Low-energy single-pulse surface stimulation defibrillates large mammalian ventricles

A comparative study of single-and double-pulse laser induced breakdown spectrometry (LIBS) was carried out to detect the silver element in silver jewelry samples. One Nd:YAG was adopted in the experiment to generate two pulses which were set in an orthogonal configuration. The results show that, for double-laser LIBS, average diameter (3μm) of craters on the sample surface is much smaller and the intensity of silver emission signals are magnified by a factor of 40 compared with the single-pulse LIBS. Due to the superiority in high sensitivity and low energy consumption, double-pulse LIBS presents a bright application prospect in rapid on-site undamaged analysis of precious metal jewelry.

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Off-resonance effects in surface nuclear magnetic resonance

Geophysics ◽

10.1190/1.3535414 ◽

2011 ◽

Vol 76 (2) ◽

pp. G1-G12 ◽

Cited By ~ 33

Author(s):

Jan O. Walbrecker ◽

Marian Hertrich ◽

Alan G. Green

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Water Content ◽

Resonance Condition ◽

Single Pulse ◽

Double Pulse ◽

Resonance Effects ◽

Frequency Offsets ◽

Pulse Surface ◽

Nuclear Magnetic

Surface nuclear magnetic resonance (NMR) is a noninvasive geophysical tool used to investigate groundwater reservoirs. The relevant physical process in surface NMR is the nuclear spin of hydrogen protons in liquid water. Standard single-pulse surface NMR experiments provide estimates of water content in the shallow subsurface. Under favorable conditions, pore-structure and even hydraulic-conductivity information can be extracted from double-pulse surface NMR data. One crucial issue in surface NMR experiments is the resonance condition: the frequency of the excitation field should closely match the Larmor frequency of the protons, which is controlled by the local magnitude of the earth’s magnetic field. Although the earth’s field can be measured accurately by an on-site magnetometer, several effects impede perfect matching of the frequencies. These include temporal variations of the earth’s field, instrumental imperfections, and the magnetic susceptibility of the underlying rocks. We assess the impact of violating the resonance condition on surface NMR experiments. Our investigation involves numerical simulations and measurements using a sample-scale earth-field NMR device and a surface NMR acquisition system. For frequency offsets up to 5 Hz, we find that relatively standard single-pulse surface NMR recording procedures are likely to produce reliable water-content estimates as long as the pulse moments are small to moderate or the aquifer is relatively deep. If strong pulse moments are required or shallow aquifers are probed, off-resonance conditions can lead to anomalous increases in recorded amplitudes that can be mistakenly interpreted in terms of deepwater occurrences. Double-pulse surface NMR experiments are particularly sensitive to off-resonance effects, such that the results may be highly biased even for the small-frequency offsets commonly encountered in field situations.

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Single-Pulse Low-Energy-Driven Transient Inversion X-Ray Lasers

IEEE Journal of Selected Topics in Quantum Electronics ◽

10.1109/jstqe.2004.837712 ◽

2004 ◽

Vol 10 (6) ◽

pp. 1368-1372 ◽

Cited By ~ 5

Author(s):

K.A. Janulewicz ◽

G. Priebe ◽

J. Tummler ◽

P.V. Nickles

Keyword(s):

Single Pulse ◽

Low Energy ◽

X Ray

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Laser photonic-reduction stamping for graphene-based micro-supercapacitors ultrafast fabrication

Nature Communications ◽

10.1038/s41467-020-19985-2 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Yongjiu Yuan ◽

Lan Jiang ◽

Xin Li ◽

Pei Zuo ◽

Chenyang Xu ◽

...

Keyword(s):

Energy Density ◽

Three Dimensional ◽

Single Pulse ◽

Laser Pulses ◽

High Energy ◽

Small Time ◽

Low Energy ◽

High Energy Density ◽

Dimensional Structure ◽

Energy Storage Devices

AbstractMicro-supercapacitors are promising miniaturized energy storage devices that have attracted considerable research interest. However, their widespread use is limited by inefficient microfabrication technologies and their low energy density. Here, a flexible, designable micro-supercapacitor can be fabricated by a single pulse laser photonic-reduction stamping. A thousand spatially shaped laser pulses can be generated in one second, and over 30,000 micro-supercapacitors are produced within 10 minutes. The micro-supercapacitor and narrow gaps were dozens of microns and 500 nm, respectively. With the unique three-dimensional structure of laser-induced graphene based electrode, a single micro-supercapacitor exhibits an ultra-high energy density (0.23 Wh cm−3), an ultra-small time constant (0.01 ms), outstanding specific capacitance (128 mF cm−2 and 426.7 F cm−3) and a long-term cyclability. The unique technique is desirable for a broad range of applications, which surmounts current limitations of high-throughput fabrication and low energy density of micro-supercapacitors.

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Dissociated Σ=27 boundaries in silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105187 ◽

1988 ◽

Vol 46 ◽

pp. 624-625

Author(s):

A. Garg ◽

W.A.T. Clark ◽

J.P. Hirth

Keyword(s):

Electron Diffraction ◽

Local Minimum ◽

Boundary Energy ◽

Coincidence Site Lattice ◽

Boundary Plane ◽

Low Energy ◽

Theoretical Understanding ◽

Site Lattice ◽

Kikuchi Pattern ◽

Analysis Techniques

In the last twenty years, a significant amount of work has been done in the theoretical understanding of grain boundaries. The various proposed grain boundary models suggest the existence of coincidence site lattice (CSL) boundaries at specific misorientations where a periodic structure representing a local minimum of energy exists between the two crystals. In general, the boundary energy depends not only upon the density of CSL sites but also upon the boundary plane, so that different facets of the same boundary have different energy. Here we describe TEM observations of the dissociation of a Σ=27 boundary in silicon in order to reduce its surface energy and attain a low energy configuration.The boundary was identified as near CSL Σ=27 {255} having a misorientation of (38.7±0.2)°/[011] by standard Kikuchi pattern, electron diffraction and trace analysis techniques. Although the boundary appeared planar, in the TEM it was found to be dissociated in some regions into a Σ=3 {111} and a Σ=9 {122} boundary, as shown in Fig. 1.

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Transfer optics for high spatial resolution electron spectroscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105394 ◽

1988 ◽

Vol 46 ◽

pp. 666-667

Author(s):

G. G. Hembree ◽

Luo Chuan Hong ◽

P.A. Bennett ◽

J.A. Venables

Keyword(s):

Magnetic Field ◽

Scanning Transmission Electron Microscope ◽

Low Energy ◽

Objective Lens ◽

State University ◽

Arizona State University ◽

Initial Field ◽

Resolution Electron ◽

Scanning Transmission ◽

Low Energy Electrons

A new field emission scanning transmission electron microscope has been constructed for the NSF HREM facility at Arizona State University. The microscope is to be used for studies of surfaces, and incorporates several surface-related features, including provision for analysis of secondary and Auger electrons; these electrons are collected through the objective lens from either side of the sample, using the parallelizing action of the magnetic field. This collimates all the low energy electrons, which spiral in the high magnetic field. Given an initial field Bi∼1T, and a final (parallelizing) field Bf∼0.01T, all electrons emerge into a cone of semi-angle θf≤6°. The main practical problem in the way of using this well collimated beam of low energy (0-2keV) electrons is that it is travelling along the path of the (100keV) probing electron beam. To collect and analyze them, they must be deflected off the beam path with minimal effect on the probe position.

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Performance Evaluation of a Novel Type of Low-Energy Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180525 ◽

1990 ◽

Vol 48 (1) ◽

pp. 354-355

Author(s):

Bertholdand Senftinger ◽

Helmut Liebl

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Field Strength ◽

Numerical Aperture ◽

Low Energy ◽

Energy Electron ◽

High Resolution Imaging ◽

Lens System ◽

Resolution Imaging ◽

Low Energy Electron

During the last few years the investigation of clean and adsorbate-covered solid surfaces as well as thin-film growth and molecular dynamics have given rise to a constant demand for high-resolution imaging microscopy with reflected and diffracted low energy electrons as well as photo-electrons. A recent successful implementation of a UHV low-energy electron microscope by Bauer and Telieps encouraged us to construct such a low energy electron microscope (LEEM) for high-resolution imaging incorporating several novel design features, which is described more detailed elsewhere.The constraint of high field strength at the surface required to keep the aberrations caused by the accelerating field small and high UV photon intensity to get an improved signal-to-noise ratio for photoemission led to the design of a tetrode emission lens system capable of also focusing the UV light at the surface through an integrated Schwarzschild-type objective. Fig. 1 shows an axial section of the emission lens in the LEEM with sample (28) and part of the sample holder (29). The integrated mirror objective (50a, 50b) is used for visual in situ microscopic observation of the sample as well as for UV illumination. The electron optical components and the sample with accelerating field followed by an einzel lens form a tetrode system. In order to keep the field strength high, the sample is separated from the first element of the einzel lens by only 1.6 mm. With a numerical aperture of 0.5 for the Schwarzschild objective the orifice in the first element of the einzel lens has to be about 3.0 mm in diameter. Considering the much smaller distance to the sample one can expect intense distortions of the accelerating field in front of the sample. Because the achievable lateral resolution depends mainly on the quality of the first imaging step, careful investigation of the aberrations caused by the emission lens system had to be done in order to avoid sacrificing high lateral resolution for larger numerical aperture.

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