THE MAXIMUM ENERGY OF ħω INDUCED BY N+, N2+ AND N3+ IONS

1996 ◽  
Vol 06 (01n02) ◽  
pp. 59-63
Author(s):  
C.C. Hsu ◽  
T.C. Chu ◽  
Y.C. Chang ◽  
H.H. Hsu
Keyword(s):  
Charge State ◽  
Atomic Number ◽  
Maximum Energy ◽  
Target Atom ◽  
X Rays ◽  
X Ray ◽  
Relationship Of ◽  
The Relationship

The continuous X-ray of Be, Ni, and Cd targets induced by N +, N 2+, N 3+ ions were measured at the projectile energies of 50-, 70-, 100-, 150-, and 200-keV. Since the energy of the projectile is so low and the detecting limit of the detector is about one keV, the continuous X-ray would be the X-rays of nuclear and atomic bremsstrahlung (NB, AB). From the result of maximum energy of ħω. the relationship of a maximum energy ħω of below: [Formula: see text] Which indicates that the maximum energy of ħω depends on (-3/5) power of the atomic number of projectile, Zp. and on (-1/3q) power of the atomic number of target atom, Zt, and on the energy of projectile. Where q expresses the number of charge state of the projectile.

scholarly journals On the Thermal Interpretation of Hard X-Ray Bursts from Solar Flares

1974 ◽  
Vol 57 ◽  
pp. 395-412 ◽  
Author(s):  
John C. Brown
Keyword(s):  
Solar Flares ◽  
Thermal Conduction ◽  
Temperature Structure ◽  
X Rays ◽  
X Ray ◽  
Time Variations ◽  
Relationship Of ◽  
First Time ◽  
The Relationship ◽  
Continuous Temperature

The possible validity of thermal bremsstrahlung models of flare hard X-ray bursts is investigated quantitatively. In particular, the problem of rapid thermal conduction in ‘multi-temperature’ models is adequately examined for the first time by using a continuous temperature distribution consistent with the observed X-ray spectrum. This distribution is obtained from a general analytic solution for the temperature structure required to mimick any ‘non-thermal’ spectrum, the method being equally applicable to cosmic sources.It is concluded that the thermal interpretation might extend to X-rays of hundreds of keV, a result with important consequences for flare energetics. The relationship of such a model to observations of X-ray polarization and rapid time variations is also considered.

X-RAY Microanalysis of Selected Coelenterate Statoliths

1985 ◽  
Vol 65 (3) ◽  
pp. 617-627 ◽  
Author(s):  
David M. Chapman
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Atomic Number ◽  
Elemental Analysis ◽  
Energy Dispersive Spectrometer ◽  
X Ray ◽  
Relationship Of ◽  
Micro Analysis ◽  
The Relationship ◽  
Scanning Electron

When scanning electron microscopy became integrated with X-ray micro-analysis, it became an easy matter to localize an object and perform a semi-quantitative elemental analysis of atoms of atomic number 11 or higher using an energy dispersive spectrometer. This technique is used in the present study to determine the chemistry of the statoliths of eight hydromedusae, two scyphomedusae, one cubozoan and a ctenophore with respect to their comparative biomineralization and the relationship of the mineral to their taxonomy.

INTERACTION OF HIGHLY CHARGED Xeq+ (q = 26, 27, 30) IONS WITH MOLYBDENUM SURFACE

2005 ◽  
Vol 19 (15n17) ◽  
pp. 2443-2451 ◽  
Author(s):  
ZHAOYUAN LIU ◽  
HONGQIANG ZHANG ◽  
XIMENG CHEN ◽  
ZHIHU YANG ◽  
JINZHANG XU ◽  
...  
Keyword(s):  
Energy Range ◽  
Charge State ◽  
Incident Energy ◽  
Target Atom ◽  
Simple Explanation ◽  
Electron Configuration ◽  
X Rays ◽  
X Ray ◽  
Initial Charge ◽  
The Difference

Experimental investigation of Molybdenum L-shell X-ray emission is reported in the collision of highly charged Xe q+ (q = 26,27,30) ions with Molybdenum surface in the energy range 400 to 600 keV. Based on the X-ray spectra obtained and by the extrapolation of experimental data to the lower incident energy range, a limit was found for the energy of the incident ions. The influence of initial charge state on X-ray emission from the target L-shell was observed. The difference of the initial charge state and electron configuration of the incident ions may lead to observably different contribution to the target atom vacancy production and L-shell X-rays emission. Based on COB model, a simple explanation was presented to interpret the features of the experimental results.

Contribution of x-ray total reflection to the background intensity in EPMA

1990 ◽  
Vol 48 (2) ◽  
pp. 202-203
Author(s):  
Werner P. Rehbach ◽  
Peter Karduck
Keyword(s):  
Atomic Number ◽  
Target Material ◽  
Total Reflection ◽  
Background Intensity ◽  
X Rays ◽  
Characteristic Radiation ◽  
X Ray

In the EPMA of soft x rays anomalies in the background are found for several elements. In the literature extremely high backgrounds in the region of the OKα line are reported for C, Al, Si, Mo, and Zr. We found the same effect also for Boron (Fig. 1). For small glancing angles θ, the background measured using a LdSte crystal is significantly higher for B compared with BN and C, although the latter are of higher atomic number. It would be expected, that , characteristic radiation missing, the background IB (bremsstrahlung) is proportional Zn by variation of the atomic number of the target material. According to Kramers n has the value of unity, whereas Rao-Sahib and Wittry proposed values between 1.12 and 1.38 , depending on Z, E and Eo. In all cases IB should increase with increasing atomic number Z. The measured values are in discrepancy with the expected ones.

Some of these could also be operated in the energy range above lOMeV for experiments designed to determine at which energy level radioactivity can be induced in the irradiated medium. A linac with a maximum energy of 25 MeV was commissioned for the U.S. Army Natick Research and Development Labora­ tories in 1963. Its beam power was 6.5 kW at an electron energy of 10 MeV, 18 kW at 24 MeV. Assuming 100% efficiency, a 1-kW beam can irradiate 360 kg of product with a dose of 10 kGy/h. The efficiency of electron accelerators is higher than that of gamma sources because the electron beam can be directed at the product, whereas the gamma sources emit radiation in all directions. An efficiency of 50% is a realistic assumption for accelerator facilities. With that and 6.5 kW beam power an accelerator of the type built for the Natick laboratories can process about 1.2t/h at 10 kGy. In Odessa in the former Soviet Union, now in the Ukraine, two 20-kW accelerators with an energy of 1.4 MeV installed next to a grain elevator went into operation in 1983. Each accelerator has the capacity to irradiate 200 t of wheat per hour with a dose of 200 Gy for insect disinfestation. This corresponds to a beam utilization of 56% (9). In France, a facility for electron irradiation of frozen deboned chicken meat commenced operation at Berric near Vannes (Brittany) in late 1986. The purpose of irradiation is to improve the hygienic quality of the meat by destroying salmonella and other disease-causing (pathogenic) microorganisms. The electron beam accelerator is a 7 MeV/10 kW Cassitron built by CGR-MeV (10). An irradiation facility of this type is shown in Figure . Because of their relatively low depth of penetration electron beams cannot be used for the irradiation of animal carcasses, large packages, or other thick materials. However, this difficulty can be overcome by converting the electrons to x-rays. As indicated in Figure 9, this can be done by fitting a water-cooled metal plate to the scanner. Whereas in conventional x-ray tubes the conversion of electron energy to x-ray energy occurs only with an efficiency of about %, much higher efficiencies can be achieved in electron accelerators. The conversion efficiency depends on the material of the converter plate (target) and on the electron energy. Copper converts 5-MeV electrons with about 7% efficiency, 10-MeV electrons with 12% efficiency. A tungsten target can convert 5-MeV electrons with about 20%, 10-MeV electrons with 30% efficiency. (Exact values depend on target thickness.) In contrast to the distinct gamma radiation energy emitted from radionuclides and to the monoenergetic electrons produced by accelerators, the energy spectrum of x-rays is continuous from the value equivalent to the energy of the bombarding electrons to zero. The intensity of this spectrum peaks at about one-tenth of the maximum energy value. The exact location of the intensity peak depends on the thickness of the converter plate and on some other factors. As indicated in Figure

1995 ◽  
pp. 40-40
Keyword(s):  
Electron Beam ◽  
Electron Energy ◽  
Maximum Energy ◽  
Metal Plate ◽  
Beam Power ◽  
X Rays ◽  
X Ray ◽  
Emit Radiation ◽  
Electron Accelerators ◽  
Gamma Sources

scholarly journals Determination of Fe and Zn Accumulation in Leafy Vegetables and Mushrooms Using Energy Dispersive X-Ray Fluorescence Technique

2011 ◽  
Vol 68 (2) ◽  
Author(s):  
Claudia STIHI ◽  
Gabriela BUSUIOC ◽  
Cristiana RADULESCU ◽  
Carmen ELEKES ◽  
Sorin CIULEI
Keyword(s):  
Leafy Vegetables ◽  
Energy Dispersive ◽  
Wild Edible Mushrooms ◽  
X Ray ◽  
Zn Uptake ◽  
Edxrf Technique ◽  
Armillariella Mellea ◽  
Relationship Of ◽  
The Relationship

The aim of this study was to determine the Fe and Zn concentrations in some leafy vegetables (cabbage, spinach, celery and lettuce) and in their growing soil collected from sites with different industrial activity; in fruiting body of wild edible mushrooms (Armillariella mellea) and in their substrate (soil) collected at different distances by a metal smelter, by using energy dispersive X-ray fluorescence (EDXRF) technique. A quantitative evaluation of the relationship of Fe and Zn uptake by the vegetables and mushrooms from soil was made by calculating the coefficient accumulation Ka. The results reveal that lettuce is a accumulator of Fe and Armillariella mellea is a accumulator of Zn.

Synthese und Röntgenstrukturanalyse von KCuGd2Mo4O16 und KCuTb2Mo4O16/Synthesis and X-Ray Analysis of KCuGd2Mo4O16 and KCuTb2Mo4O16

1995 ◽  
Vol 50 (12) ◽  
pp. 1794-1798 ◽  
Author(s):  
Hk. Müller-Buschbaum ◽  
St. Gallinat
Keyword(s):  
Lattice Energy ◽  
Rare Earth Ions ◽  
Monoclinic Symmetry ◽  
X Ray ◽  
Coulomb Term ◽  
Relationship Of ◽  
The Relationship ◽  
Symmetry Space ◽  
Oxidation State Of Copper ◽  
Symmetry Space Group

Single crystals of the so far unknown compounds KCuGd2Mo4O16 (I) and KCuTb2Mo4O16 (II) have been prepared by flux technique. The compounds crystallize with monoclinic symmetry. space group C62h-C2 /c with (I): a = 5.278(2), b = 12.666(5), c = 19.604(14) Å; β = 92.76(6)°; (II): a = 5.259(13), b = 12.616(3), c = 19.556(9) Å, β = 92.93(4)°, Z = 4. Molybdenum exhibits tetrahedral coordination. The surroundings of copper can be described by distorted tetrahedra, capped by two more distant oxygen atoms, and the rare earth ions show a square antiprism. Potassium is inside an irregular polyhedron. The relationship of the structures of (I) and (II) is discussed with respect to the KLnMo2O8 type compounds. Coulomb term calculations of the lattice energy indicate an oxidation state of copper higher than CuI.

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