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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Patterns of Variance and Covariance in Anthropoid Limb Proportions| Implications for Interpreting the Hominin Fossil Record

Powell, Vance C. R. 25 September 2018 (has links)
<p> Interpreting the taxonomic and behavioral implications of variation in the inferred limb proportions of fossil hominin taxa is contingent upon assessing how much variation exists in extant primate taxa and, by extension, how much of that variation is associated differences in their locomotor behaviors. However, the majority of evidence linking limb proportions to behavior in extant primates is based on taxonomically-restricted samples, or on species means as opposed to individual values, or does not account for field observations that capture the complexity of locomotor behavior in a primate taxon (see Napier &amp; Napier, 1967; Fleagle, 1988; see also Preuschoft, 2002). With regards to extinct taxa, the problem is compounded by a necessary reliance on relatively few associated skeletons, most of which are incomplete, or fragmented or both. </p><p> This thesis addresses the aforementioned issues using a) multivariate methods to quantify the relationships between limb proportions and behavioral repertoires in extant anthropoids; b) machine-learning methods to select relevant extant models with which to interpret the limb proportions of extinct taxa; and c) resampling methods to evaluate hypotheses regarding major adaptive shifts in inferred locomotor behavior.</p><p>
322

Taxonomia de Micronycteris Gray, 1866 (Chiroptera, Phyllostomidae) do Brasil

Sergio, Bruno Fernando Simões [UNESP] 09 March 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-03-09Bitstream added on 2014-06-13T20:49:37Z : No. of bitstreams: 1 sergio_bfs_me_sjrp.pdf: 1577925 bytes, checksum: 215aaeb34b0544ac5e87f75d057ef9ed (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os morcegos do gênero Micronycteris Gray, 1866 são representados por 11 espécies e são reconhecidos dois grupos artificiais: as espécies de ventre claro e as de ventre escuro. O grupo de ventre claro é composto pelas espécies: Micronycteris brosseti, Microycteris homezi, Micronycteris minuta, Micronycteris sanborni e Micronyteris schmidtorum. O grupo de ventre escuro é representado por: Micronycteris buriri, Micronycteris giovanniae, Micronycteris hirsuta, Micronycteris matses, Micronycteris megalotis e Micronycteris microtis, Destas 11, três não tem registros de ocorrência no Brasil: M. giovanniae, M. mates e M.buriri. A distribuição geográfica do gênero estende-se do sul do México até o Sul do Brasil (Estado de Santa Catarina), com registros na Bolívia, Equador, Peru, Colombia, Venezuela, Antilhas menores, Guiana, Suriname, e Guiana Francesa. Mesmo com as últimas revisões do gênero, alguns problemas de identificação das espécies ainda persistem. Os status taxonômicos de M. homezi e M. microtis são questionáveis. O objetivo do presente estudo foi contribuir para o conhecimento do gênero Micronycteris, através da caracterização da variação morfométrica dos exemplares brasileiros e também atualizar, a identificação dos espécimes depositados nas coleções brasileiras. Foram examinados 274 exemplares pertencentes às espécies do gênero Micronycteris seguindo a classificação atual. Os resultados foram concordantes com as últimas revisões para os táxons: M. hirsuta, M. minuta, M. sanborni e M. schmidtorum, e questionam a validade dos táxons M. microtis e M. homezi. Vinte e nove novos registros de ocorrência merecem atenção para as espécies: M. hirsuta, M. microtis, M. sanborni, M. minuta e M. schmidtorum e um novo registro é apontado para M. brosseti. Os resultados apontam a necessidade uma nova revisão taxonômica do gênero Micronycteris / The bats of genus Micronycteris are represented for 11 species and there are two artificial groups recognized: the dark bellied and the pale bellied species. The pale bellied group is represented for: Micronycteris brosseti, Microycteris homezi, Micronycteris minuta, Micronycteris sanborni and Micronyteris schmidtorum. The dark bellied group is represented for: Micronycteris buriri, Micronycteris giovanniae, Micronycteris hirsuta, Micronycteris matses, Micronycteris megalotis, and Micronycteris microtis. Of these, three species don´t have occurrence reported in Brazil: M. giovanniae, M. mates, e M.buriri. The geographic distribution of the genus Micronycteris ranges from south of Mexico until the south of Brazil (Santa Catarina State), with records on Bolivia, Ecuador, Peru, Colombia, Venezuela, Lesser Antilles, Guyana, Suriname, e French Guyana. Even with the latest taxonomic revisions, some problems of identification of the species still persist. The taxonomic status of M. homezi and M. microtis still remains questionable. The aim of the present study was to contribute to the knowledge about the genus Micronycteris through the characterization of the morphometric variation of the Brazilian specimens and upgrade the identification of these specimens deposited in the Brazilian collections. We examined 274 specimens belonging to the genus Micronycteris following the current classification. We agree with the latest revisions to the taxa: M. hirsuta, M. minuta, M. sanborni and M. schmidtorum, and question the validity of the taxa M. microtis and M. homezi. The results bring 29 new records of occurrence that deserve attention for the species: M. hirsuta, M. microtis, M. sanborni, M. minuta and M. schmidtorum. It is also reported a new record of M. brosseti. The results point to a need to proceed with the taxonomic revision of the Micronycteris genus
323

Avaliação hemodinâmica e morfológica da cetamina S(+) associada à cardioplegia sanguínea em coração isolado de coelho /

Ramin, Serginando Laudenir. January 2008 (has links)
Orientador: Pedro Thadeu Galvão Vianna / Banca: Eneida Maria Vieira / Banca: José Otávio da Costa Auler Junior / Banca: Moacir Fernandes de Godoy / Banca: Yara Marcondes Machado Castiglia / Resumo: Foi realizado estudo experimental em coração isolado de coelhos, perfundido pelo método de Langendorff, para avaliar o efeito da cetamina S(+) associada à cardioplegia sangüínea, durante e na manutenção por 30 minutos de parada cardíaca, conforme critérios hemodinâmicos e morfológicos. Foram utilizados 50 coelhos da linhagem Norfolk-2000, pesando 1850 a 2350 g, divididos em três grupos de corações isolados: Grupo C (n=10) cardioplegia sangüínea; Grupo CC (n=10) cetamina S(+) associada à cardioplegia sangüínea e, Grupo PA (n=5) parada cardíaca anóxica. A função ventricular foi analisada pela técnica de balão intraventricular. Fragmentos de um único ventrículo esquerdo foram analisados como padrão de normalidade histopatológica. A análise estrutural e ultra-estrutural de fragmentos do ventrículo esquerdo após a parada cardíaca imediata por cardioplegia ou anóxica, seguida por período de manutenção. Foram obtidos os seguintes resultados: 1. Avaliação hemodinâmica. Pressão desenvolvida intraventricular (PDes): grupo C (76,39±17,69 mmHg e 62,08±32,13 mmHg) p <0,05; grupo CC (89,26±16,37 mmHg e 52,62±24,91 mmHg) p<0,05; grupo PA (77,96±12,67 mmHg e 60,81±29,68 mmHg), pré e pós-tratamento, respectivamente. Primeira derivada temporal da pressão ventricular na sua deflexão positiva (dP/dt+): grupo C (1236±181,15 mmHg/seg e 1150,20±174,44 mmHg/seg); grupo CC (1372,61±214.19 mmHg/seg e 1058,52±255,10 mmHg/seg) p<0,05; grupo PA (1252,39±99,76 mmHg/seg e 1115,10±73,07 mmHg/seg), pré e pós-tratamento, respectivamente. Primeira derivada temporal em sua deflexão negativa (dP/dt-): grupo C (856,01±132,26 mmHg/seg e 783,62±177,54 mmHg/seg); grupo CC (948,11±106,34 mmHg/seg e 760,28±219,37 mmHg/seg); grupo PA (911,02±74,53 mmHg/seg e 818,95±219,09 mmHg/seg), pré e pós-tratamento, respectivamente. 2. Avaliação morfológica. / Abstract: An experimental study in isolated heart of rabbits, perfused by the Langendorff system, to evaluate the effect of S(+) ketamine associated with blood cardioplegia during and in the maintenance during 30 minutes of the cardiac arrest according to hemodynamic and morphological criteria. A total of 50 Norfolk-2000 rabbits, weighting 1850 to 2350 g, were divided into three groups of isolated hearts: blood cardioplegia-BC (n=10); S(+) ketamine associated with blood cardioplegia-K (n=10), and anoxic cardiac arrest-CA (n=5). The ventricular function was analyzed by the intra-ventricular balloon technique. The structural and ultrastructural analysis of fragments of the left ventricle after immediate cardiac arrest by cardioplegia or anoxic arrest, followed by maintenance period. The fragments of the left ventricle were analyzed as pattern of histopathological normality. The following results were obtained: 1. Hemodynamic evaluation. Intra-ventricular developed pressure (IVDP) was: group BC (76.39±17.69 mmHg and 62.08±32.13mmHg) p<0.05; group K (89.26±16.37mmHg and 52.62±24.91mmHg) p<0,05; group CA (77.96±12.67mmHg and 60.81±29.68mmHg), pre and posttreatment, respectively. First derivative of intraventricular pressure in its positive deflection (dP/dt+) was: group BC (1236±181.15 mmHg/sec and 1150.20±174.44 mmHg/seg); K (1372.61±214.19 mmHg/sec and 1058.52±255.10mmHg/seg) p<0.05; CA (1252.39±99.76 mmHg/sec and 1115.10±73.07 mmHg/sec), pre and posttreatment, respectively. First derivate pressure in its negative deflection (dP/dt-) was: group BC (856.01±132.26 mmHg/sec and 783.62±177.54 mmHg/sec); K (948.11±106.34 mmHg/sec and 760.28±219.37 mmHg/sec); CA (911.02±74.53 mmHg/sec and 818.95±219.09 mmHg/sec) pre and posttreatment, respectively. 2. Morphological evaluation. / Doutor
324

Estudos taxonômicos dos grilos troglófilos do gênero Strinatia Chopard, 1970 e uma hipótese de relacionamento filogenético para suas espécies (Orthopthera, Phalangopsidae, Luzarinae) /

Bolfarini, Marcio Perez. January 2011 (has links)
Orientador: Ricardo Cardoso Benine / Coorientador: Francisco de Assis Ganeo de Mello / Banca: Maria Elina Bichuette / Banca: Silvio S. Nihei / Banca: Edison Zefa / Banca: Carmen C. Fontanetti / Resumo: Espécies de grilos que estão diretamente ligadas ao ambiente hipógeo possuem problemas especiais para conservação própria: a fragilidade intrínseca e aspectos distintos dessas comunidades, incluindo a alta taxa de endemismo, morfologia, ecologia e os diferentes comportamentos entre troglófilos. A presença de espécies novas de cavernícolas do gênero Strinatia possibilitou o estudo taxonômico e a elaboração de uma hipótese filogenética para esse grupo tão peculiar. O resultado foi a seguinte relação: ((cancelloae (gnaspini (ibitipoca (atibaiensis + valinhensis)))) (boraceana + caissara) (ribeiraopirensis) (brevipennis (ricardoi + elinae)), (apiaiensis (tamandarensis + campolargoensis)) (cerroazulensis (guapiarana (arataca (leo (adrianopolensis + atratus)))))). O presente trabalho traz a descrição de 22 espécies novas, a redescrição e transferência de Strinatia teresopolis para um gênero novo, assim como a chave de identificação / Abstract: Cricket species that are directly related to the hypogean environment have their own special problems for conservation: the intrinsic fragility and distinct aspects of these communities, including the high rate of endemism, morphology, ecology and the different behaviors between troglophyles. The presence of a new cave species of the genus Strinatia allowed the taxonomic study and the elaboration of a phylogenetic hypothesis for this unique group. The result was the following relationship: ((cancelloae (gnaspini (ibitipoca (atibaiensis + valinhensis)))) (boraceana + caissara) (ribeiraopirensis) (brevipennis (ricardoi + elinae)), (apiaiensis (tamandarensis + campolargoensis)) (cerroazulensis (guapiarana (arataca (leo (adrianopolensis + atratus)))))). The study shows the description of 22 new species, redescription and change of Strinatia teresopolis for a new genus and the identification key the genus / Doutor
325

Análise do desenvolvimento embrionário de espécimes provenientes dos cruzamentos interespecíficos entre Pseudoplatystoma corruscans e leiarius marmoratus

Almeida, Isângela Rodrigues de Oliveira [UNESP] 04 March 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-04Bitstream added on 2014-06-13T20:00:06Z : No. of bitstreams: 1 almeida_iro_me_botib.pdf: 1159803 bytes, checksum: 8b692d8d747287b1fa84a1b81e1c3540 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este projeto de pesquisa teve como objetivo analisar o desenvolvimento de embriões provenientes dos cruzamentos interespecíficos entre as espécies de teleósteos neotropicais, pintado (Pseudoplatystoma corruscans) e jandiá (Leiarius marmoratus). As coletas foram realizadas no Centro Nacional de Pesquisa e Conservação de Peixes Continentais - CEPTA/ICMBIO, Pirassununga – SP e na Piscicultura Muriti, Nova Mutum – MT. A reprodução foi feita através de indução hormonal, utilizando extrato bruto de hipófises de carpa. Os ovos foram incubados em incubadoras verticais e coletados desde o momento da fertilização até a eclosão das larvas. Os ovos dos parentais P. corruscans e L marmoratus e seus híbridos, são esféricos, demersais, córion nítido e espaço perivitelínico pequeno após a hidratação, não sendo observada a presença de gota de óleo na vesícula vitelínica durante todo o desenvolvimento embrionário. A média do espaço perivitelínico do L. marmoratus foi de 215,9μm, do P. corruscans foi de 352,5μm, do híbrido I foi de 561μm e do híbrido II foi de 247,2μm. O diâmetro médio do ovo do L. marmoratus foi de 589,6μm, do P. corruscans foi de 867,3μm, do híbrido I foi de 765,3μm e do híbrido II foi de 581μm. O período de incubação do P. corruscans e do híbrido I foi de 13 horas, à temperatura média de 28,7°C respectivamente. Já para o L. marmoratus e do híbrido II foi de 14 horas para o parental e 12 horas para o híbrido, a uma temperatura média de 28,3°C. Sendo estabelecidos os seguintes estágios embrionários: zigoto, clivagem, gástrula, organogênese e eclosão e estes divididos em fases. O estágio de clivagem foi dividido nas fases de 2, 4, 8, 16, 32, 64 células e na fase de mórula. O estágio de gástrula apresentou as fases de 25%, 50%, 75%, 90% e 100% do movimento morfogenético de epibolia e o estágio de organogênese... / The main of this research project was analyze the embryos development from the inter-specific crossing between the neotropical teleostei species, pintado (Pseudoplatystoma corruscans) e jandiá (Leiarius marmoratus). The samples were realized in the National Research and Conservation Nucleus of Continental Fishes – CEPTA/ICMBIO, Pirassununga – SP in the Buriti Fish Farming, Nova Mutum – MT. The reproduction was made through the hormonal induction, using gross extract of pituitary from carpa. The eggs were incubated in vertical incubators and collected since the fertilization time until the larval hatching. The eggs of the parents P. corruscans e L. marmoratus and their hybrids, are spherical, demersal, distinct chorion and small perivitelline space after the hydration without observation of the presence of drop oil in the vitelline vesicle during all embryonic development. The mean of the perivitelline space of the L. marmoratus was 215,9μm, in the P. corruscans was 352,5μm, in the hybrid I was 589,6μm and 247,2μm in the hybrid II. The mean diameter of the egg in L. marmoratus was 589,6μm, in P. corruscans was 867,3μm, in the híbrido I was 765,3μm and 581μm in the hybrid II. The incubation period of P. corruscans and the híbrido I was 13 hours , in the mean temperature of 28,7°C. However in L. marmoratus and Hybrid II was 14 hours for the parental and 12 hours for the hybrid in the mean temperature of 28,3°C. It was established the following embryonic stages: zygote, cleavage, gastrula, organogenesis and hatching and this divided in phases. The cleavage stage was divided in the phases 2, 4, 8, 16, 32, 64 cells and in the morula phase. The gastrula stage showed the phases 25%, 50%, 75%, 90% and 100% of morphogenetic movements of epiboly and the organogenesis stage was divided in the neurula, segmentation and larval phases... (Complete abstract click electronic access below)
326

Morphology evolution in dealloying

January 2013 (has links)
abstract: Dealloying, the selective dissolution of an elemental component from an alloy, is an important corrosion mechanism and a technological significant means to fabricate nanoporous structures for a variety of applications. In noble metal alloys, dealloying proceeds above a composition dependent critical potential, and bi-continuous structure evolves "simultaneously" as a result of the interplay between percolation dissolution and surface diffusion. In contrast, dealloying in alloys that show considerable solid-state mass transport at ambient temperature is largely unexplored despite its relevance to nanoparticle catalysts and Li-ion anodes. In my dissertation, I discuss the behaviors of two alloy systems in order to elucidate the role of bulk lattice diffusion in dealloying. First, Mg-Cd alloys are chosen to show that when the dealloying is controlled by bulk diffusion, a new type of porosity - negative void dendrites will form, and the process mirrors electrodeposition. Then, Li-Sn alloys are studied with respect to the composition, particle size and dealloying rate effects on the morphology evolution. Under the right condition, dealloying of Li-Sn supported by percolation dissolution results in the same bi-continuous structure as nanoporous noble metals; whereas lattice diffusion through the otherwise "passivated" surface allows for dealloying with no porosity evolution. The interactions between bulk diffusion, surface diffusion and dissolution are revealed by chronopotentiometry and linear sweep voltammetry technics. The better understanding of dealloying from these experiments enables me to construct a brief review summarizing the electrochemistry and morphology aspects of dealloying as well as offering interpretations to new observations such as critical size effect and encased voids in nanoporous gold. At the end of the dissertation, I will describe a preliminary attempt to generalize the morphology evolution "rules of dealloying" to all solid-to-solid interfacial controlled phase transition process, demonstrating that bi-continuous morphologies can evolve regardless of the nature of parent phase. / Dissertation/Thesis / Ph.D. Materials Science and Engineering 2013
327

Aspects of the morphology and taxonomy of the Nematode genera Xiphinema and Xiphidorus

Hutsebaut, Mieke 10 March 2014 (has links)
Ph.D. (Nematology) / This thesis consists of three parts: the first and major part dealing with Xiphinema species from southern Africa. the second shorter part with Xiphinema species from the Aldabra Atoll. and the last part with aspects of the ultrastructure of Xiphidorus balcarceanus Chaves & Coornans, 1984 from Argentina. Nine new Xiphinema species are described from southern Africa. The three new species X. erriae, X. ripogranum and X. lacrimaspinae are all related to X. meridianum Heyns. 1971. but can be differentiated by the nature of the uterine spines and inclusions in the pseudo-Z-organ. tail shape. ovejector shape and the presence or absence of males. Two new longtailed species related to X. fJagellicaudatum Luc, 1961. viz. X. judex and X. dracomontanum, can be distinguished by body length. tail length and shape. the nature of the pseudo-Z-organ and presence or absence of males. Three new species with digitate or subdigitate tails are described, viz. X. capriviense from South West Africa-Namibia, which is characterised i.a. by peculiar inclusions in the uterus. X. pongolense from northern Natal which is quite similar to X. umobae Heyns & Spaull, 1979. and X. simplex from the Transkei, in which the uterus is devoid of any inclusions. The last new species to be described is X. ometizulu, which belongs to the X. zulu Heyns, 1965 and X. mampara Heyns, 1979 species complex. The abovementioned species complex was studied in detail, and X. mampara was found to consist of three different forms, one amphimictic, which is herein called X. mampara f. bisexuale. and two parthenogenetic forms. called X. mampara f. major and X. mampara f. minor. Redescriptions based on new populations are given for X. clavatum Heyns, 1965 and X. imitator Heyns, 1965. and additional information is also offered for X. umobae. A dichotomous key is presented for the identification of the 54 species of Xiphinema recorded from southern Africa. and the known distribution of these species is shown in a series of maps. X. brevicolle Lordello & Da Costa. 1961. X. italiae Meyl. 1953 and X. malagasi tuc, 1973 are reported from the Aldabra Atoll. All three species are described and figured, and compared with previous descriptions. The ultrastructure of the cuticle and feeding apparatus of Xiphidorus ba/carceanus was studied and compared with some other Longidoridae species.
328

Morphology and taxonomy of some nematodes of the orders Teratocephalida, Enoplida, Dorylaimida, Chromadorida and Isolaimida

Swart, Antoinette 12 August 2014 (has links)
D.Phil. (Nematology) / The science of taxonomy or the organisation and labelling of organisms may strike many as dull and stuffy but everyone working in this fascinating field finds that it leads to some of the most searching and interesting questions. Taxonomists are confronted by a well organised world of nature, exactly that what prompted the great taxonomist Linnaeus to develop his clear, hierarchical method of classification. But at the same time they are faced with a bewildering diversity and variation within this organised whole. Seeking to order the stable units in the midst of this diversity is the descriptive task of taxonomy. But many taxonomists go further than that, they seek a theory and ask: what causes life to be ordered? Here they land in the middle of philosophical debate and controversy. The field of taxonomy has, unfortunately, been divided by arguments about what a species is, how to demarcate a species, and even whether they are real or not. Today this "species question" is phrased in broader terms. The real question is not whether species are fixed but whether there is any stable, objective unit in nature. What do the patterns of similarity and difference mean - creation according to a common plan with the potential of variation, or descent from a common ancestor with modifications? Charles Darwin believed that change is unlimited, that species are infinitely variable. He thought that species could vary indefinitely and in any direction. Creationists on the other hand, believe that change is limited by a basic organic "unit", the "created kind" and within the boundary of that fundamental unit, variation can be profuse, but it can never lead to the creation of a new basic type. This is near the essentialism as taught by Aristotle nearly 2000 years ago. Aristotle thought that each species embodies an eternal, unchanging ideal or archetype. The problem with this view is that it assumed a single form or pattern. Most biologists until the time of Darwin held to the typological view, a view considered by many scientists today as very plausible. This theory holds that the organic world is discontinuous, that all major groups of organisms are separate and breed true to type. A species is also defined by a cluster of characteristics - each member of the species may have some but not all of the diagnostic features. Another view is cladism, founded by the entomologist, Willy Hennig. It is concerned with the patterns found in nature and involves the finding of the positive and verifiable characters of the various species and determining how all species fit into the animal kingdom.
329

Morfologie, kardiologie en taksonomie van sommige Suid-Afrikaanse Xiphinema spesies

Kruger, Johannes Christiaan de Wet 18 March 2014 (has links)
Ph.D. (Zoology) / Please refer to full text to view abstract
330

The preparation and characterization of hollow fibre membranes for gas separation

Senn, Simon Charles January 1988 (has links)
A dry-jet wet-spinning process developed industrially for the preparation of hollow fibre membranes suitable for gas separation applications, has been reproduced on a laboratory scale. Polysulphone hollow fibres were spun from a variety of solvents and their gas transport properties were characterized using equipment built during the course of the research. The phase inversion process of membrane formation was studied in order that the best morphological structure could be produced. The spinning parameters were studied to establish their influence on the fibre dimensions. Further relationships were then sought between the gas transport properties and the fibre dimensions and spinning parameters. The behaviour of the membranes to both single gases and gas mixtures was studied. Both the permeation rate constants and the separation factors determined from the mixture permeation were found to be lower than the values predicted from the single gas permeation experiments. A model was developed to help understand the competitive nature of the adsorption-diffusion process and explain the differences in values recorded from the single gas and mixture studies. Experiments aimed at improving membrane performance were based on modification of the already established polysulphone hollow fibre. Modification of the selective surface layer of the hollow fibre membranes was considered to be the best approach. Coating of the fibres, other than to repair damage to the skin layer, was found to result in too large a decrease in permeability. Sulphonation of the surface layer was achieved using sulphur trioxide, although little improvement in the membrane performance was recorded. The sulphonation experiment results were, however, sufficiently encouraging to recommend future work.

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