Sepiolite is a clay mineral, a complex magnesium silicate, a typical formula for which is (OH2)4(OH)4Mg8Si12O30•8H2O. It is formed by blocks and cavities (tunnels) growing in the direction of the fibres. The tunnels, 3.7 x 10.6 Å in cross-section, are responsible for the high specific surface area and sorptive properties of sepiolite. The co-intercalation of 3-methyl cyclohex-2-en-1-one (MCH), the Douglas-Fir beetle anti-aggregation pheromone, with methanol, ethanol, acetone, or benzene into sepiolite tunnels was studied. The resulting nanohybrid materials were characterized by means of various techniques, such as multinuclear solid-state NMR spectroscopy, porosity studies and Thermal Gravimetric Analysis (TGA). This was done in the hope of obtaining slow and controlled release of MCH from the sepiolite tunnels. It was demonstrated by 13C MAS NMR (carbon-13 magic angle spinning nuclear magnetic resonance) that at room temperature there are two different MCH molecules: one MCH inside the tunnels and the other one outside the tunnels of the sepiolite. Heating nanohybrid materials at 60˚C for 20 hours removes the external MCH molecules from the sepiolite. 13C MAS NMR showed that by further heating nanohybrid materials at 120˚C for 20 hours, methanol, ethanol, or acetone peaks were greatly reduced; however, the benzene peak was not reduced. To better understand how benzene acts inside sepiolite, intercalation of d6-benzene, and co-intercalations of d6-benzene with MCH and d6-benzene with pyridine into sepiolite tunnels were carried out, and these samples were studied by the same techniques. Another technique was used in order to see whether the slow and controlled release of MCH from the sepiolite tunnels could be obtained: sepiolite-MCH nanohybrids were treated with 20 ml of 0.5 M HCl solution. It was found that when 1 gram of MCH-sepiolite sample was acid treated at room temperature, about 35% of intercalated MCH was removed from the sepiolite. The role of sepiolite clay was also studied in Maya-Blue representative structure sepiolite-indigo adduct. It is known that upon heating the sepiolite and indigo mixture, the stability that is present in Maya-Blue is achieved. It is still a mystery, however, how exactly indigo and sepiolite interact with each other.

The aims of this study were firstly to observe the breeding behaviour and embryo ology. and then to identify factors affecting the reproductive biology of the Australian native pseudomtlgilid Pseudomugil signifer (pacific blue-eye) and the impact upon it of the presence of the exotic species Gambusia holbrooki (eastern gambusia). Six species of the genus Pseudomugil, and the related Scaturiginichthys venneilipinnis, are found on the Australian continent. The normal breeding behaviour, egg surface morphology and embryology of four species of Pseudomugil (P. signijer, P. genrudae, P. tenellus and P. mellis) were first investigated, using aquarium and microscopic (light and S.E.M.) studies. The four species were divided into two groups: P. signifer and P. mellis; and P. tenellus and P. gertrudae. The study provided further evidence for the view that the embryology of the genus Pseudomugil differs markedly from that of members of the family Melanotaeniidae, with which the pseudomugilids have previously been grouped. The seasonal pattern of gonadal function in P. signifer, both in the field and in aquariums, was then investigated for populations of P. signifer from the Sydney region. It was found that P. signifer bred over the spring and summer months, commencing breeding as the temperature and daylength increased, and declining in breeding activity as daylength and temperature declined. There was no substantial difference in the pattern of reproductive activity between wild and captive stocks of P. signifer in the populations used. The impact of the presence of the introduced G. holbrooki on P. signifer was then examined, first in open-air tank experiments , and then in the field. In the tank experiments the exotic species profoundly affected the breeding of the native species. When G. holbrooki were in the tanks P. signifer did not gain weight or grow in total length (except for females given supplementary feed); ovarian weight and fecundity was greatly reduced and the ovaries were morphologically undeveloped. No eggs from P. signifer were observed in tanks which also housed G. holbrooki. G. holbrooki were observed to actively hunt and eat young P. signifer and to nip the caudal fins of adult P. signifer. The results indicate clearly, that at least in a captive situation, the presence of the exotic species has a very deleterious effect on breeding and hence possible survival, of a native population. A pilot study conducted at the same time as the harvest of the second tank study did not reveal such drastic consequences. However, even in the less confined field situation, some evidence of an interrelation between water quality, numbers of P. signifer and numbers of G. holbrooki were seen in one disturbed site (Home bush Bay). These findings suggest that a newly designed field experiment based on data collected from the power analysis of the pilot study could clarify whether G. holbrooki adversely affects P. signifer in the wild. The information gained from these studies can be used in the management of P. signifer in the wild, and serve as a model of the possible effects upon other native species.

The aims of this study were firstly to observe the breeding behaviour and embryo ology. and then to identify factors affecting the reproductive biology of the Australian native pseudomtlgilid Pseudomugil signifer (pacific blue-eye) and the impact upon it of the presence of the exotic species Gambusia holbrooki (eastern gambusia). Six species of the genus Pseudomugil, and the related Scaturiginichthys venneilipinnis, are found on the Australian continent. The normal breeding behaviour, egg surface morphology and embryology of four species of Pseudomugil (P. signijer, P. genrudae, P. tenellus and P. mellis) were first investigated, using aquarium and microscopic (light and S.E.M.) studies. The four species were divided into two groups: P. signifer and P. mellis; and P. tenellus and P. gertrudae. The study provided further evidence for the view that the embryology of the genus Pseudomugil differs markedly from that of members of the family Melanotaeniidae, with which the pseudomugilids have previously been grouped. The seasonal pattern of gonadal function in P. signifer, both in the field and in aquariums, was then investigated for populations of P. signifer from the Sydney region. It was found that P. signifer bred over the spring and summer months, commencing breeding as the temperature and daylength increased, and declining in breeding activity as daylength and temperature declined. There was no substantial difference in the pattern of reproductive activity between wild and captive stocks of P. signifer in the populations used. The impact of the presence of the introduced G. holbrooki on P. signifer was then examined, first in open-air tank experiments , and then in the field. In the tank experiments the exotic species profoundly affected the breeding of the native species. When G. holbrooki were in the tanks P. signifer did not gain weight or grow in total length (except for females given supplementary feed); ovarian weight and fecundity was greatly reduced and the ovaries were morphologically undeveloped. No eggs from P. signifer were observed in tanks which also housed G. holbrooki. G. holbrooki were observed to actively hunt and eat young P. signifer and to nip the caudal fins of adult P. signifer. The results indicate clearly, that at least in a captive situation, the presence of the exotic species has a very deleterious effect on breeding and hence possible survival, of a native population. A pilot study conducted at the same time as the harvest of the second tank study did not reveal such drastic consequences. However, even in the less confined field situation, some evidence of an interrelation between water quality, numbers of P. signifer and numbers of G. holbrooki were seen in one disturbed site (Home bush Bay). These findings suggest that a newly designed field experiment based on data collected from the power analysis of the pilot study could clarify whether G. holbrooki adversely affects P. signifer in the wild. The information gained from these studies can be used in the management of P. signifer in the wild, and serve as a model of the possible effects upon other native species.

The aims of this study were firstly to observe the breeding behaviour and embryo ology. and then to identify factors affecting the reproductive biology of the Australian native pseudomtlgilid Pseudomugil signifer (pacific blue-eye) and the impact upon it of the presence of the exotic species Gambusia holbrooki (eastern gambusia). Six species of the genus Pseudomugil, and the related Scaturiginichthys venneilipinnis, are found on the Australian continent. The normal breeding behaviour, egg surface morphology and embryology of four species of Pseudomugil (P. signijer, P. genrudae, P. tenellus and P. mellis) were first investigated, using aquarium and microscopic (light and S.E.M.) studies. The four species were divided into two groups: P. signifer and P. mellis; and P. tenellus and P. gertrudae. The study provided further evidence for the view that the embryology of the genus Pseudomugil differs markedly from that of members of the family Melanotaeniidae, with which the pseudomugilids have previously been grouped. The seasonal pattern of gonadal function in P. signifer, both in the field and in aquariums, was then investigated for populations of P. signifer from the Sydney region. It was found that P. signifer bred over the spring and summer months, commencing breeding as the temperature and daylength increased, and declining in breeding activity as daylength and temperature declined. There was no substantial difference in the pattern of reproductive activity between wild and captive stocks of P. signifer in the populations used. The impact of the presence of the introduced G. holbrooki on P. signifer was then examined, first in open-air tank experiments , and then in the field. In the tank experiments the exotic species profoundly affected the breeding of the native species. When G. holbrooki were in the tanks P. signifer did not gain weight or grow in total length (except for females given supplementary feed); ovarian weight and fecundity was greatly reduced and the ovaries were morphologically undeveloped. No eggs from P. signifer were observed in tanks which also housed G. holbrooki. G. holbrooki were observed to actively hunt and eat young P. signifer and to nip the caudal fins of adult P. signifer. The results indicate clearly, that at least in a captive situation, the presence of the exotic species has a very deleterious effect on breeding and hence possible survival, of a native population. A pilot study conducted at the same time as the harvest of the second tank study did not reveal such drastic consequences. However, even in the less confined field situation, some evidence of an interrelation between water quality, numbers of P. signifer and numbers of G. holbrooki were seen in one disturbed site (Home bush Bay). These findings suggest that a newly designed field experiment based on data collected from the power analysis of the pilot study could clarify whether G. holbrooki adversely affects P. signifer in the wild. The information gained from these studies can be used in the management of P. signifer in the wild, and serve as a model of the possible effects upon other native species.

Thesis(M.S.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.

Dissertation (Ph.D.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references.

Thesis (Ph.D.)--Murdoch University, 2004. / Thesis submitted to the Division of Science and Engineering. Bibliography: leaves 199-219.

Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 51-54).

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 129-131). Also available via the Internet.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 107-118). Also available via the Internet.