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Quantification of Metallothioneins in Marine Invertebrates using Differential Pulse Polarography.
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by M. J. Bebianno, W.J. Langston
59-63
DOI: DOI: 10.4152/pea.198901059
by M. M. Delgado Zamarreno, A. Sanchez Perez, J. Hernandez Mendez
65-68
DOI: DOI: 10.4152/pea.198901065
Design and Development of a Flow Through Glucose Reactor
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by J.S. Redinha, Ana M. Oliveira Brett, Jorge L. C. Pereira
69-72
DOI: DOI: 10.4152/pea.198901069
Amperometric Determination of Paraoxon in the Presence of p - Nitrophenol by Flow Injection Analysis.
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by E. Rodriguez Gonzalo, R Carabias Martinez, J. Hernandez Mendez
73-76
DOI: DOI: 10.4152/pea.198901073
Development of Flow Injection Amperometric Monitors for the Determination of Nitrate and other Species
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by Arnold G. Fogg, S. Paul Scullion, Tony E. Edmonds
77-83
DOI: DOI: 10.4152/pea.198901077
by J. E. Simão, H. M.Tavares
85-90
DOI: DOI: 10.4152/pea.198901085
Electron - Transfer Reactions in Vinylidene and Derived Carbyme Complexes of Rhenium
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by Sílvia S. P. R. Almeida, M. Amélia N. D. A. Lemos, Armando J. L. Pombeiro
91-94
DOI: DOI: 10.4152/pea.198901091
The vinylidene complexes trans-[ReCl(=C=CHR)(dppe)2] (R=But, CgH5, C6H4Me-4 or C02Me; dppe = Ph2PCH2CH2PPh2) and the derived carbyne compounds trans-[ReCl(=C-CH2R)(dppe)2]+ undergo, by cyclic voltammetry, in tetrahydrofuran (or acetonitrile), at a Pt electrode, a single-electron reversible oxidation. The electrochemical PL ligand parameter has been estimated for these ligands.
Redox Properties of the Nitrile Complexes trans – [ReCl(NCR)(Ph2PCH2CH2PPh2)2]
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by Maria de Fátima C. Guedes da Silva, Armando J. L. Pombeiro
95-100
DOI: DOI: 10.4152/pea.198901095
The nitrile complexes trans-[ReCl(NCR)(dppe)21 (l;R=alkyl or aryl, dppe = Ph2PCH2CH2PPh2) undergo, in tetrahydrofuran, by cyclic voltammetry and at a Pt electrode, two successive single¬-electron reversible (or quasi-reversible) oxidations and, from the values of the half-wave oxidation potential (E i/2) of the first anodic wave, the electrochemical PL ligand parameter was estimated for the nitrile ligands indicating that they behave as better net electron donors than isocyanides, dinitrogen or carbonyl ligands. For the aromatic nitrile complexes, E i/2 is shown to vary linearly with the Hammett's Op constant of the phenyl substituent.
Redox Properties of Dinitrogen and Mixed Dinitrogen - Isocyanide Complexes of Rhenium with Phosphorous Ligands
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by Maria Fernanda N. N. Carvalho, Armando J. L. Pombeiro
101-106
DOI: DOI: 10.4152/pea.198901101
The electrochemical behaviour of mer-[ReCl(N2)L {P(OMe)3}3] (1,L = CNR or PPh3), trans-[ReCl(N2) {P(OMe)2Ph>4] (2), [ReCl(N2)(CNMe)(PPh3){P(OEt)3}2] (3) and [ReCl(N2)(CNMe)2(PBu2Ph)2] (4) was studied by cyclic voltammetry and controlled potential electrolysis, in tetrahydrofuran (or NCMe), at a Pt electrode.
They undergo a one-electron quasi-reversible oxidation and, by comparing the values of E 1/2 (also with others reported in the literature), the following order of he n - acceptor/o-donor ability was established: CO > CNMe, CNEt, CNBufc > P(OMe)3 >" P(OMe)2Ph > PPh3, Ph2PCH2CH2PPh2 > PMe2Ph.
Redox Potential - Hammett's a or Taft's a* constant Relationships at Ferrocene Derivatives
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by M. Emília N. P. Rodrigues, Armando J. L. Pombeiro
107-112
DOI: DOI: 10.4152/pea.198901107
The redox potential of a variety of ferrocene derivatives has been measured by cyclic voltammetry and correlated linearly with the Hammett's Op or the Taft polar a constant of the substituent; the latter correlation has been recognized for the 3 sp -C ligating substituents.
Spectroelectrochemical Characterization of the Trinuclear [Ru30(02CCH3)6(Pyrazine)3] Clusters
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by Henrique E. Toma, Cecilia Cipriano
113-117
DOI: DOI: 10.4152/pea.198901113
The Influence of Li on the Electrochemical Behaviour of Pure Aluminium
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by J. C. S. Fernandes, M. A. Travassos , E. Leitãoet al.
119-122
DOI: DOI: 10.4152/pea.198901119
Studies of Aluminium Corrosion in Hydrochloric Acid Solution
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by Christopher M. A. Brett
123-126
DOI: DOI: 10.4152/pea.198901123
Electrochemical Behaviour of the Basal Platinum (110) Single Crystal in 0.1 M NaOH
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by E. Morallon, M. Lopez-Atalaya, F. Cases
127-130
DOI: DOI: 10.4152/pea.198901127
Electrochemical Behaviour of the Basal Platinum (110) Single Crystal in 1 M Phosphoric Acid Medium
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by F. Cases, E. Moralion, J. L. Vázquez
131-134
DOI: DOI: 10.4152/pea.198901131
High Temperature Behaviour of Hot Dip (Zn and Al) Steel
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by P. Molera
135-138
DOI: DOI: 10.4152/pea.198901135
The corrosion behaviour of hot dip ( Zn and Al) steel parts heated at diferent temperatures and for varying periods of times has been investigated. Mathematic-statistical treatment of results obtained has been applied. This work show the better protection of steel at high temperature with the aluminized in front of galvanized.
On the Behaviour against Anodic Polarization of Amorphous Alloy, Metglass 2826
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by Juan Davalos Prado
139-142
DOI: DOI: 10.4152/pea.198901139
The evolution oi the polarization anodic curves of amorphous, Metglass 2826 alloys in S042~ , PCn3- dilute solutions, has been studied electrcchemically.
These results show the ranges where they are active (fast metal dissolution) and or passive (formation of protective layers). The mechanisms and interaction parameters through the electrolyte/metal interface have been studied too.
Corrosion in Sea - Coast: Collection and Determination of Marine Atmospheric Chlorides
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by E. Julve
143-147
DOI: DOI: 10.4152/pea.198901143
Electrochemical Behaviour of AISI 304 Stainless Steel in Borate/Cl_ Solution
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by Alda M.P. Simões, Mário G.S. Ferreira
149-153
DOI: DOI: 10.4152/pea.198901149
Pressure and Temperature Effects on the Electrical Conductivities and Walden Products of Tetraethylammonium Iodide in Some Primary and Secondary Alcohols
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by César A.N. Viana, António R.T. Calado
149-166
DOI: DOI: 10.4152/pea.198803149
This work is concerned with pressure and temperature effects on the limiting conductances and Walden products of tetraethylammonium salts in different primary and secondary alcohols.
The results were discussed in terms of both the hydrodynamic model and the transition state theory. . Complementary conclusions were reached by the two sets of parameters resulting from those theories.
