Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
17
DOSE RESPONSE OF IRRADIATED XRCT RADIOCHROMIC FILM
161
165
EN
M. J.
BUTSON
Department of Medical Physics, Illawarra Cancer Care Centre,
Crown St, Wollongong, N.S.W, 2500, Australia
martin.butson@sesiahs.health.nsw.gov.au
T.
CHEUNG
Dept. of Physics and Materials Science, City University of Hong Kong,
Kowloon Tong, Hong Kong
P. K. N.
YU
Dept. of Physics and Materials Science, City University of Hong Kong,
Kowloon Tong, Hong Kong
H.
ALNAWAF
Center for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, Australia
10.22099/ijsts.2008.2282
– Gafchromic XRCT radiochromic film is a self developing high sensitivity radiochromic film<br />product which can be used for assessment of delivered radiation doses which could match applications such<br />as Computed Tomography (CT) dosimetry. The dose response of Gafchromic XRCT radiochromic film has<br />been measured with reflectance spectrophotometry and desktop scanners. The film automatically changes<br />colour upon irradiation, changing from a yellow to a green/brown colour. Results show a high sensitivity to<br />delivered dose compared to other conventional radiochromic films which is well suited to CT applications<br />where lower applied doses are delivered. Sensitivity is found for this film with a 1cGy applied dose,<br />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 to<br />150kVp x-ray energy range provides a unique enhancement in dosimetric measurement capabilities over<br />currently available dosimetry films for CT applications.
radiochromic film,Gafchromic XRCT,radiation dosimetry,absorption spectra
http://ijsts.shirazu.ac.ir/article_2282.html
http://ijsts.shirazu.ac.ir/article_2282_010aa6b357cd1ef8efe369b2d6e8a932.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
17
STUDY ON IONIZATION EFFECTS PRODUCED BY NEUTRON INTERACTION PRODUCTS IN BNCT FIELD*
167
173
EN
M. R
ESKANDARI
Physics Department, Shiraz University, Shiraz 71454, I. R. of Iran
eskandari@physics.susc.ac.ir
L.
REZAEE
Physics Department, Shiraz University, Shiraz 71454, I. R. of Iran
S.
MOHAMMADI
Physics Department, Payam Nour University, Fariman 93914, I. R. of Iran
mohammadi@pnu.ac.ir
10.22099/ijsts.2008.2283
The ionization effects of charged particles produced in neutron interactions for Boron Neutron<br />Capture Therapy are considered here using SRIM Monte Carlo Code. The estimated values of these effects in<br />a Plexiglas acrylic phantom are shown to agree well with the available experimental values in high Boron<br />concentration areas. As expected, the ionization effects from lithium and alpha particles are significant.<br />However in the low Boron areas, proton ionization makes an important contribution and their effect on<br />healthy tissue should not be ignored.
BNCT,ionization effects,Lithium,Alpha,Protons,healthy tissue
http://ijsts.shirazu.ac.ir/article_2283.html
http://ijsts.shirazu.ac.ir/article_2283_2992ee59058a49d3ec1f22fd0b115f35.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
17
PUSHOUT CROSSED MODULES OF ALGEBROIDS
175
181
EN
M.
ALP
Dumlupinar University, Art and Science Faculty, Mathematics Department, Turkey
malp@dumlupinar.edu.tr
10.22099/ijsts.2008.2284
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.
Crossed module,algebroids,pullback,action,pushout
http://ijsts.shirazu.ac.ir/article_2284.html
http://ijsts.shirazu.ac.ir/article_2284_14eb922aae297750638a9f7e9c90e684.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
17
ON THE SYNCHRONIZATION OF COUPLED CHAOTIC SYSTEMS WITH ZERO LYAPUNOV EXPONENTS
183
190
EN
G. H.
ERJAEE
Mathematics Department, College of Sciences, Shiraz University, Shiraz, I. R. of Iran
erjaee@shirazu.ac.ir
10.22099/ijsts.2008.2285
The threshold of weak and strong synchronization in a coupled chaotic Gaussian map is<br />demonstrated by using the Pyragas’ terminology. However, Vieira and Lichtenberg have shown that the<br />Pyragas’ criteria for weak and strong synchronization cannot be used for all chaotic systems. In this article<br />we demonstrated some interesting synchronization behavior of two coupled chaotic systems with some zero<br />and negative Lyapunov exponents. In such cases the various synchronization behaviors may also depend upon<br />the eigenvalues of a system obtained by subtracting two chaotic systems.
http://ijsts.shirazu.ac.ir/article_2285.html
http://ijsts.shirazu.ac.ir/article_2285_30d30fad73f731c41f748e54c0261bbd.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
06
POSITIVE LAGRANGE POLYNOMIALS
191
195
EN
S. M. M.
ZEKAVAT
Department of Mathematics, School of Science, Shiraz University, Shiraz, I. R. of Iran
zekavat@susc.ac.ir
SH.
KHOSHDEL
Department of Mathematics, School of Science, Shiraz University, Shiraz, I. R. of Iran
10.22099/ijsts.2008.2286
In this paper we demonstrate the existence of a set of polynomials Pi , 1 i n , which are<br />positive semi-definite on an interval [a , b] and satisfy, partially, the conditions of polynomials found in the<br />Lagrange interpolation process. In other words, if a a1 an b is a given finite sequence of real<br />numbers, then Pi (a j ) ij (ij is the Kronecker delta symbol ) ; moreover, the sum of Pi 's is identically 1.
Positive polynomials,Lagrange polynomials
http://ijsts.shirazu.ac.ir/article_2286.html
http://ijsts.shirazu.ac.ir/article_2286_17b9ff0f43b4590360384f1e66b815b0.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
01
TRANSITIVITY OF -RELATION ON HYPERMODULES
197
205
EN
S. M
ANVARIYEH
1Department of Mathematics, Yazd University, Yazd, I. R. of Iran
anvariyeh@yazduni.ac.ir
S.
MIRVAKILI
Department of Mathematics, Payame-Noor University, Yazd, I. R. of Iran
B.
DAVVAZ
Department of Mathematics, Yazd University, Yazd, I. R. of Iran
10.22099/ijsts.2008.2287
¡V In this paper we consider a strongly regular relation ƒá on hypermodules so that the quotient is a<br />module (with abelian group) over a fundamental commutative ring. Also, we state necessary and sufficient<br />conditions so that the relation ƒá is transitive, and finally we prove that ƒá is transitive on hypermodules.
– Hypermodule,hyperring,strongly regular relation,fundamental relation
http://ijsts.shirazu.ac.ir/article_2287.html
http://ijsts.shirazu.ac.ir/article_2287_ebb4df6e3c31aabc39cf04e10695719b.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
01
EFFECT OF THE EXTRINSIC AND TEMPORAL CARRIERS ON RADIATIVE RECOMBINATION OF III-NITRIDE NANOSTRUCTURES
207
213
EN
M.
ESMAEILI
1Department of Basic Science, Islamic Azad University, Damghan Branch, Damghan, I. R. of Iran
moresm@walla.com
H.
HARATIZADEH
Department of Physics, Shahrood University of Technology, 3619995161, P.O. Box 316, Shahrood, I. R. of Iran
M.
GHOLAMI
Department of Basic Science, Islamic Azad University, Damghan Branch, Damghan, I. R. of Iran
B.
MONEMAR
Department of Physics, Chemistry and Biology, Linkoping University, SE-581 581 83 Linkoping, Sweden
10.22099/ijsts.2008.2288
Due to many important applications, the group III-Nitride semiconductors have recently attracted<br />remarkable 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<br />(PL) and time-resolved PL measurements. Extrinsic carriers come from Si doping in the barriers, while<br />temporal carriers originate when the samples are excited by laser beam. The emission peaks of MQWs in PL<br />spectra of the undoped and low-doped samples show a shift towards higher energy levels as excitation<br />intensity increases, while the other samples do not exhibit such a phenomenon due to the dominance of the<br />extrinsic carriers. The transient data confirm the results of the PL measurements.
Nanostructures,photoluminescence (PL),GaN/AlGaN multi quantum well,time Resolved PL (TRPL),polarization fields,exciton,III-Nitride semiconductors,quantum well
http://ijsts.shirazu.ac.ir/article_2288.html
http://ijsts.shirazu.ac.ir/article_2288_65f8a229a91f27726e27d06084d393f7.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
01
ON THE SOLVABILITY OF SOME OPERATOR-DIFFERENTIAL EQUATIONS IN COMPLEX DOMAIN
215
219
EN
A. M.
AKHMEDOV
Baku State University, Department of Mechanics and Mathematics,
Z. Khalilov st., 23, P. O. Box Az-1148, Baku, Azerbaijan
ali_akhmedov@hotmail.com
Y. Y.
MUSTAFAYEVA
Baku State University, Department of Mechanics and Mathematics,
Z. Khalilov st., 23, P. O. Box Az-1148, Baku, Azerbaijan
10.22099/ijsts.2008.2289
In the present paper an operator-differential equation of second order in complex domain is<br />considered when the coefficients have singularity of pole type at the point z=0. A theorem of existence of the<br />solution of the equation is proved and the spectral property of the solution is separately investigated when the<br />coefficients are spectral operators.
– Banach algebra,operator-differential equation,spectral operators,Boolean algebra
http://ijsts.shirazu.ac.ir/article_2289.html
http://ijsts.shirazu.ac.ir/article_2289_7978064bea59623a9b77688ae5e5c00f.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
06
CHARACTERIZATION OF A NEW PREPARED Li2B4O7: Mn DOSIMETER FOR γ- IRRADIATION HIGH-DOSE DOSIMETRY
221
226
EN
M.
SHARIFZADEH
Radiation Applications Research School, Nuclear Science &Technology
Research Institute, P.O. Box 11365-3486, Tehran, I. R. of Iran
msharifzadeh@aeoi.org.ir
R.
GORJIFARD
Radiation Applications Research School, Nuclear Science &Technology
Research Institute, P.O. Box 11365-3486, Tehran, I. R. of Iran
10.22099/ijsts.2008.2291
A lithium borate thermoluminescence dosimeter with 0.3 wt% of manganese impurity<br />concentration was prepared for high dose levels in the range of 1-30 kGy for gamma irradiation applications.<br />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.
Dosimetry,Thermoluminescence,dose response,dose rate,glow curve
http://ijsts.shirazu.ac.ir/article_2291.html
http://ijsts.shirazu.ac.ir/article_2291_8f5d0a024271adf84081c7eebcb9b872.pdf
Springer
Iranian Journal of Science and Technology (Sciences)
1028-6276
32
3
2008
09
06
DETERMINATION OF NEUTRON DETECTORS SHIELD USED FOR THE DETECTION OF LANDMINES
227
233
EN
D.
REZAEI OCHBELAGH
Department of Physics, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, I. R. of Iran
ddrezaey@yahoo.com
H.
MIRI HAKIMABAD
Physics Department, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, I. R. of Iran
R.
IZADI NAJAFABADI
Physics Department, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, I. R. of Iran
10.22099/ijsts.2008.2292
As a result of being hydrogenous moderators, several landmine detection methods based on<br />nuclear 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.
MCNP,shielding,Detection,landmine,Am-Be,neutron backscattering,polyethylene,boric acid
http://ijsts.shirazu.ac.ir/article_2292.html
http://ijsts.shirazu.ac.ir/article_2292_b7436b2627122e4793c96a58afe9111d.pdf