Promoting entrepreneurship in agriculture in the Eastern Cape:
- Authors: Antrobus, Geoffrey G , Fraser, Gavin C G
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143067 , vital:38198 , DOI: 10.1080/03031853.1994.9524779
- Description: Selected cases in developing entrepreneurship in small-scale subsistence and commercial agriculture in the Eastern Cape are examined, including the provision of marketing facilities, the training programme of the Africa Cooperative Action Trust (ACAT) in Ciskei, government sponsored irrigation projects and the farmer support programme. An attempt is made to draw general conclusions about the necessary ingredients for successful entrepreneurship and the formulation of proposals for further promoting entrepreneurship in agriculture in South Africa.
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Quantifying commercial catch and effort of monkfish Lophius vomerinus and L. vaillanti off Namibia
- Authors: Maartens, Lima , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125786 , vital:35817 , https://doi.10.2989/025776101784528999
- Description: Mark-recapture models do not distinguish how ‘‘deaths’’ accrue to marked animals in the population. If animals lose their tags, then recaptures will be fewer than expected and estimates of survival will be underestimated (Arnason and Mills, 1981; McDonald et al., 2003). Similarly, if the non-reporting rate is unknown and assumed to be negligible, as is the case in some tagging studies (e.g. Cliff et al., 1996, for white sharks Carcharodon carcharias), the probability of capture can be underestimated. The effects of both these problems, inherent in cooperative tagging programmes, lead to too few tagged fish being recovered, with a positive bias on the estimation of population size. These effects are most pronounced when capture probability is low and fewer tags are available for recapture (McDonald et al., 2003).
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Regional patterns in moult and sexual dimorphism of adult Southern Red Bishops Euplectes orix in southern Africa
- Authors: Craig, Adrian J F K , Bonnevie, Bo T , Oschadleus, Hans-Dieter
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449503 , vital:74826 , https://doi.org/10.2989/00306525.2010.488357
- Description: Using the SAFRING database and the Underhill-Zucchini model of primary moult, we analysed the timing of wing moult in Southern Red Bishops Euplectes orix in relation to sex and geographical region. Birds from the winter rainfall region in the south-western sector of the Western Cape start the annual moult more than two months before any other population, but there were no significant differences in starting date within the summer rainfall region. There were striking differences in the estimates of moult duration (62–114 d), which did not follow a consistent pattern in relation to sex or geography; annual variation within a region may be an additional factor. Throughout southern Africa, both sexes showed a trend for longer-winged birds to take more time to complete their moult. We suggest that sex, geographical area and possible annual environmental variations may all influence the timing of moult in local populations. In this sexually dimorphic species, males are consistently longer-winged and heavier than females.
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Relative feather mass indices: are feather masses needed to estimate the percentage of new feather mass grown for moult regression models?
- Authors: Bonnevie, Bo T
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448313 , vital:74721 , https://doi.org/10.2989/00306525.2010.455820
- Description: During the moult of primary wing feathers in birds it is likely that new feather material is being produced at an approximately constant rate if the energetic requirements of the birds are met. In moult regression analyses it is, therefore, desirable to transform moult measurements into a variable based on the amount of new feather material produced because of its linear properties. This can be achieved if the mass of each primary feather is known, and used as a weighting factor in a moult index. These primary feather masses would have to be known for every species being analysed. As an alternative, it is here tested if feather mass indices may be sufficient replacements for species-specific feather masses. Thirty-five species of birds with known primary feather masses were divided into four wing-shape groups, and a feather mass index was built for each group. Within each group, comparisons were made between estimates of moult parameters using the moult index with those using the known primary feather masses. Within groups there were no significant differences between any of the moult estimates.
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Remarkable sensitivity for detection of bisphenol A on a gold electrode modified with nickel tetraamino phthalocyanine containing Ni–O–Ni bridges
- Authors: Chauke, Vongani , Matemadombo, Fungisai , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261280 , vital:53380 , xlink:href="https://doi.org/10.1016/j.jhazmat.2010.01.061"
- Description: This work reports the electrocatalysis of bisphenol A on Ni(II) tetraamino metallophthalocyanine (NiTAPc) polymer modified gold electrode containing Ni–O–Ni bridges (represented as Ni(OH)TAPc). The Ni(II)TAPc films were electro-transformed in 0.1 mol L−1 NaOH aqueous solution to form ‘O–Ni–O oxo bridges’, forming poly-n-Ni(OH)TAPc (where n is the number of polymerising scans). poly-30-Ni(OH)TAPc, poly-50-Ni(OH)TAPc, poly-70-Ni(OH)TAPc and poly-90-Ni(OH)TAPc films were investigated. The polymeric films were characterised by electrochemical impedance spectroscopy and the charge transfer resistance (RCT) values increased with film thickness. The best catalytic activity for the detection of bisphenol A was on poly-70-Ni(OH)TAPc. Electrode resistance to passivation improved with polymer thickness. The electrocatalytic behaviour of bisphenol A was compared to that of p-nitrophenol in terms of electrode passivation and regeneration. The latter was found to passivate the electrode less than the former. The poly-70-Ni(OH)TAPc modified electrode could reliably detect bisphenol A in a concentration range of 7 × 10−4 to 3 × 10−2 mol L−1 with a limit of detection of 3.68 × 10−9 mol L−1. The sensitivity was 3.26 × 10−4 A mol−1 L cm−2.
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Reproductive biology of a riverine cyprinid, Labeo umbratus (Teleostei: Cyprinidae), in small South African reservoirs
- Authors: Potts, Warren M , Booth, Anthony J , Hecht, Thomas , Andrew, Timothy G
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125854 , vital:35826 , https://doi.10.2989/16085910509503849
- Description: The reproductive and recruitment characteristics of moggel, Labeo umbratus, populations were examined in four small South African reservoirs. Reproduction, characterised by an extended spawning season, high fecundity, short incubation time and rapid larval development, appears to be ideally suited to the highly variable environment of small reservoirs. Evidence suggested that L. umbratus spawns in the reservoirs. In two reservoirs where samples were conducted monthly, GSI (gonado-somatic index) was positively correlated with both water temperature and day length, whilst the CPUE (catch per unit effort) of juveniles was not related to any environmental variable. The success of moggel spawning appeared to increase when there was early spring and consistent summer rainfall.
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Reproductive seasonality of southern African inshore and estuarine invertebrates–a biogeographic review
- Authors: Hodgson, Alan N
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447415 , vital:74623 , https://doi.org/10.1080/15627020.2010.11657249
- Description: A literature review reveals that reproductive seasonality of less than 1% of South Africa’s inshore marine invertebrates has been studied. Approximately 95% of studies have been on large, long-lived, gonochoristic, iteroparous species, and nearly 50% on molluscs. There is only a weak relationship between biogeographic region and timing of reproduction. Nevertheless, a relatively large proportion of west coast species studied breed in winter, whereas south coast species tend to have breeding peaks in spring/summer, although many nearly always have mature gametes and probably reproduce year-round. East coast species are mainly continuous or summer breeders. The factors that control gametogenesis and trigger spawning are largely unresolved, although temperature and food are thought to be important in many species.
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Sedimentary facies and geomorphic evolution of a blocked‐valley lake: Lake Futululu, northern Kwazulu‐Natal, South Africa
- Authors: Grenfell, Suzanne E , Ellery, William F N , Grenfell, Michael C , Ramsay, Lisa F , Flügel, Tyrel J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126826 , vital:35928 , https://doi.10.1111/j.1365-3091.2009.01141.x
- Description: Blocked-valley lakes are formed when tributaries are impounded by the relatively rapid aggradation of a large river and its floodplain. These features are common in the landscape, and have been identified in the floodplains of the Solimo˜es-Amazon (Brazil) and Fly-Strickland Rivers (Papua New Guinea), for example, but their inaccessibility has resulted in studies being limited to remotely sensed image analysis. This paper documents the sedimentology and geomorphic evolution of a blocked-valley lake, Lake Futululu on the Mfolozi River floodplain margin, in South Africa, while also offering a context for the formation of lakes and wetlands at tributary junctions. The study combines aerial photography, elevation data from orthophotographs and field survey, and longitudinal sedimentology determined from a series of cores, which were sub-sampled for organic content and particle size analysis. Radiocarbon dating was used to gauge the rate and timing of peat accumulation. Results indicate that following the last glacial maximum, rising sea-levels caused aggradation of the Mfolozi River floodplain. By 3980 years bp, aggradation on the floodplain had impounded the Futululu drainage line, creating conditions suitable for peat formation, which has since occurred at a constant average rate of 0Æ13 cm year)1. Continued aggradation on the Mfolozi River floodplain has raised the base level of the Futululu drainage line, resulting in a series of backstepping sedimentary facies with fluvially derived sand and silt episodically prograding over lacustrine peat deposits. Blocked-valley lakes form where the trunk river has a much larger sediment load and catchment than the tributary stream. Similarly, when the relative difference in sediment loads is less, palustrine wetlands, rather than lakes, may be the result. In contrast, where tributaries drain a steep, well-connected catchment, they may impound much larger trunk rivers, creating lakes or wetlands upstream.
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Semi-submersible rigs: a vector transporting entire marine communities around the world
- Authors: Wanless, Ross M , Scott, Sue , Sauer, Warwick H H , Andrew, Timothy G , Glass, James P , Godfrey, Brian , Griffiths, Charles , Yeld, Eleanor
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126920 , vital:35935 , https://doi.10.1007/s10530-009-9666-2
- Description: A virtually intact subtropical reef community (14 phyla, 40 families and 62 non-native taxa) was associated with a rig under tow from Brazil that became stranded on the remote island of Tristan da Cunha. This exposes rigs as a significant vector spreading alien marine organisms, and includes the first records of free-swimming marine finfish populations becoming established after unintentional movement. With relatively trivial effort, a pre-tow clean would have obviated the need to salvage and dispose of the rig (undertaken largely to address concerns about invasive species), at a cost of *US$20 million. Our findings show that towing biofouled structures across biogeographic boundaries present unexcelled opportunities for invasion to a wide diversity of marine species. Better control and management of this vector is required urgently. Simultaneous, unintentional introductions of viable populations of multiple marine organisms are rare events, and we develop a basic framework for rapid assessment of invasion risks.
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Shark fishing effort and catch of the ragged-tooth shark Carcharias taurus in the South African competitive shore-angling fishery
- Authors: Dicken, Matthew L , Booth, Anthony J , Smale, Malcolm J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126944 , vital:35937 , https://doi.10.2989/18142320609504209
- Description: In South Africa, Carcharias taurus is commonly known as the ragged-tooth shark or raggie. The species is also referred to as the sand-tiger shark in North America and as the grey-nurse shark in Australia. It is a long-lived species with an estimated longevity of up to 40 years (Goldman 2002). Female sharks reach sexual maturity at approximately 10 years (Goldman 2002), and they exhibit a biennial reproductive cycle (Branstetter and Musick 1994, Lucifora et al. 2002, G Cliff, Natal Sharks Board, unpublished data). Intra-uterine cannibalisation results in a maximum fecundity of two pups per litter after a gestation period of approximately 9–12 months (Bass et al. 1975, Gilmore et al. 1983). These life-history characteristics make this species particularly susceptible to overexploitation.
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Site of struggle: the Freedom Park fracas and the divisive legacy of South Africa’s Border War/Liberation Struggle
- Authors: Baines, Gary F
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126954 , vital:35938 , https://doi.10.1080/02533950903076428
- Description: In South Africa, Carcharias taurus is commonly known as the ragged-tooth shark or raggie. The species is also referred to as the sand-tiger shark in North America and as the grey-nurse shark in Australia. It is a long-lived species with an estimated longevity of up to 40 years (Goldman 2002). Female sharks reach sexual maturity at approximately 10 years (Goldman 2002), and they exhibit a biennial reproductive cycle (Branstetter and Musick 1994, Lucifora et al. 2002, G Cliff, Natal Sharks Board, unpublished data). Intra-uterine cannibalisation results in a maximum fecundity of two pups per litter after a gestation period of approximately 9–12 months (Bass et al. 1975, Gilmore et al. 1983). These life-history characteristics make this species particularly susceptible to overexploitation.
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Social learning processes and nature-culture relations of commercial beekeeping practices as small and medium enterprise development in Zimbabwe
- Authors: Masara, Christopher
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/386545 , vital:68150 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122860"
- Description: This paper explores social learning processes and nature-culture relations in a context of transition from traditional to commercial beekeeping in Zimbabwe. The contours of social learning provided by Wals (2007) are used to probe the learning processes in the social interactions shaping an emerging community of commercial beekeepers and their small and medium enterprise development practices. The paper illustrates how the practice of engaging communities in participatory expansive learning research could benefit from more refined tools for understanding the open-ended contours of social learning interactions in relation to nature-culture relations.
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Spatial and seasonal distribution patterns of the ragged-tooth shark Carcharias taurus along the coast of South Africa
- Authors: Dicken, Matthew L , Booth, Anthony J , Smale, Malcolm J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127008 , vital:35943 , https://doi.10.2989/18142320609504210
- Description: Off South Africa, the ragged-tooth shark Carcharias Taurus has been occasionally reported from the West Coast, but it is more commonly found along the East and South coasts from Cape Town to northern KwaZulu-Natal (KZN) (Bass et al. 1975, Smale 2002). Mating is thought to occur off the south coast of KZN from October to late November (G Cliff, Natal Sharks Board, unpublished data). Pregnant females then move northward to spend the early part of their gestation in the warmer waters of northern KZN and possibly southern Moçambique. During July and August, the near-term pregnant females begin to move southwards towards the cooler waters of the Eastern Cape (Wallett 1973, Bass et al. 1975, G Cliff, unpublished data), where they give birth from September to November (Smale 2002). After parturition, many of the females migrate back to KZN. The whereabouts of mature males outside of the mating season is unclear. These broadscale distribution and migratory habits for C. taurus have been inferred from limited catch records obtained for only parts of its range along the South African coast.
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Spatial description of hake-directed fishing activity off the west coast of South Africa
- Authors: Fairweather, T P , Booth, Anthony J , Sauer, Warwick H H , Leslie, Rob W
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/127031 , vital:35945 , https://doi.10.2989/18142320609504129
- Description: Historically, the two species of Cape hakes Merluccius capensis and M. paradoxus off South Africa were commercially exploited exclusively by demersal trawling. In 1994, hake-directed demersal longline was introduced on an experimental basis, and in 1998 was initiated as a commercial fishing sector. The effect of a combined fleet composed of both trawlers and longliners on the Cape hake resource is not fully understood. Analysis of fishing intensity and catch-rate data revealed that the highest catch rates were found around the 400m and 500m isobaths for the trawl and longline fisheries respectively. Catch rates from both fishing sectors were also noted to be higher over sediments with a sand component. Differences between areas of the highest fishing intensity and highest catch rates were noted. In addition to other factors, it is suggested that a ‘friction of distance’ effect applies — vessels will trade-off higher catch rates with the increased costs associated with fishing in deeper waters.
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Spectroscopic behavior of cationic metallophthalocyanines in the presence of anionic quantum dots
- Authors: Idowu, Mopelola , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/262699 , vital:53545 , xlink:href="https://doi.org/10.1016/j.saa.2009.10.050"
- Description: The interactions and spectroscopic properties between cationic zinc phthalocyanine derivatives (peripherally and non-peripherally tetrasubstituted and peripherally octa substituted with 2-diethylmethylaminoethylsulfanyl (βTZnPc, αTZnPc and βOZnPc)) and CdTe core quantum dots (QDs) capped with mercaptopropionic acid or thioglycolic acid (represented as CdTe@MPA and CdTe@TGA, respectively) have been studied in methanol:water mixture. Strong coupling of MPcs was deduced from the interaction since the UV–vis spectroscopic studies of the ground state complex formed on mixing both components showed loss of the phthalocyanine monomeric band with the formation of a dimeric band (spectrum of aggregated species). The dimerization constants were of the order of 104 M−1.
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Spectroscopic studies of nanostructures of negatively charged free base porphyrin and positively charged tin porphyrins
- Authors: George, Reama C , Egharevba, Gabriel O , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261661 , vital:53432 , xlink:href="https://doi.org/10.1016/j.poly.2010.01.028"
- Description: Spectroscopic studies were carried out on the homoaggregates of negatively charged free base meso-tetraphenylsulfonated porphyrin ([H2TPPS4]4−) and heteroaggregates of a mixture of protonated ([H4TPPS4]2−) and tin meso-tetra (N-methyl-4-pyridyl) porphyrin ([SnTMPyP]4+). The spectroscopic studies were done to determine the optimal conditions required for the fabrication of porphyrin nanorods by ionic self assembly of two oppositely charged porphyrins. In addition, the various spectral changes of [H4TPPS4]2− with concurrent change in pH and concentration are also investigated. In acid media at pH more than 3, and at concentrations less than 1 × 10−5 M, [H4TPPS4]2− molecules form J aggregates. A mixture of [H4TPPS4]2− and [SnTMPyP]4+ forms heteroaggregates of the J type in acid media. At pH’s 2 to 3, the optimum ratio for the formation of J aggregates is 3:1 and for pH 1, the optimum ratio is 2:1. Transmission electron microscope images of the nanostructures formed show that they are of cylindrical shape.
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Swelling, erosion and drug release characteristics of salbutamol sulfate from hydroxypropyl methylcellulose-based matrix tablets
- Authors: Chaibva, Faith A , Khamanga, Sandile M , Walker, Roderick B
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184139 , vital:44177 , xlink:href="https://doi.org/10.3109/03639045.2010.488648"
- Description: Background: Hydrophilic matrix formulations are important and simple technologies that are used to manufacture sustained release dosage forms. Method: Hydroxypropyl methylcellulose-based matrix tablets, with and without additives, were manufactured to investigate the rate of hydration, rate of erosion, and rate and mechanism of drug release. Scanning electron microscopy was used to assess changes in the microstructure of the tablets during drug release testing and whether these changes could be related to the rate of drug release from the formulations. Results: The results revealed that the rate of hydration and erosion was dependent on the polymer combination(s) used, which in turn affected the rate and mechanism of drug release from these formulations. It was also apparent that changes in the microstructure of matrix tablets could be related to the different rates of drug release that were observed from the test formulations. Conclusion: The use of scanning electron microscopy provides useful information to further understand drug release mechanisms from matrix tablets.
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Symmetrically and unsymmetrically substituted carboxy phthalocyanines as sensitizers for nanoporous ZnO films
- Authors: Masilela, Nkosiphile , Nombona, Nolwazi , Loewenstein, Thomas , Nyokong, Tebello , Schlettwein, Derck
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/249126 , vital:51780 , xlink:href="https://doi.org/10.1142/S1088424610002793"
- Description: The photoelectroectrochemical studies of water soluble octacarboxylated oxotitanium (OTiOCPc), zinc (ZnOCPC), hydroxyaluminium ((OH)AlOCPc), dihydroxysilicon ((OH)2SiOCPc), hydroxygallium (OHGaOCPc) and low symmetry zinc monocarboxy (ZnMCPc) phthalocyanines were performed. The dyes were adsorbed to nanoporous ZnO electrodeposited in the presence of eosin Y as structure directing agent (SDA) on FTO substrates by refluxing or soaking the films in a solution containing the dye of interest such that a full surface coverage was achieved. High external (IPCE) and internal (APCE) quantum efficiencies of up to 50.6% and 96.7% were achieved for the OTiOCPc complex. There was a lower overall cell efficiency for cells sensitized with phthalocyanines containing hydroxyl as axial ligand ZnO/(OH)2SiOCPc, ZnO/(OH)GaOCPc and (OH)AlOCPc because of strong aggregation on the surface of the electrodes. To further suppress dye aggregation, the zinc complex of a new monocarboxylated phthalocyanine sensitizer with bulky naphtho side groups (ZnMCPc) was employed. Among the studied sensitizers, ZnMCPc gave the highest overall cell efficiency of phthalocyanine electrodeposited on ZnO of η = 0.48%.
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Syntheses and investigation of the effects of position and nature of substituent on the spectral, electrochemical and spectroelectrochemical properties of new cobalt phthalocyanine complexes
- Authors: Akinbulu, Isaac A , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/261677 , vital:53434 , xlink:href="https://doi.org/10.1016/j.poly.2010.01.004"
- Description: The syntheses of new cobalt phthalocyanine (CoPc) complexes, tetra-substituted with diethylaminoethanethio at the peripheral (complex 3a) and non-peripheral (complex 3b) positions, and with benzylmercapto at the non-peripheral position (complex 5), are reported. The effects of the nature and position of substituent on the spectral, electrochemical and spectroelectrochemical properties of these complexes are investigated. Solution electrochemistry of complex 3a showed three distinctly resolved redox processes attributed to CoIIIPc−2/CoIIPc−2 (E½ = +0.64 V versus Ag|AgCl), CoIIPc−2/CoIPc−2 (E½ = −0.24 V versus Ag|AgCl) and CoIPc−2/CoIPc−3 (E½ = −1.26 V versus Ag|AgCl) species. No ring oxidation was observed in complex 3a. Complex 3b showed both ring-based oxidation, attributed to CoIIIPc−1/CoIIIPc−2 species (Ep = +0.86 V versus Ag|AgCl), and ring-based reduction associated with CoIPc−2/CoIPc−3 species (E½ = −1.46 V versus Ag|AgCl), with the normal metal-based redox processes in CoPc complexes: CoIIIPc−2/CoIIPc−2 (Ep = +0.41 V versus Ag|AgCl) and CoIIPc−2/CoIPc−2 (E½ = −0.38 V versus Ag|AgCl). Solution electrochemistry of complex 5 showed the same type and number of species observed in complex 3a: CoIIIPc−2/CoIIPc−2 (Ep = +0.59 V versus Ag|AgCl), CoIIPc−2/CoIPc−2 (E½ = −0.26 V versus Ag|AgCl) and CoIPc−2/CoIPc−3 (E½ = −1.39 V versus Ag|AgCl) species. These processes were confirmed using spectroelectrochemistry.
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Synthesis and electrochemical characterisation of new tantalum (V) alkythio phthalocyanines
- Authors: Chauke, Vongani , Nyokong, Tebello
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/249093 , vital:51777 , xlink:href="https://doi.org/10.1016/j.ica.2010.05.003"
- Description: The synthesis and electrochemical characterisation of octa-pentylthio (4a) and octa-octylthio (4b) – phthalocyaninato tantalum (III) hydroxide are hereby reported. These TaPc complexes absorb in the near infrared region (∼800 nm in dichloromethane). They show good solubility in most common solvents especially non-viscous solvents such as dichloromethane and chloroform. NMR, mass and infrared spectroscopy and elemental analysis confirmed the structures and purity of the synthesised complexes. The cyclic voltammograms (CVs) showed reversible reduction couples and irreversible oxidation peaks. The latter exhibited adsorption behavior. The reduction processes were observed at −0.74 and −1.13 V (versus Ag|AgCl) for 4a, and −0.67, −1.02 and −1.48 V (versus Ag|AgCl) for 4b. Spectroelectrochemistry confirmed one metal reduction, with the rest of the redox processes being centered on the phthalocyanine ring.
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