ 3

Author(s):

Koudai Toyota ◽

Zoltan Jurek ◽

Sang-Kil Son ◽

Hironobu Fukuzawa ◽

Kiyoshi Ueda ◽

...

Keyword(s):

Charge State ◽

Free Electron ◽

Free Electron Laser ◽

Focal Spot ◽

Experimental Results ◽

Experimental Conditions ◽

X Ray ◽

Wide Range ◽

Light Atoms ◽

Charge State Distributions

The xcalib toolkit has been developed to calibrate the beam profile of an X-ray free-electron laser (XFEL) at the focal spot based on the experimental charge state distributions (CSDs) of light atoms. Characterization of the fluence distribution at the focal spot is essential to perform the volume integrations of physical quantities for a quantitative comparison between theoretical and experimental results, especially for fluence-dependent quantities. The use of the CSDs of light atoms is advantageous because CSDs directly reflect experimental conditions at the focal spot, and the properties of light atoms have been well established in both theory and experiment. Theoretical CSDs are obtained using xatom, a toolkit to calculate atomic electronic structure and to simulate ionization dynamics of atoms exposed to intense XFEL pulses, which involves highly excited multiple core-hole states. Employing a simple function with a few parameters, the spatial profile of an XFEL beam is determined by minimizing the difference between theoretical and experimental results. The optimization procedure employing the reinforcement learning technique can automatize and organize calibration procedures which, before, had been performed manually. xcalib has high flexibility, simultaneously combining different optimization methods, sets of charge states, and a wide range of parameter space. Hence, in combination with xatom, xcalib serves as a comprehensive tool to calibrate the fluence profile of a tightly focused XFEL beam in the interaction region.

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Modulation of nitrogen vacancy charge state and fluorescence in nanodiamonds using electrochemical potential

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1504451113 ◽

2016 ◽

Vol 113 (15) ◽

pp. 3938-3943 ◽

Cited By ~ 36

Author(s):

Sinan Karaveli ◽

Ophir Gaathon ◽

Abraham Wolcott ◽

Reyu Sakakibara ◽

Or A. Shemesh ◽

...

Keyword(s):

Charge State ◽

Quantum Information Processing ◽

Nitrogen Vacancy ◽

Wide Field ◽

Fluorescence Sensing ◽

Biologically Relevant ◽

State Dependent ◽

Wide Range ◽

Electrochemical Potentials ◽

Nv Centers

The negatively charged nitrogen vacancy (NV−) center in diamond has attracted strong interest for a wide range of sensing and quantum information processing applications. To this end, recent work has focused on controlling the NV charge state, whose stability strongly depends on its electrostatic environment. Here, we demonstrate that the charge state and fluorescence dynamics of single NV centers in nanodiamonds with different surface terminations can be controlled by an externally applied potential difference in an electrochemical cell. The voltage dependence of the NV charge state can be used to stabilize the NV− state for spin-based sensing protocols and provides a method of charge state-dependent fluorescence sensing of electrochemical potentials. We detect clear NV fluorescence modulation for voltage changes down to 100 mV, with a single NV and down to 20 mV with multiple NV centers in a wide-field imaging mode. These results suggest that NV centers in nanodiamonds could enable parallel optical detection of biologically relevant electrochemical potentials.

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Recent Applications of High Resolution Electron Microscopy to Crystalline Arrays of Virus Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070199 ◽

1978 ◽

Vol 36 (3) ◽

pp. 470-482 ◽

Cited By ~ 1

Author(s):

R.W. Horne

Keyword(s):

Electron Microscopy ◽

Image Processing ◽

Analytical Techniques ◽

Staining Technique ◽

High Resolution Electron Microscopy ◽

Optical Diffraction ◽

Full Potential ◽

Virus Particles ◽

Resolution Electron ◽

Wide Range

The technique of surrounding virus particles with a neutralised electron dense stain was described at the Fourth International Congress on Electron Microscopy, Berlin 1958 (see Home & Brenner, 1960, p. 625). For many years the negative staining technique in one form or another, has been applied to a wide range of biological materials. However, the full potential of the method has only recently been explored following the development and applications of optical diffraction and computer image analytical techniques to electron micrographs (cf. De Hosier & Klug, 1968; Markham 1968; Crowther et al., 1970; Home & Markham, 1973; Klug & Berger, 1974; Crowther & Klug, 1975). These image processing procedures have allowed a more precise and quantitative approach to be made concerning the interpretation, measurement and reconstruction of repeating features in certain biological systems.

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Microfabrication research at the National Submicron Facility

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074331 ◽

1983 ◽

Vol 41 ◽

pp. 86-89

Author(s):

E.D. Wolf

Keyword(s):

Integrated Circuits ◽

Particle Physics ◽

High Speed ◽

New Technology ◽

High Energy ◽

High Energy Particle ◽

New Science ◽

Wide Range ◽

Intermediate Domain ◽

Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

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Application of TEM to Deformation, Wear, and Fracture of Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052377 ◽

1974 ◽

Vol 32 ◽

pp. 472-473

Author(s):

B. J. Hockey

Keyword(s):

Wear Resistance ◽

High Temperature ◽

Mechanical Behavior ◽

Brittle Materials ◽

High Temperature Strength ◽

Wide Range ◽

Corrosive Environments ◽

Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

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