scholarly journals EXPERIMENTAL MEASUEMENTS OF X-RAY ENERGY TRANSPORT ALONG CYLINDRAL CAVITY AXIS

2000 ◽  
Vol 49 (7) ◽  
pp. 1303
Author(s):  
JIANG SHAO-EN ◽  
ZHENG ZHI-JIAN ◽  
CHENG JIN-XIU ◽  
SUN KE-XU ◽  
YANG JIA-MIN ◽  
...  
Keyword(s):  
Energy Transport ◽  
X Ray ◽  
Cavity Axis

Solid-state Thermoelectric Characteristics of NiII, FeII, CoII, and CuII Borohydrides

2021 ◽  
Author(s):  
Isam M. Arafa ◽  
Mazin Y. Shatnawi ◽  
Yousef N. Obeidallah ◽  
Ahmed K. Hijazi ◽  
Yaser A . Yousef
Keyword(s):  
Energy Transport ◽  
Waste Heat ◽  
Mixed Valence ◽  
Small Scale ◽  
X Ray Diffraction ◽  
Promising Candidate ◽  
X Ray ◽  
Cold Pressed ◽  
Thermal Energy Transport ◽  
Body Heat

Abstract Four transition metal borohydrides (MTBHs, MT = Ni, Fe, Co, and Cu) were prepared by sonicating a mixture of the desired MT salt with excess NaBH4 in a nonaqueous DMF/CH3OH media. The process afforded bimetallic (Ni-BH4), trimetallic (Fe-BH4, Co-BH4), and mixed-valence (Cu-H, Cu-BH4) amorphous, ferromagnetic nanoparticles as identified by thermal, ATR-IR, X-Ray diffraction, and magnetic susceptibility techniques. The electrical conductivity (σ) of cold-pressed discs of these MTBHs shows a nonlinear increase while their thermal conductivity (κ) decreases in the temperature range of 303 ≤ T ≤ 373 K. The thermal energy transport occurs through phonon lattice dynamics rather than electronic. The σ/κ ratio shows a nonlinear steep increase from 9.4 to 270 KV-2 in Ni-BH4, while a moderate-weak increase is observed for Fe-BH4, Co-BH4, and Cu-BH4. Accordingly, the corresponding thermoelectric (TE) parameters S, PF, ZT, and η were evaluated. All TE data shows that the bimetallic Ni-BH4 (S, 80 μVK-1; PF, 259 μWm-1K-2; ZT 0.64; η, 2.56%) is a better TE semiconductor than the other three MT-BHs investigated in this study. Our findings show that Ni-BH4 is a promising candidate to exploit low-temperature waste heat from body heat, sunshine, and small domestic devices for small-scale TE applications.

scholarly journals Study of second harmonic emissions for characterization of laser–plasma X-ray sources

1998 ◽  
Vol 16 (2) ◽  
pp. 397-404 ◽  
Author(s):  
A. Giulietti ◽  
C. Beneduce ◽  
T. Ceccotti ◽  
D. Giulietti ◽  
L.A. Gizzi ◽  
...  
Keyword(s):  
Laser Beam ◽  
Transport Process ◽  
Energy Transport ◽  
Laser Light ◽  
Second Harmonic ◽  
Target Position ◽  
Laser Pulses ◽  
Strongly Correlated ◽  
X Ray

An investigation of second harmonic (SH) and X-ray emissions from Al plasmas produced by 3-ns, 1.064-μm laser pulses at 1014 W/cm2 is reported. The SH and X-ray yields are strongly correlated as a function of the target position with respect to the laser beam focus. The SH originates from the underdense coronal plasma and has a filamentary source, while the X-ray source is uniform. The results suggest that, although the X-ray emission is significantly enhanced by the filamentation of the laser light in the corona, there is a smoothing effect in the energy transport process toward the overdense region.

X-ray polarization spectroscopy to study energy transport in ultra-high intensity laser produced plasmas

2009 ◽  
Author(s):  
H. Nishimura ◽  
Y. Inubushi ◽  
Y. Okano ◽  
S. Fujioka ◽  
T. Kai ◽  
...  
Keyword(s):  
High Intensity ◽  
Energy Transport ◽  
Polarization Spectroscopy ◽  
X Ray ◽  
High Intensity Laser ◽  
Intensity Laser

scholarly journals Models of Flaring Loops

1989 ◽  
Vol 104 (1) ◽  
pp. 105-115
Author(s):  
A. Gordon Emslie
Keyword(s):  
Solar Flares ◽  
Energy Transport ◽  
High Energy ◽  
Loop Structure ◽  
Predominant Role ◽  
Release Process ◽  
Flare Loop ◽  
X Ray ◽  
Physical Mechanisms ◽  
High Energy Electrons

AbstractWe review the somewhat questionable concept of an isolated flare loop and the various physical mechanisms believed to be responsible, to some degree, for energy transport within the loop structure. Observational evidence suggests a predominant role for high-energy electrons as an energy transport mechanism, and we explore the consequences of such a scenario in some detail, focusing on radiation signatures in the soft X-ray, hard X-ray, and EUV wavebands, as observed by recent satellite observatories. We find that the predictions of flare loop models are in fact in excellent agreement with these observations, reinforcing both the notion of the loop as a fundamental component of solar flares and the belief that electron acceleration is an integral part of the flare energy release process.

scholarly journals Streaked Spectrometry Using Multilayer X-Ray Interference mirrors to investigate Energy Transport in Laser Plasma Applications

1981 ◽  
Author(s):  
G. L. Stradling ◽  
T. W. Barbee ◽  
B. L. Henke ◽  
E. M. Campbell ◽  
W. C. Mead
Keyword(s):  
Laser Plasma ◽  
Energy Transport ◽  
X Ray ◽  
Plasma Applications

scholarly journals Column Accretion on to White Dwarfs

1983 ◽  
Vol 72 ◽  
pp. 181-197
Author(s):  
A. R. King
Keyword(s):  
Electron Energy ◽  
White Dwarf ◽  
White Dwarfs ◽  
Recent Progress ◽  
Energy Transport ◽  
X Ray

The problem of column accretion on to white dwarfs in the AM Her and DQ Her systems is reviewed. Particular attention is paid to recent progress in explaining the large soft X-ray - EUV fluxes observed in these systems in terms of nonlocal electron energy transport into the white dwarf photosphere.

X-Ray Diagnostics in the Laser-Initiated Fusion Program

1975 ◽  
Vol 19 ◽  
pp. 533-569
Author(s):  
R. P. Godwin
Keyword(s):  
Energy Transport ◽  
Field Measurements ◽  
Electronic Energy ◽  
Exciting Field ◽  
Temperature Plasma ◽  
X Ray ◽  
X Ray Imaging ◽  
Temporal And Spatial ◽  
Plasma Coupling ◽  
Insight Into

The high-density and high-temperature plasma conditions required for successful laser-initiated fusion make x-ray diagnostics a valuable tool in this exciting field. Measurements of the hard x-ray bremsstrahlung continuum emitted from laser targets provide insight into the complex laser-plasma coupling physics and the subsequent electronic energy transport. X-ray techniques are important in the selection and assay of microballoon targets for current compression experiments. X-ray imaging experiments and diffraction spectroscopy of highly stripped atoms can provide information about the symmetry, density and temperature of laser targets. Extremely high temporal and spatial resolution may be required for definitive diagnostic information on compressed targets. While laser-produced plasmas are interesting as possible intense x-ray sources and as a possible means of achieving x-ray lasing, those topics are outside the scope of this review.

scholarly journals Energy transport experiments at Institute of Laser Engineering, Osaka University

1989 ◽  
Vol 7 (3) ◽  
pp. 495-504 ◽  
Author(s):  
K. A. Tanaka ◽  
Y. Kato ◽  
S. Nakai ◽  
H. Shiraga ◽  
T. Yabe ◽  
...  
Keyword(s):  
Energy Transport ◽  
High Efficiency ◽  
Laser Energy ◽  
Rear Side ◽  
X Rays ◽  
Uv Laser ◽  
X Ray ◽  
Characteristic Emission ◽  
Irradiation Energy ◽  
The One

Emissions from the rear side of the targets were temporally resolved by irradiating an ultraviolet (UV) laser on Al and Au thin targets. A difference was clearly observed between the above two targets. Given the fact that absorbed laser energy is converted with a very high efficiency to soft x-rays in a high Z plasma, a characteristic emission peak only observed for Au targets was attributed to the effect of soft x-ray energy transport. The ablation pressures estimated from the emissions indicate that the pressure scaling for Au is close to the one by x-ray radiation rather than by a UV laser. With soft x-ray irradiation, energy transport in A1 foils was also studied. An ablation pressure was estimated by the shock speed.

scholarly journals Correlative study of the emission from flares associated with Sun quakes

2007 ◽  
Vol 3 (S247) ◽  
pp. 99-104
Author(s):  
J. C. Martínez-Oliveros ◽  
A.-C. Donea ◽  
P. S. Cally
Keyword(s):  
Solar Atmosphere ◽  
Solar Flares ◽  
Energy Transport ◽  
Diagnostic Techniques ◽  
The Sun ◽  
X Ray ◽  
Common Features ◽  
Correlative Study ◽  
Multi Wavelength

AbstractMulti-wavelength studies of energetic solar flares with seismic emissions have revealed interesting common features that may help us to identify the correlations of flare signatures from the inner to the outer solar atmosphere and, to develop diagnostic techniques to aid in the sun quake detection. In our study, we make use the relation between the microwave and the hard X-ray emissions associated with such flares to propose a scenario for the ignition of seismic transients from flares. We explore the mechanisms of energy transport to the photosphere, such us back-warming or direct particle impacts.

scholarly journals Damage thresholds for blaze diffraction gratings and grazing incidence optics at an X-ray free-electron laser

2018 ◽  
Vol 25 (1) ◽  
pp. 85-90 ◽  
Author(s):  
Jacek Krzywinski ◽  
Raymond Conley ◽  
Stefan Moeller ◽  
Grzegorz Gwalt ◽  
Frank Siewert ◽  
...  
Keyword(s):  
Free Electron ◽  
Free Electron Laser ◽  
Energy Transport ◽  
Surface Oxidation ◽  
Damage Threshold ◽  
Grazing Incidence ◽  
High Repetition Rate ◽  
Angle Of Incidence ◽  
Or Efficiency ◽  
X Ray

The Linac Coherent Light Source is upgrading its machine to high repetition rate and to extended ranges. Novel coatings, with limited surface oxidation, which are able to work at the carbon edge, are required. In addition, high-resolution soft X-ray monochromators become necessary. One of the big challenges is to design the mirror geometry and the grating profile to have high reflectivity (or efficiency) and at the same time survive the high peak energy of the free-electron laser pulses. For these reasons the experimental damage threshold, at 900 eV, of two platinum-coated gratings with different blazed angles has been investigated. The gratings were tested at 1° grazing incidence. To validate a model for which the damage threshold on the blaze grating can be estimated by calculating the damage threshold of a mirror with an angle of incidence identical to the angle of incidence on the grating plus the blaze angle, tests on Pt-coated substrates have also been performed. The results confirmed the prediction. Uncoated silicon, platinum and SiB3(both deposited on a silicon substrate) were also investigated. In general, the measured damage threshold at grazing incidence is higher than that calculated under the assumption that there is no energy transport from the volume where the photons are absorbed. However, it was found that, for the case of the SiB3coating, the grazing incidence condition did not increase the damage threshold, indicating that the energy transport away from the extinction volume is negligible.

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