The photoirradiation of Mn^III(tpp)N₃ (tpp = meso-tetraphenylporphinato) in the fluid solutions of 2-methyltetrahydrofuran at temperatures of 0 to −70 °C causes competitive reactions between the oxidation of the central manganese of the complex to yield Mn^V(tpp)N and the reduction to Mn^II(tpp). The reduction and the oxidation proceed advantageously at 25 °C and at −80 °C respectively.

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In this work, polystyrene (PS)/triphenyl phosphate (TPP) nanocomposites were prepared by suspension polymerization. The TPP dissolved firstly in styrene monomer, and then suspension polymerization was carried out. The results showed that TPP nanoparticles, being about 50 nm spheres, were homogeneously and uniformly dispersed in a PS matrix, which was first reported. Furthermore, the formation mechanism of TPP nanoparticles was simulated by the dissipative particle dynamics (DPD) method. The flame retardance of the PS/TPP nanocomposite was significantly improved, which was attributed to the nanodispersion of TPP particles in the PS matrix.

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Besides the pyrophosphate group, acting as the essential and primary binding function of TPP the N1-atom of the aminopyrimidine component functions as a second and also essential anchor to the protein component. Only if both of the contacts are formed the productive conformation of TPP within the active site of TPP enzymes is realized. A mechanism is proposed, which explains the results of our experiments with TPP-analogs.

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The effect of sodium dodecyl sulfale (SDS) concentration on the efficiency of the photooxidation of Methyl Orange sensitized by tetraphenylporphyrin (TPP) in the surfactant solution was investigated. It was found that the efficiency of the photooxidation is lower above the critical micelle concentration of SDS-TPP mixed solution (cmc_mix) than below the cmc<mix>. By taking into consideration the formation of an oligomer complex between one TPP molecule and several SDS molecules below the cmc<mix>, it was possible to explain the relatively lower efficiency above the cmc<mix> in terms of the lower reactivity between singlet oxygen produced by the excited TPP and methyl orange (MO) in the less polar environment on the micellar surface.

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Manganese(II) tetraphenylporphyrin, Mn^II (tpp) (tpp = meso-tetraphenylporphinato), was afforded by the pyrolysis of Mn^IV(tpp)(OCH₃)₂ at ≈180 °C under 10⁻⁴–10⁻⁵ Torr (1 Torr ≅ 133.3 Pa). The pyrolysis of Mo^VO(tpp)OR (R = CH₃, C₂H₅) in the solid state yielded Mo^IVO(tpp).

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The reconstitution of pyruvate decarboxylase has been studied kinetically in thepresence of several concentrations of thiamine pyrophosphate (TPP) and Mn²⁺. The Km for TPP determined graphically was decreased by increasing Mn²⁺ concentration, while V_max was almost unchanged. The values of Kms for Mn²⁺ and V_max, were affected in mixed manner by the amount of TPP.
The significance of Kms thus determined is discussed and the values are compared to that determined in transketolase.

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Azidomanganese(III) meso-tetraphenylporphyrin, Mn^III (tpp)N₃, in the solid state was pyrolyzed around 236 °C to yield nitridomanganese (V) meso-tetraphenylporphyrin, Mn^V (tpp)N.

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The kinetics of the binding of thiamine pyrophosphate (TPP) to apoenzyme ot partially purified yeast pyruvate decarboxylase [EC 4. 1. 1. 1] have been studied. A quantitative and spectrophotometric determination procedure for the TPP binding step, which is independent of the subsequent coupled alcohol dehydrogenase [EC 1. 1. 1. 1] reaction, has been described.
The binding of TPP to apodecarboxylase occurred rapidly and reached equilibrium after l0min at 25°C when 0.3μ_M TPP was incubated with 100μg of apodecarboxylase in a reaction mixture containing 20m_M Tris-maleate (pH 6.3) and 10m_M MnSO₄. The relative ratio of the rates of TPP binding to apodecarboxylase in the presence of Mn²⁺, Mg²⁺, and Ca²⁺ was 4, 1, and 0.2, respectively. The binding constants for TPP in the oresence of Mn²⁺ and Mg²⁺ were 0.5μ_M and 25μ_M, respectively, and those for Mn²⁺ and Mg²⁺ in the presence of 1.2μ_M TPP were 0.29m_M and 2.0m_M, respectively. These results indicalte that the affinity of TPP binding to apodecarboxylase in markedly higher with Mn²⁺ than Mg²⁺. The role of metal ions in the binding is discussed.

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The central metals in the metallotetraphenylporphyrins with axial halo or pseudohalo ligands, Mn^III(tpp)X (tpp = 5,10,15,20-tetraphenylporphinato; X = I, Br, Cl, OAc, NCS), Fe^III(tpp)Cl, Co^III(tpp)Cl, and Mo^VO(tpp)X (X = Br, Cl, F, NCS, N3), in 2-methyltetrahydrofuran are photoreduced with visible light at room temperature to form Mn^II(tpp), Fe^II(tpp), Co^II(tpp), and Mo^IVO(tpp), respectively.

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Inhibitory action of sodium tripolyphosphate (Na-TPP) to P-phages growth was studied. Na-TPP had no phagicidal action, did not prevent adsorption of phage and inhibited for-mation of infected cells. Furthermore, no phase yield occurred when Na-TPP was added within 5 min of infection, but addition after that time resulted in normal phage growth. DNA synthesis of infected cells was blocked by Na-TPP added early in the latent period (within 5 min), but addition after that time failed to block its synthesis. RNA synthesis of infected cells was not affected even when Na-TPP was added at various times in the latent period. Furthermore, 72 per cent of 32P-labeled phage P-1 adsorbed in the medium containing Na-TPP was separated by the blendor treatment, but only 12 per cent was separated when adsorbed in the absence of Na-TPP. These results indicate that Na-TPP inhibits the injection of phage DNA into the host cell.

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We showed that tetra-2-pyridinylpyrazine (TPP) and TPP: cesium (1:1 molar ratio) composite layers had excellent electron injection and transport characteristics in organic light emitting diodes. High luminescence efficiency with low driving voltage was observed in various cathode configurations, suggesting that the TPP layer can efficiently accept electrons from metal and metal oxide cathode layers, and transport and inject electrons into an adjacent organic layer.

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Heat treatment effect of Co(II)-tetraphenylporphyrin (Co-TPP) on the catalytic activity for cathodic reduction of oxygen was studied. The improved catalytic activity of Co-TPP heat-treated at temperatures between 500 and 700°C was found to be due to a remarkable increase in the conductivity and the variation of the electronic states of the central metal ion, resulting from an extension of π-electron system by polymerization.

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The molecular orientation and dynamics of 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPOL) radicals in one-dimensional (1D) nanochannels of the crystal of tris(o-phenylenedioxy)cyclotriphosphazene (TPP) were examined using electron spin resonance (ESR) measurements. TEMPOL radicals in the TPP nanochannels performed rotational diffusion motion not around the principal y axis of the g-tensor, as observed in most cases of TEMPO derivatives, but approximately around the principal z axis with much larger activation energy.

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The niobium(V) complex with tetraphenylporphin having OH⁻ as an auxilliay ligand exists as a dimeric complex, [Nb₂(tpp)₂O₃] at a total concentration >10^−4.5 mol dm⁻³, and reacts with an aliphatic or aromatic polyhydroxy compound to form a monomeric complex containing chelate rings by coordination of the deprotonated species, and to cause an appreciable UV-Vis spectral change. In contrast to phenylboronic acid (PBA), the reactivity of [Nb₂(tpp)₂O₃] is independent of pH at least between 4 and 8. Aliphatic comounds are more reactive than aromatic compounds in dioxane–water, while the reactivity order is reversed in the two-phase reaction. The sugar selectivity order of [Nb₂(tpp)₂O₃] in dioxane–water (10:1) (sorbose > fructose >> mannose > arabinose, galactose > glucose) is appreciably different from that of PBA (fructose > sorbose >> arabinose > galactose > mannose > glucose). This may be related to the difference in size of the Lewis acidic center.

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Mo^VO(tpp)Br (tpp = meso-tetraphenylporphinato) is reduced by superoxide ion, O₂⁻, to Mo^IVO(tpp) in 1%(v/v) DMSO–CH₂Cl₂ medium at 25 °C via an intermediate. The intermediate is suggested to be a dioxygen complex and stably exists in the solution at −72 °C. The oxidation state of the central molybdenum in the intermediate complex reversibly changes with temperature between 4+ at −80 °C and 5+ at 0 °C.

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The two methods gave successfully the interfacial absorption spectra. The capillary plate method seems superior to the other in the simplicity of device, the stability of the interface and the reproducibility. The detection limit in this method can be improved by the use of multiple plates. The fraction of interface in a liquid-liquid system can be evaluated in terms of the specific interfacial area, a. The specific interfacial area for the stir cell is determined by the diameter of droplets, d, through the equation of a=6/d, which yields 67cm-1 for the present system. On the other hand, the specific interfacial area for the capillary plate is determined solely by the thickness of the organic phase with the equation of a=2/1, which affords 20cm-1 for the present case.
Though the value of a of the optical stir cell is larger than the other, the spectrum observed in the stir cell method is seriously interfered with by refraction at the toluene droplet surface.
Further investigations on the interfacial reactions, including protonation and metal complex formation, are in progress in which the Teflon capillary plate method is being used.

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This is the first report of the reaction of the superoxide ion (O₂^-) with chloro-5, 10, 15, 20-tetraphenylporphyrinatochromium (III), Cr (III) (TPP) Cl, in dimethyl sulfoxide (DMSO) to give the superoxide adduct Cr (III) (TPP) (O₂^-) Cl.

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This paper briefly outlines the evolution to date of the Trans-Pacific Partnership (TPP) and its potential strategic importance as a building block for eventual establishment of the Free Trade Area of the Asia Pacific (FTAAP). It then assesses the progress of the TPP initiative under four headings: as an FTA; as a region-wide agreement superimposed on an existing network of bilateral and plurilateral agreements among its members; as an instrument of United States’ re-engagement with East Asia; and as a “building block” for the FTAAP. The paper concludes with a discussion of the significance of the TPP for Japan.

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Cobalt, nickel, copper, and oxidovanadium(2+) could be incorporated into nonpolar tetraphenyl porphyrin by using feed materials as metal sulfate, nitrate, and chloride salts and reaction in high-temperature water (423 to 673 K). Yields of metalloporphyrins increased to 94% at 673 K, which indicates that the dissolution of porphyrin and reaction of the metal salts are enhanced in high-temperature water.

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