eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31153
ANTIAMOEBIC ACTIVITY OF RIND AND
FLOWERS OF PUNICA GRANATUM LINN
The antiamoebic activity of water soluble fractions of the rind and flowers of
Punicu grunutum has been assessed. The in vitro and in vivo studies, carried out on
a virulent strain of Entamoebu histotyticu, exhibited encouraging results
https://jsciences.ut.ac.ir/article_31153_ae63d20a9a795ff1720e691d6a03586b.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31154
MOLECULAR ANALYSIS OF THE SULFUR
REGULATORY CIRCUIT OF NEUROSPORA
CRASSA
The sulfur regulatory circuit of the filamentous fungus, Neurospora crassa,
consists of a set of unlinked structural genes which encode sulfur catabolic and two
major regulatory genes which govern their expression. The cys-3 regulatory gene
encode a transacting regulatory protein which activates the expression of cys-14 and
ars, whereas the other regulatory genes Scon-l and Scon-2 appear to act in a
negative fashion
https://jsciences.ut.ac.ir/article_31154_855932198b2fe63aa8a88692223c108b.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31155
EFFICIENT PHOSPHOROUS-SULFUR
BOND REDUCTION IN BICYCLIC
THIAPHOSPHORANES WITH
TRI-n-BUTYLTIN HYDRIDE
High yield photolytic reduction of a series of thiaphosphoranes Z p SR to give Z p H
with UV-light-induced tri-n-butyltin hydride through phosphoranyl radical Z p is
described. This reaction is inhibited by a-methylstyrene and initiated by a radical
initiator such as azobisisobutyronitrile
https://jsciences.ut.ac.ir/article_31155_6c00aa9e3719bab443a3ac66f2522b47.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31156
REACTION OF 4-METHYL- 1 2,4-TRIAZOLINE-
3,5-DIONE
WITH
DI AND TRI-SUBSTITUTED STYRENES
S.E. Mallakpour* and G.B. Butler**
2,4,6-Triisopropylstryrene was synthesized in a single step via the Witting
Reaction from the corresponding aldehyde. The reaction of three styrene's
derivatives, 2,6-dimethylstyrene, 2,4,6-trimethylstyrene, and 2,4,6-
triisopropylstyrene with 4-methyl-l,2,4-triazoline-3,5-dion(M eTD) was
investigated. These reactions are instantaneous at room temperature and lead to the
formation of 2: 1 adducts in high yield via double Diels-Alder reactions. In each case
the initially formed 1:l Diels-Alder adduct is extremely reactive, and was not
isolated. It readily undergoes the second Diels- Alder reaction with MeTD. These
2:l adducts wete fully characterized by IR, CNMR(o ff- resonace, INEPT,
multiplicity determination sequence techniques), mass spectra, 'HNMR and
elemental analysis.
https://jsciences.ut.ac.ir/article_31156_28b5f5f0805fec37e34405dcc7718ee7.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31157
EFFECT OF THE NEXT-NEAREST NEIGHBOR
INTERACTION ON THE ORDER-DISORDER
PHASE TRANSITION
In this work, one and two-dimensional lattices are studied theoretically by a
statistical mechanical approach. The nearest and next-nearest neighbor interactions
are both taken into account, and the approximate thermodynamic properties of the
lattices are calculated. The results of our calculations show that: (1) even though the
next-nearest neighbor interaction may have an insignificant effect on the entropy of
either the almost purely ordered or disordered phase, it does have a significant effect
on the entropy of the lattice when the order-disorder transition is taking place. (2) The
next-nearest neighbor interaction broadens the range of temperature on which the
transition occurs. (3) The transition takes place more slowly with respect to temperature,
when the next-nearest neighbor interaction is considered.(4) The average
temperature, at which the transition occurs, shifts to a higher one when there is an
increase in the next-nearest neighbor interaction
https://jsciences.ut.ac.ir/article_31157_111edbe947bd4393bce714a9f51c69f4.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31158
PALYNOLOGICAL STUDY OF PALEOZOIC
SEDIMENTS OF THE CHAL-I-SHEH AREA,
SOUTHWESTERN IRAN
The Paleozoic sediments of the Chal-i-Sheh area in southwestern Iran comprising
of Mila Formation, Ilebek Formation and Faraghan Formation, were studied
palynologically. The samples containing well-preserved palynomorphs include
acritarchs, chitinozoans, scolecodonts and pollenlspores. A palynological zonation
has been established and comparison was made with other parts of the world. Based
on stratigraphic potential of the diagnostic taxa, the Mila Formation is uppermost
Cambrian to lowermost Tremadocian, Ilebek'Formation Tremadocian and the
Faraghan Formation is Lower Permian. Therefore, there is a hiatus within the
Paleozoic sequence of the Chal-i-Sheh area extending from Upper Ordovician into
the Lower Permian. This hiatus possibly coincides with Hercynian Orogeny which
resulted in the emergence of the Zagros Basin and produced extensive erosion.
Comparing palynomorphs of the Paleozoic sediments of Chal-i-Sheh with published
palynological data, reveals that the Zagros Basin has been part of the "Mediterranean
Acritarch Province" during the Lower Ordovician. The presence of gondwanic
palynomorphs within the Faraghan Formation suggests a gondwanic relationship in
the Permian period.
https://jsciences.ut.ac.ir/article_31158_a922b194110acdc01a62fb4793f94a2d.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31159
FIRST REPORT ON PLATINUM-GROUP
MINERALS IN CHROMITITES J%OM
NORTHWESTERN NEYRIZ OPHIOLITE, IRAN
Electron-probe microanalyses and scanning electron microscopy of chrornitites
from some ultramafic members of Neyriz ophiolite indicate that sulifides of platinum-
group minerals (PGMs) occur as solid inclusions in chromite grains. Laurite
with the general formula of (Ru ,Os ,lr ) S , and erlichmanite are the main
identified sulfide phases. The PGMs occur as 4 to 20 microns euhedral to rectangular
inclusions, and seem to be confined to massive chrornitite deposits. The PGMs do not
seem to have exsolved from chromite, it is believed that their crystallization has taken
place prior and/or during the crystallization of this mineral. Some secondary minerals
of rare earth elements (REEs) were also found to fill the micro cracks and fractures
in chromite grains. Semiquantitative analyses reveal the presence of appreciable
amounts of Ce and La along with some minor quantities of Gd, Eu, Pr, and Nd. These
secondary minerals are extremely small and none were found to be larger then 10
microns in diameter. Some base metal alloys (largely made of Ni-Fe), along with
magnetite, ferritechromite, and some olivine and pyroxene silicate inclusions are also
reported.
https://jsciences.ut.ac.ir/article_31159_22f958c7f3d9397d3e0c5208bd9cd982.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31160
ON THE STRUCTURE OF FINITE
PSEUDO- COMPLEMENTS OF
QUADRILATERALS AND THEIR
EMBEDDABILITY
A pseudo-complement of a quadrilateral D of order n, n, > 3, is a non-trivial (n+l)-
regular linear space with n - 3n + 3 points and n + n - 3 lines. We prove that if n > 18
and D has at least one line of size n - 1, or if n > 25 , then the set of lines of D consists of
three lines of size n -1, 6(n - 2) lines of size n - 2, and n - 5n + 6 lines of size n - 3.
Furthermore, if n > 21 and D has at least one line of size n - 1, then D is embeddable in a
unique projective plane of order n. These results improve the results of the author
https://jsciences.ut.ac.ir/article_31160_2404132375eb45510dd90365c0b1caf5.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31161
BIFURCATION OF PERIODIC SOLUTION
FROM AN EQUILIBRIUM POINT IN THE
MULTIPARAMETER CASE
We consider the bifurcation of periodic solutions from an equilibrium point of the
given equation: x =F(x,?) , where x ? R , ? is a vector of real parameters
? , ? , ... , ? and F:R x R ->R has at least second continuous derivations in variables
https://jsciences.ut.ac.ir/article_31161_efa3f2aa7c12cb96e1a6d92c9183494b.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31162
A LOW TEMPERATURE SPECIFIC HEAT
INVESTIGATION OF Cd Mn Se AND Cd Mn S
The specific heat of Cd Mn Se (x = 0.01) and Cd , Mn S (x = 0.026) in the
temperature range of 0.3 - 40K was measured. The measurements were carried out in
different applied magnetic fields (H = 0,10,20, 28KG). The results were analyzed
with a model which includes long range interactions. Calculations based on on
extended version of nearest neighbor pair approximation (including triplets) yielded
a reasonable agreement with the experimental results. This approximation is seen to
provide a good simultaneous description of the specific heat, susceptibility and
magnetization results.
https://jsciences.ut.ac.ir/article_31162_f7c4812ce3eec09ab86f3202523d6679.pdf
eng
University of Tehran
Journal of Sciences, Islamic Republic of Iran
1016-1104
2345-6914
1993-03-01
4
1
31163
DYE JET VELOCITY DISTRIBUTION
MEASUREMENTS USING PHOTOTHERMAL
DEFLECTION SPECTROSCOPY
We demonstrate that photothermal deflection spectroscopy can be used to measure
velocity distributions in dye jets. Such measurements are useful in determining the
quality of flow in dye jets, The quality of jets is very important for a stable and naanow
linewidth operation of dye lasers
https://jsciences.ut.ac.ir/article_31163_5aa205e7138fed606a31996493ecf1ef.pdf