DOSE RESPONSE OF IRRADIATED XRCT RADIOCHROMIC FILM
M. J.
BUTSON
Department of Medical Physics, Illawarra Cancer Care Centre,
Crown St, Wollongong, N.S.W, 2500, Australia
author
T.
CHEUNG
Dept. of Physics and Materials Science, City University of Hong Kong,
Kowloon Tong, Hong Kong
author
P. K. N.
YU
Dept. of Physics and Materials Science, City University of Hong Kong,
Kowloon Tong, Hong Kong
author
H.
ALNAWAF
Center for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
author
text
article
2008
eng
– Gafchromic XRCT radiochromic film is a self developing high sensitivity radiochromic filmproduct which can be used for assessment of delivered radiation doses which could match applications suchas Computed Tomography (CT) dosimetry. The dose response of Gafchromic XRCT radiochromic film hasbeen measured with reflectance spectrophotometry and desktop scanners. The film automatically changescolour upon irradiation, changing from a yellow to a green/brown colour. Results show a high sensitivity todelivered dose compared to other conventional radiochromic films which is well suited to CT applicationswhere lower applied doses are delivered. Sensitivity is found for this film with a 1cGy applied dose,producing an approximate net optical density change of 0.3 at 636nm and 0.2 net OD using broad band white light. This high sensitivity combined with its relatively energy independent nature around the 100kVp to150kVp x-ray energy range provides a unique enhancement in dosimetric measurement capabilities overcurrently available dosimetry films for CT applications.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
161
165
http://ijsts.shirazu.ac.ir/article_2282_010aa6b357cd1ef8efe369b2d6e8a932.pdf
dx.doi.org/10.22099/ijsts.2008.2282
STUDY ON IONIZATION EFFECTS PRODUCED BY NEUTRON INTERACTION PRODUCTS IN BNCT FIELD*
M. R
ESKANDARI
Physics Department, Shiraz University, Shiraz 71454, I. R. of Iran
author
L.
REZAEE
Physics Department, Shiraz University, Shiraz 71454, I. R. of Iran
author
S.
MOHAMMADI
Physics Department, Payam Nour University, Fariman 93914, I. R. of Iran
author
text
article
2008
eng
The ionization effects of charged particles produced in neutron interactions for Boron NeutronCapture Therapy are considered here using SRIM Monte Carlo Code. The estimated values of these effects ina Plexiglas acrylic phantom are shown to agree well with the available experimental values in high Boronconcentration areas. As expected, the ionization effects from lithium and alpha particles are significant.However in the low Boron areas, proton ionization makes an important contribution and their effect onhealthy tissue should not be ignored.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
167
173
http://ijsts.shirazu.ac.ir/article_2283_2992ee59058a49d3ec1f22fd0b115f35.pdf
dx.doi.org/10.22099/ijsts.2008.2283
PUSHOUT CROSSED MODULES OF ALGEBROIDS
M.
ALP
Dumlupinar University, Art and Science Faculty, Mathematics Department, Turkey
author
text
article
2008
eng
In this paper, we presented algebroids and crossed modules of algebroids. We also presented pullback crossed module of algebroids and we then define pushout crossed modules of algebroids.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
175
181
http://ijsts.shirazu.ac.ir/article_2284_14eb922aae297750638a9f7e9c90e684.pdf
dx.doi.org/10.22099/ijsts.2008.2284
ON THE SYNCHRONIZATION OF COUPLED CHAOTIC SYSTEMS WITH ZERO LYAPUNOV EXPONENTS
G. H.
ERJAEE
Mathematics Department, College of Sciences, Shiraz University, Shiraz, I. R. of Iran
author
text
article
2008
eng
The threshold of weak and strong synchronization in a coupled chaotic Gaussian map isdemonstrated by using the Pyragas’ terminology. However, Vieira and Lichtenberg have shown that thePyragas’ criteria for weak and strong synchronization cannot be used for all chaotic systems. In this articlewe demonstrated some interesting synchronization behavior of two coupled chaotic systems with some zeroand negative Lyapunov exponents. In such cases the various synchronization behaviors may also depend uponthe eigenvalues of a system obtained by subtracting two chaotic systems.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
183
190
http://ijsts.shirazu.ac.ir/article_2285_30d30fad73f731c41f748e54c0261bbd.pdf
dx.doi.org/10.22099/ijsts.2008.2285
POSITIVE LAGRANGE POLYNOMIALS
S. M. M.
ZEKAVAT
Department of Mathematics, School of Science, Shiraz University, Shiraz, I. R. of Iran
author
SH.
KHOSHDEL
Department of Mathematics, School of Science, Shiraz University, Shiraz, I. R. of Iran
author
text
article
2008
eng
In this paper we demonstrate the existence of a set of polynomials Pi , 1 i n , which arepositive semi-definite on an interval [a , b] and satisfy, partially, the conditions of polynomials found in theLagrange interpolation process. In other words, if a a1 an b is a given finite sequence of realnumbers, then Pi (a j ) ij (ij is the Kronecker delta symbol ) ; moreover, the sum of Pi 's is identically 1.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
191
195
http://ijsts.shirazu.ac.ir/article_2286_17b9ff0f43b4590360384f1e66b815b0.pdf
dx.doi.org/10.22099/ijsts.2008.2286
TRANSITIVITY OF -RELATION ON HYPERMODULES
S. M
ANVARIYEH
1Department of Mathematics, Yazd University, Yazd, I. R. of Iran
author
S.
MIRVAKILI
Department of Mathematics, Payame-Noor University, Yazd, I. R. of Iran
author
B.
DAVVAZ
Department of Mathematics, Yazd University, Yazd, I. R. of Iran
author
text
article
2008
eng
¡V In this paper we consider a strongly regular relation ƒá on hypermodules so that the quotient is amodule (with abelian group) over a fundamental commutative ring. Also, we state necessary and sufficientconditions so that the relation ƒá is transitive, and finally we prove that ƒá is transitive on hypermodules.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
197
205
http://ijsts.shirazu.ac.ir/article_2287_ebb4df6e3c31aabc39cf04e10695719b.pdf
dx.doi.org/10.22099/ijsts.2008.2287
EFFECT OF THE EXTRINSIC AND TEMPORAL CARRIERS ON RADIATIVE RECOMBINATION OF III-NITRIDE NANOSTRUCTURES
M.
ESMAEILI
1Department of Basic Science, Islamic Azad University, Damghan Branch, Damghan, I. R. of Iran
author
H.
HARATIZADEH
Department of Physics, Shahrood University of Technology, 3619995161, P.O. Box 316, Shahrood, I. R. of Iran
author
M.
GHOLAMI
Department of Basic Science, Islamic Azad University, Damghan Branch, Damghan, I. R. of Iran
author
B.
MONEMAR
Department of Physics, Chemistry and Biology, Linkoping University, SE-581 581 83 Linkoping, Sweden
author
text
article
2008
eng
Due to many important applications, the group III-Nitride semiconductors have recently attractedremarkable attention among semiconductor researchers and engineers. In this paper, we report on the impact of extrinsic and temporal carriers on the screening of polarization internal fields. The optical efficiency of GaN/AlGaN multiple quantum well (MQW) nanostructures were studied by means of photoluminescence(PL) and time-resolved PL measurements. Extrinsic carriers come from Si doping in the barriers, whiletemporal carriers originate when the samples are excited by laser beam. The emission peaks of MQWs in PLspectra of the undoped and low-doped samples show a shift towards higher energy levels as excitationintensity increases, while the other samples do not exhibit such a phenomenon due to the dominance of theextrinsic carriers. The transient data confirm the results of the PL measurements.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
207
213
http://ijsts.shirazu.ac.ir/article_2288_65f8a229a91f27726e27d06084d393f7.pdf
dx.doi.org/10.22099/ijsts.2008.2288
ON THE SOLVABILITY OF SOME OPERATOR-DIFFERENTIAL EQUATIONS IN COMPLEX DOMAIN
A. M.
AKHMEDOV
Baku State University, Department of Mechanics and Mathematics,
Z. Khalilov st., 23, P. O. Box Az-1148, Baku, Azerbaijan
author
Y. Y.
MUSTAFAYEVA
Baku State University, Department of Mechanics and Mathematics,
Z. Khalilov st., 23, P. O. Box Az-1148, Baku, Azerbaijan
author
text
article
2008
eng
In the present paper an operator-differential equation of second order in complex domain isconsidered when the coefficients have singularity of pole type at the point z=0. A theorem of existence of thesolution of the equation is proved and the spectral property of the solution is separately investigated when thecoefficients are spectral operators.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
215
219
http://ijsts.shirazu.ac.ir/article_2289_7978064bea59623a9b77688ae5e5c00f.pdf
dx.doi.org/10.22099/ijsts.2008.2289
CHARACTERIZATION OF A NEW PREPARED Li2B4O7: Mn DOSIMETER FOR γ- IRRADIATION HIGH-DOSE DOSIMETRY
M.
SHARIFZADEH
Radiation Applications Research School, Nuclear Science &Technology
Research Institute, P.O. Box 11365-3486, Tehran, I. R. of Iran
author
R.
GORJIFARD
Radiation Applications Research School, Nuclear Science &Technology
Research Institute, P.O. Box 11365-3486, Tehran, I. R. of Iran
author
text
article
2008
eng
A lithium borate thermoluminescence dosimeter with 0.3 wt% of manganese impurityconcentration was prepared for high dose levels in the range of 1-30 kGy for gamma irradiation applications.The TLD reader was used for read out purposes from ambient temperature to about 400°C with a heating rate of 6°C/sec. The pre- and post- irradiation anneal temperature was 300°C for 1.5 and 1 hours respectively. The effects of absorbed dose, dose rate, storage time, as well as the temperature and humidity versus pre- and post-irradiation storage time have been studied. The main glow peak was found to occur at 375°C, and the dosimeter response in the range of 1-30 kGy was linear. No significant fading effect of the dosimetric peak was observed after 8 weeks of storage, and the effects of ambient temperature and humidity were less than ±5% at 95% confidence level.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
221
226
http://ijsts.shirazu.ac.ir/article_2291_8f5d0a024271adf84081c7eebcb9b872.pdf
dx.doi.org/10.22099/ijsts.2008.2291
DETERMINATION OF NEUTRON DETECTORS SHIELD USED FOR THE DETECTION OF LANDMINES
D.
REZAEI OCHBELAGH
Department of Physics, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, I. R. of Iran
author
H.
MIRI HAKIMABAD
Physics Department, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, I. R. of Iran
author
R.
IZADI NAJAFABADI
Physics Department, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, I. R. of Iran
author
text
article
2008
eng
As a result of being hydrogenous moderators, several landmine detection methods based onnuclear techniques have been suggested in recent years. Because of elastic scattering and moderating neutrons from hydrogen atoms in landmines, detection of backscattered neutron shows an anomaly in the reflected thermal neutrons count when a detector scans over a mine. On landmine detection using neutron sources, a detector and its shielding play an important role. In this paper, based on the investigations and calculations performed by MCNP code (Monte Carlo N-Particle transport code), detector shielding materials and their thicknesses have been determined. Therefore, the effects of moderators such as graphite, heavy water, beryllium, polyethylene and boric acid on backscattered neutron flux have been investigated.
Iranian Journal of Science and Technology (Sciences)
Shiraz University
1028-6276
32
v.
3
no.
2008
227
233
http://ijsts.shirazu.ac.ir/article_2292_b7436b2627122e4793c96a58afe9111d.pdf
dx.doi.org/10.22099/ijsts.2008.2292