1 - THE CALCIUM BINDING SITES OF THE BAKERS' YEAST TRANSKETOLASE https://jsciences.ut.ac.ir/article_31510.html 1 The calcium binding sites of Bakers' Yeast Transketolase (TK) was elucidated by estimating the pKa values of the functional groups that bind to calcium. These pKa's were found to be 6.25 and 7.2 relating to the pKa's of the two immidazol moieties of histidine residues on the enzyme. The rate of the binding of calcium to the enzyme was obtained separately as a function of pH. Maximum values were obtained at the pKa's of the immidazol rings of histidine correlating closely with the values obtained by direct titration. The activity rate studies as a function of pH showed that the enzyme, when bound to its cofactors, becomes further activated over and above the regular increasing trend of the pH rate profile at similar pH's which are optimal for calcium binding 0 - 0 0

1 - EFFECTS OF WOOD ON THE GROWTH OF LIGNICOLOUS FRESHWATER FUNGI https://jsciences.ut.ac.ir/article_31511.html 1 The addition of cottonwood and ash sapwood powder to YPSSl2 medium influenced the mycelial growth of 13 species of freshwater lignicolous Ascomycetes and Hyphornycetes. These species fall into three groups with respect to their responses to the presence of leached or non-leached wood powder. Neither wood type showed strong inhibitory effect on the mycelial growth of the species. Leaching did not affect the response of the species to the presence of wood powder 0 - 0 0

1 - A NEW SPECTROPHOTOMETRIC PROCEDURE FOR THE DETERMINATION OF NICKEL (11) USING 6-PHENYL-2,3-DIHYDRO-AS-TRIAZINE-3 –THIONE https://jsciences.ut.ac.ir/article_31512.html 1 A spectrophotometric procedure for the determination of Nickel (??) based on the complex formation with 6-phenyl-2, 3-dihydro-as-triazine-3-thione (PDTT) was developed. A yellow compound forms and is easily extractable by chloroform at pH>6. The mole ratio between Nickel (??) and PDTT is 1:4. The absorbance of the complex obeys Beer's law over the concentration range of 1-7 ug of Ni (??) per ml chloroform. This procedure can be carried out in the presence of many cations and anions without appreciable interference. 0 - 0 0

1 - (II) PREPARATION AND CHARACTERIZATION OF MN (III) COMPLEXES https://jsciences.ut.ac.ir/article_31513.html 1 We have prepared and characterized a few Mn (III) complexes by using a few bidentate and tridentate ligands. Spectra of the manganese (Abstract We have prepared and characterized a few Mn (III) complexes by using a few bidentate and tridentate ligands. Spectra of the manganese (III) ion in a variety of molecular environments are reported . On the basis of solution spectra, some of these complexes seem to be typically distorted 0 - 0 0

1 - PREPARATION AND CRYSTAL STRUCTURE OF CaCl .[OC(NH ) ] https://jsciences.ut.ac.ir/article_31514.html 1 Calcium dichloride tetra urea was prepared by the reaction of calcium chloride with urea in aqueous solution. The crystals are monoclinic, a= 7.633, b= 12.45 1, c= 8.118 ?,? = 113.17, Z = 4, space group P 2,/a. The crystal structure was determined by single crystal X-ray methods and refined to R= 0.041. The calcium atoms are coordinated to four oxygen atoms of urea and to two chloride ions. The coordination polyhedra are distorted octahedral 0 - 0 0

1 - PURINE ALKYLATING AGENTS 2 , 6-DIAMINO-8-HALO ALKYL PURINES (POTENTIAL ANTI - MALARIALS) https://jsciences.ut.ac.ir/article_31515.html 1 Haloalkyl purines i.e. 2,6-diamino-8-(chloromethyl) purine 10; 2, 6-diamino-X- (chloromethyl) purine 17; 2,6-diamino-8-(chloropropylp) urine 18; were synthesized by two distinct but facile methods. The N-alkylating potential of 2, 6-diamino-8- (chloromethyl) purine was investigated. The following products 2,6-diamino-8-(Nbenzyl- N-methyl) purine 11; 2,6-diamino-8-(4-nitro anilinomethyl) purine 13; 2,6- diarnino-8-(piperidino-N-methyl)Purine 14; 2,6-diamino-8-(3,4,5-trimethoxyanilinomethyl) purine 12; of N-alkylation are reported. Antifolate activities obtained for these compounds are also reported. 2,6-diamino-8-(3,4,5-trimethoxyanilinom ethyl) purine demonstrated significant biological activity (ID = 1 x10 ). Most antifols are also antimalarials e.g. trimethoprim and pyrimethamine, and therefore these 8-haloalkyl purines may be effective antimalarials if modified by appropriate reagents 0 - 0 0

1 - SYNTHESIS AND STRUCTURE ELUCIDATION OF 1,2,4-TRIAZINO [4,3-b] 1,2,4-TRIAZINES, 1,2,4-TRIAZINO [3,4-C] 1,2,4-TRIAZINES AND 1,2,4-TRIAZINO [4,3-dl l,2,4-TRIAZINES https://jsciences.ut.ac.ir/article_31516.html 1 0 - 0 0

1 - B IOSTRATIGRAPHY OF SARAKHS (N.E. IRAN) AND NAFTE- SHAHR (N.W. IRAN) SECTIONS https://jsciences.ut.ac.ir/article_31517.html 1 It is the first time that biostratigraphic zonations of calcareous nannoplankton from Maestrichtian to Lower Tertiary deposits of Iran are reported. The required samples from the north-eastem and western parts of the country were selected from the stocks of the National Iranian Oil Company. Taxonomic descriptions were not the main objectives, although a new species and genus are apparently present in the assemblages. The main purpose of this study is to establish the biostratigraphic zonations and correlate them with the universally accepted standard biozones. Both petrographic and scanning electronic microscopes were used in this investigation 0 - 0 0

1 - SOME GENERALIZATIONS OF WEAK CONVERGENCE RESULTS ON MULTIPLE CHANNEL QUEUES IN HEAVY TRAFFIC. https://jsciences.ut.ac.ir/article_31518.html 1 This paper extends certain results of Iglehart and Whitt on multiple channel queues to the case where the inter-arrival times and service times are not necessarily identically distributed. It is shown that the weak convergence results in this case are exactly the same as those obtained by Iglehart and Whitt 0 - 0 0

1 - SOME RESULTS FOR SOLUTION AND FOCAL POINTS OF NONSELFADJOINT SECOND ORDER SYSTEMS https://jsciences.ut.ac.ir/article_31519.html 1 Consider y" (t) + A (t)y (t) + 0, y is a real n-dimensinal vector and A(t) is a real nxn matrix, continuous on some interval. Some positivity properties of solutions and conjugate points of y"(t) + A(t)y (t) = 0 appeared in literature. We prove similar results for focal points 0 - 0 0

1 - ON TE EXISTENCE OF PERIODIC SOLUTION FOR CERTAIN NONLINEAR THIRD ORDER DIFFERENTIAL EQUATIONS https://jsciences.ut.ac.ir/article_31520.html 1 0 - 0 0

1 - ALGEBRAIC INDEPENENCE OF CERTAIN FORMAL POWER SERIES (II) https://jsciences.ut.ac.ir/article_31521.html 1 We shall extend the results of [5] and prove that if f = Z o a x ? Z [[X]] is algebraic over Q (x), where a = 1, ƒ 1 and if ? , ? ,..., ? are p-adic integers, then 1 ? , ? ,..., ? are linkarly independent over Q if and only if (1+x) ,(1+x) ,…,(1+x) are algebraically independent over Q (x) if and only if f , f ,.., f are algebraically independent over Q (x) 0 - 0 0

1 - THE LEFT REGULAR REPRESENTATION OF A COMMUTATIVE SEPARATIVE SEMIGROUP https://jsciences.ut.ac.ir/article_31522.html 1 In this paper, a commutative semigroup will be written as a disjoint union of its cancellative subsemigroups. Based on this fact we will define the left regular representation of a commutative separative semigroup and show that this representation is faithful. Finally concrete examples of commutative separative semigroups, their decompositions and their left regular representations are given. 0 - 0 0

1 - NONDYNAMICAL ANALYSIS OF SPIN AMPLITUDES IN PION-PROTON ELASTIC SCATTERING IN OPTIMAL FORMALISM AT 6.0 GeV/C https://jsciences.ut.ac.ir/article_31523.html 1 Optimal conditions are used in nondynamical formalism to diagonalize the pionproton reaction matrix as much as possible. Invariance laws are imposed to simplify the relationship between observables and bilinear combination of amplitudes. Transverse amplitudes are determined by using measured polarization parameter in xfp elastic scattering at 6.0 GeVIC 0 - 0 0