University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 IN VITRO TECHNIQUES COUPLED WITH IRRADIATION FOR SELECTION OF BASMATI RICE MUTANTS BE'ITER ADAPTED TO SALINE ENVIRONMENTS - 31356 EN Journal Article Among different doses of gamma rays, 1.5 kR induced 71.84% callus in Basrnati rice in amodified MS medium and 2% redifferentiation under anon-saline environment, 20% callusing response with 7.5%,2.8% and 2.5% redifferentiation was induced by 2.0 kR at electrical conductivity (EC) of 4,s and 6 dS.m of NaCl respectively, in regeneration medium. A non-irradiated non-saline environment revealed a redifferentiation percentage of 48.28% with a regeneration percentage of 6.9%, in addition to one albino plant, while a non-irradiated saline environment indicated 4% regeneration at 4 dS.m-I EC of NaCl. The results based on these studies are discussed https://jsciences.ut.ac.ir/article_31356_5f795ee135dd0eab5014a56ff3e47df7.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 PURJFICATION OF HIGH MOLECULAR WEIGHT CELLULOLYTIC ENZYMES FROM CELLUWMONAS sp. STRAIN 0 - 31357 EN Journal Article Purification of extra-cellular cellulolytic enzymes from C e l l u l o mssp. strain 0, isolated from forest soil in the north of Iran , was studied by using gel filtration and ion-exchange chromatography. Two endo-glucanases (Endo-I & Endo-II) and one exo-glucanase (Exo-I) were purified to hornogenity . The purified enzymes had molecular weights of about 39.000,70.000 and 90.000 daltons for Endo-I, Endo-II and Exo-I, respectively. Heavy metal ions, like Fe and CU inactivated the enzymes by about 80%, while Zn and CO had no effect on the enzyme activities https://jsciences.ut.ac.ir/article_31357_ff051a2ee798b928b05590a311d0c44b.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 AMPEROMETRIC MICROBIOSENSOR FOR THE DETERMINATION OF CHOLINE - 31358 EN Journal Article The construction and performance of an amperometric microbiosensor for the determination of choline chloride by immobilizing choline oxidase on a cellulose acetate membrane are described. The procedure of choline determination involved the electrochemical detection of enzymatically generated hydrogen peroxide. This microsensor has a linear response between 0.038-0.1 mM choline chloride. The response time is 1-2 minutes. The optimal working conditions for the microsensor were 0.1 M TRIS-HCl, pH = 8 at 30°C https://jsciences.ut.ac.ir/article_31358_8072e512102b794c08f3479a856c0796.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 THE STRUCTURE OF [P$(ReO,) (p-dppm),] [Re0,7,2 - 31359 EN Journal Article Acluster[ pt (Reo )(?-dppm) ][Reo ],2 [dppm=ph Pch ] with oxidaton of [pt Re(CO) ](?-dppm) ][PF ] is prepred . Crystals are triclinic,pl; a= 14.154(4)?, b=14.213(3) ?,c = 20.522(4) ? , a = 78.938(14)?, ?= 75.812(19) ? , ?= 74,957(22) ? ;v = 3828.9(1 5) ? ,z =2 ; Eraf-Noniu CAD4 difhctorneter with Mo- K radiation, ? = 0.71073 ? ; R = 0.069, R = 0.077 for 284 parameters and 5414 reflections with I 3?(I). https://jsciences.ut.ac.ir/article_31359_5b33fd0ecf11b86e2c7cd51c43831a46.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 SYNTHESIS OF 3-ARYLMETHYL-4- THIAZOLIDINE-CARBOXYLIC ACID-2-ONES AND 2-THIONES - 31360 EN Journal Article Barium salts of dibenzylidene cystines 8a-c were obtained from the reaction of Lcystine with benzaldehyde or its derivatives in the presence of barium hydroxide. Their reduction with zinc and hydrochloric acid in methanol yielded the Narylmethylcysteines ?9a-c?. These can, in turn, be converted by esterification into the methyl esters ?10 a-c. ?Reaction of N, N'-carbonyl diimidazole (Im CO) or N, N'- thiocarbonyl diimidazole (Im Cs) with thiols 9a-c and 10a-c gave 3-arylmethy-4- thiazolidine-carboxylic acid-2-ones 3a-c or 2-thiones la-c and their methyl esters 4ac and 2a-c respectively. From the reaction of P S with 3-arylmethyl 4 thiazolidine crespectively acid-2-ones 3a-c and 4a-c the derivatives of 2-thiones 2a-c and la-c were obtained as well https://jsciences.ut.ac.ir/article_31360_583d583ad9ec121c22a60f564d105148.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 SELECTIVE CYCLIZATION OF 2-PROPARGYLTHIO-6-METHYL-PYRIMIDIN- 4(1 H)-ONE TO THIAZOLO [3,2-a] PYRIMIDIN 7-ONE - 31361 EN Journal Article Selective transformation of 2-propargylthio-6-methyl-pyrimidin-4(1H)On e (2) to 3,5-dimethyl-7H-thiazolo [3,2-a] pyrimidin-7-one (3) is performed under the conditionof base catalysis . For elucidation of structure, palladium catalyzed cyclization reaction of (2) was carried out and the structures of the products were assigned (5) and (6). These compounds underwent isomerization to (3) and (4) respectively. From this result, regioselectivity by base catalysis was concluded https://jsciences.ut.ac.ir/article_31361_e6e9d37a0f6a79c25564cade197a8e3c.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 SYNTHESES, ANTIFUNGAL AND ANTIBACTERIAL ACTIVITIES OF SUBSTITUTED 1,2, CTRIMOLES - 31362 EN Journal Article The reaction of readily available 1 -methyl-4-nitropyrrole-2- carboxylic acid (1) with thionyl chloride afforded the corresponding acyl chloride 2. The reaction of compound 2 with thiosemicarbazides yielded 1-(1 -methyl-4-nitrop yrrole-2-carbony1)- thiosemicarbazides (3) which cyclized in basic medium to 5-(1-methyl-4-nitropyrrole- 2-y1)-2,4-dihydro-3H- l,2,4-triazole-3- thione 4. Alkylation and subsequent oxidation of 4 gave 6. The antibacterial and antifungal activities of 6a to 6f against a number of microorganisms were determined. Only compounds 6b and 6c had moderate activity against Aspergilus niger https://jsciences.ut.ac.ir/article_31362_be6534833d70c9056185831475fd92a1.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 BUCHITE FROM FESHARK AREA NORTHEAST ISFAHAN CENTRAL IRAN: A PRELIMINARY STUDY - 31363 EN Journal Article Buchitic glassy rocks appear within the skarn of contact metamorphic aureole of Feshark intrusive complex situated 30 km northeast of Isfahan. Intrusive complex is a multistage intrusion . Noritic gabbro is the first inttrusion which is invaded later on by a granitic melt. Granitic melt has metasomatically altered the gabbro and as a consequence a suite of hybrid rocks like monzogabbro, monzodiorite, and diorite has been formed. A remnant of the original rocks in buchite is biotite bearing feldspathic quartzite or biotite gneissic rock, by fusion of which a granitic melt is forrned. Subsequent supercooling of this melt resulted in glassy buchitic rock. Buchites of Feshark have a glassy, columnar jointed character at bothcontacts with the skarn host rock and a semiglassy character with contorted foliation in the middle part. Buchites are generally very rich in glass, in which minute, very rare, fine crystals of high disordered sanidine, high disordered oligoclase, mullite, orthopyroxene, Fe-Ti oxides, corundum and biotite have been recognized. This mineral assemblage strongly reflects the condition of sanidinite or spurrite-merwinite facies [14] which implies the existence of spurrite-merwinite facies assemblages in skarn host rock. The lack of such an assemblage is interpreted as resulting from the rnetasomatic and retrogressive effect of granite intrusion which reverted very high grade assemblages of spurritemerwinite facies to normal pyroxene hornfels assemblages in host skarn rock. It is probable that the buchitic melt originated in thedeeperpart of the contact metamorphic aureole and was injected into fractures of a higher level https://jsciences.ut.ac.ir/article_31363_d6367279eb84bf8e1e10b10a04bd4292.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 FREE SEMIGROUPS AND IDEMPOTENTS IN T - 31364 EN Journal Article The known theory for an oid T shows how to find a subset T of ?T, which is a compact right topological semigroup [I]. The success of the methods in [2] for obtaining properties of-T has prompted us to see how successful they would be in another context. Thus we find (Theorem 4.8) that T cont ains copies of free semigroups on 2? generators, is an immediate consequence of the stronger result and that it contains a cancellative subsemigroup (Theorem 4.7). Also obtained is a new proof of the known result in [6] that T contains 2? idempotents https://jsciences.ut.ac.ir/article_31364_4a2cde3ca35a41a388c8cc1e19edcbdb.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 NUMERICAL STUDY OF NONLINEAR VOLTERRA INTEGRO-DIFFERENTIAL EQUATIONS BY ADOMIAN'S METHOD† - 31365 EN Journal Article The main purpose of this paper is to consider Adomian's decomposition method in non-linear Volterra integro-differential equations. The advantages of this method, compared with the recent numerical techniques (in particular the implicitly linear collocation methods) , and the convergence of Adomian's method applied to such nonlinear integro-differential equations are discussed. Finally, by using various examples, the accuracy of this method will be shown https://jsciences.ut.ac.ir/article_31365_f5ca5e77fac3302dc36d319d35c7bf65.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 ON THE PERIODIC SOLUTIONS OF A CLASS OF nTH ORDER NONLINEAR DIFFERENTIAL EQUATIONS * - 31366 EN Journal Article The nth order differential equation x + c (t )x + ƒ( t,x) = e(t),n>3 is considered. Using the Leray-Schauder principle, it is shown that under certain conditions on the functions involved, this equation possesses a periodic solution. https://jsciences.ut.ac.ir/article_31366_1687ed4415e7d615460cd56c8093de16.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 A QUARTIC POTENTIAL FOR THE NUCLEONIC QUARKS - 31367 EN Journal Article We assume that each valence quark in a nucleon is in a phenomenological modified harmonic oscillator potential of the form: ( l+yo) (ar +br+cr +dr ), where a, b, c and d are constants and ? is one of the Dirac matrices. Then by making use of a suitable ansatz, the Dirac equation has a very simple solution which is exact. We then have calculated the static properties of the nucleon in the ground state with and without center of mass correction. The results are encouraging. PACS index 12.35 kW and 13.40 fn https://jsciences.ut.ac.ir/article_31367_bb0a0a81b9924f16bc0b81e8e042be09.pdf

University of Tehran Journal of Sciences, Islamic Republic of Iran 1016-1104 9 1 1998 03 01 QUANTUM TUNNELING IN MEDIUMS WITH LINEAR AND NONLINEAR DISSIPATION - 31368 EN Journal Article We have applied the method of integration of the Heisenberg equation of motion proposed by Bender and Dunne, and M. Kamella and M. Razavy to the potential V(q) = v q - µ q with linear and nonlinear dissipation. We concentrate our calculations on the evolution of basis set of Weyl Ordered Operators and calculate the mean position , velocity , the commutation relation [q, p], and the energy of particle. According to our results, the particle which is confined in the well at t= 0, has some oscillations before tunneling. If dissipation is lproportional to velocity it inhibits tunneling but when it is quadric in velocity it facilitates tunneling. Thus, we can continue our cdculation easily for every power of velocity https://jsciences.ut.ac.ir/article_31368_dba76338497e2ebab41d96388c47ff26.pdf