Detectors based on wide-gap insulating crystals for registration of intensive beams of nuclear, x-ray, and electromagnetic radiation

2005 ◽  
Author(s):  
V. K. Sokolov ◽  
P. G. Kasherininov ◽  
A. N. Lodygin
Keyword(s):  
Electromagnetic Radiation ◽  
X Ray ◽  
Wide Gap

scholarly journals The Hot Universe with XRISM and Athena

2018 ◽  
Vol 14 (S342) ◽  
pp. 29-36
Author(s):  
M. Guainazzi ◽  
M. S. Tashiro
Keyword(s):  
Electromagnetic Radiation ◽  
Large Scale ◽  
Cosmological Evolution ◽  
X Ray ◽  
Hot Gas ◽  
Cosmic Vision ◽  
Esa Cosmic Vision ◽  
The Universe

AbstractX-ray spectroscopy is key to address the theme of “The Hot Universe”, the still poorly understood astrophysical processes driving the cosmological evolution of the baryonic hot gas traceable through its electromagnetic radiation. Two future X-ray observatories: the JAXA-led XRISM (due to launch in the early 2020s), and the ESA Cosmic Vision L-class mission Athena (early 2030s) will provide breakthroughs in our understanding of how and when large-scale hot gas structures formed in the Universe, and in tracking their evolution from the formation epoch to the present day.

Low-temperature route to nanoscale P3N5 hollow spheres

2003 ◽  
Vol 18 (10) ◽  
pp. 2359-2363 ◽  
Author(s):  
Hongzhou Gu ◽  
Yunle Gu ◽  
Zhefeng Li ◽  
Yongcheng Ying ◽  
Yitai Qian
Keyword(s):  
Photoelectron Spectroscopy ◽  
Hollow Spheres ◽  
Molar Ratio ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Influence Of Temperature On ◽  
Wide Gap ◽  
20 Nm ◽  
High Degree

Nanoscale hollow spheres of amorphous phosphorus nitride (P3N5) were synthesized by reacting PCl3 with NaN3 at 150–250 °C. Transmission electron microscope images show that the hollow spheres have a diameter of 150–350 nm, and the thickness of the shell is 20 nm. A very small amount of curly films were also found in the sample prepared at 150 °C. The infrared spectrum indicates a high degree of purity. X-ray photoelectron spectroscopy indicates the presence of P and N, with a molar ratio of 1:1.62 for P:N. Ultraviolet-visible absorption spectroscopy shows an absorption band at 265–315 nm. Under photoluminescent excitation at 230 nm, the P3N5 emits ultraviolet light at 305 nm. With a band gap of 4.28 eV, the products may be a wide gap semiconductor. A possible mechanism and the influence of temperature on the formation of the hollow spheres are also discussed.

scholarly journals Solar X radiation

1965 ◽  
Vol 23 ◽  
pp. 45-52 ◽  
Author(s):  
C. de Jager
Keyword(s):  
Electromagnetic Radiation ◽  
Gamma Rays ◽  
Electronic Transitions ◽  
List Type ◽  
X Rays ◽  
Type Number ◽  
X Ray ◽  
Image Position ◽  
Electron Shells

X-ray bursts are defined as electromagnetic radiation originating from electronic transitions involving the lowest electron shells; gamma rays are of nuclear origin. Solar gamma rays have not yet been discovered.According to the origin we have : 1.Quasi thermal X-rays, emitted by (a) the quiet corona, (b) the activity centers without flares, and (c) the X-ray flares.2.Non-thermal X-ray bursts; these are always associated with flares.The following subdivision is suggested for flare-associated bursts :

scholarly journals Transport of radiation & energetic particles in accretion flows

1986 ◽  
Vol 119 ◽  
pp. 407-408
Author(s):  
R. Cowsik ◽  
M.A. Lee
Keyword(s):  
Electromagnetic Radiation ◽  
Charged Particles ◽  
Energetic Particles ◽  
Compact Objects ◽  
X Ray ◽  
Accretion Flows

The equations describing the transport of suprathermal charged particles and electromagnetic radiation across accretion flows onto compact objects are solved analytically, including the effect of shocks in the flows. These solutions indicate (a) accretion flows with shocks accelerate particles very efficiently upto ultra-relativistic energies. (b) the emergent spectra of electromagnetic radiation from such flows reproduce the observed spectra of quasars from the infrared to the hard X-ray region.

Transport of neutrinos, radiation and energetic particles in accretion flows

1982 ◽  
Vol 383 (1785) ◽  
pp. 409-437 ◽  
Keyword(s):  
Cosmic Rays ◽  
Electromagnetic Radiation ◽  
Gravitational Collapse ◽  
Charged Particles ◽  
Energetic Particles ◽  
Compact Objects ◽  
Red Giants ◽  
X Ray ◽  
Accretion Flows

The equations describing the transport of suprathermal charged particles, electromagnetic radiation and neutrinos across accretion flows onto compact objects are solved analytically, the effects of shocks in the flow being included. These solutions are used in discussing three illustrative astrophysical examples: acceleration of cosmic rays, generation of spectral continua in quasars and the effect of neutrinos during the collapse of supernova precursors. The main results are: ( а ) Accretion flows with shocks accelerate cosmic rays very efficiently up to the highest energies. ( b ) The emergent spectra of electromagnetic radiation from such flows reproduce the observed spectra of quasars from infrared to the hard X-ray region. ( c ) The neutrinos in the collapsing cores of red giants develop a very hard non-thermal tail in their distribution facilitating the rebound of the gravitational collapse leading to the supernovae.

184 EFFECTS OF X-RAY ELECTROMAGNETIC RADIATION ON BOVINE OOCYTE DEVELOPMENT

2010 ◽  
Vol 22 (1) ◽  
pp. 250
Author(s):  
W. E. Snyder ◽  
J. T. Aaltonen ◽  
H. D. Sigal ◽  
N. M. Loskutoff
Keyword(s):  
Electromagnetic Radiation ◽  
High Energy ◽  
X Rays ◽  
Embryo Production ◽  
Chi Square ◽  
X Ray ◽  
Chi Square Test ◽  
Bovine Oocytes ◽  
Experimental Group

This study examined the effects of X-rays on bovine oocytes used for in vitro embryo production. In recent years, airport security has become more stringent and the use of X-ray screening may be required for all items, which could be problematic when transporting oocytes. Ionizing radiation such as X-rays are high-energy particles that can penetrate into the nucleus of a cell and cause single and double-strand breaks in the DNA chain. Oocytes exposed to X-ray radiation may have DNA damage affecting maturation, fertilization, and embryonic development. Bovine ovaries obtained from a local abattoir were used to collect immature oocytes by follicular aspiration. The oocytes were divided into a control group and an experimental group then placed in maturation medium. The oocytes in the experimental group were placed in a hospital X-ray machine with a single exposure of 100 mA, 120 kVp for 0.3 s. This exposure challenged the oocytes with a comparable, calculated amount of mrems equivalent to a single screening from an airport X-ray machine (30 mrems). After X-ray exposure, the experimental group was cultured with the control at 37°C and 5% CO2. After 18 h, cryopreserved bovine sperm were thawed and processed using BoviPure (Nidacon International, Mölndal, Sweden) density gradient centrifugation and the oocytes were inseminated with 1 × 106 sperm in fertilization medium at 37°C and 5% CO2. After 24 h, both groups were transferred to 50-μL droplets of G1 medium (Vitrolife, Göteborg, Sweden) at 37°C and 6% CO2 and both were transferred into G2 medium after 72 h. Development of the oocytes was scored after an additional 72 h. Results were based on 2 criteria: the percent cleaved (presumptive fertilization) and the percent cleaved that developed to morula and blastocyst stages. The results indicated no significant difference in the percentages of oocytes cleaving after insemination for the control and experimental groups (P = 0.403, chi-square test). However, there was a significant increase (P = 0.037, chi-square test) in the percentages of morulae and blastocysts developing in the control (non-irradiated) v. experimental (X-rayed) groups. The outcome of this study cautions on the potential damage caused to bovine oocytes used for embryo production in vitro when exposed to X-ray electromagnetic radiation during routine air transport screening operations. Table 1.

scholarly journals X-Ray Mapping of Wide Gap Brazed Bi-Metallic Composites

2013 ◽  
Vol 19 (S2) ◽  
pp. 1816-1817
Author(s):  
P. Huggett ◽  
R. Wuhrer
Keyword(s):  
X Ray ◽  
Metallic Composites ◽  
Wide Gap

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

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