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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.
41

Regional approaches to controlling land-based marine pollution the possible role of ASEAN in Southeast Asia /

Triatmodjo, Marsudi, January 1990 (has links)
Thesis (LL. M.)--Dalhousie University, 1990. / Includes bibliographical references (leaves 249-272).
42

Marine education and research centre

Wu, Yan-cheuk. January 1994 (has links)
Thesis (M.Arch.)--University of Hong Kong, 1994. / Includes special study report entitled : Aquarium, laboratory and floating structure. Includes bibliographical references. Also available in print.
43

The chemistry of Briareum asbestinum

Unknown Date (has links)
Briareum asbestinum, a soft coral, is a rich source of diterpenoid natural products. The secondary metabolites of B. asbestinum fall into four classes : asbestinins, briarellins, briareolate esters, and briaranes. Briareolate esters have been shown to possess biological activity and were previously only reported from Tobago. Our group recently isolated briareolate esters from a specimen collected off the coast of Boca Raton, Florida. To determine whether location has an impact on the chemistry produced by the organism, a method to discern between chemotypes was sought. Several techniques including thin layer chromatography (TLC), high performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR), and sclerite analysis were employed, with NMR being the most successful method. By utilizing both 1H and COSY NMR experiments, it is possible to differentiate between the chemotypes of B. asbestinum. Application of this method allowed analysis of chemical variability with respect to location. / by Melody D. Rondeau. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / System requirements: Adobe Reader. / Mode of access: World Wide Web.
44

Isolation of briareolate esters from Briareum asbestinum

Unknown Date (has links)
by Rian J. Meginley. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader. / The gorgonian Briareum asbestinum is widely studied because it possesses highly oxygenated novel structures, many of which exhibit useful biological activities. Recently, two new briarane diterpenoids, briareolate esters J and K, together with two known briareolate esters have been isolated from a specimen of Briareum asbestinum collected off the coast of Boca Raton, Florida. The method used was a 96-well plate real-time cell electronic sensing (RT-CES) system to discover compounds that impact human embryonic stem cell growth. The compounds were isolated using reversed phase polystyrene divinylbenzene chromatographic support HP20ss followed by normal phased HPLC using a luna silica column. The structures of the compounds were established though the interpretation of spectroscopic data. Activity testing was conducted against hESCs (BG02) with briareolate ester J showing no inhibition activity and briareolate ester K showing mild activity with an EC50 value of 25 (So(BM. These results confirm that the exact confirmation and existence of the (E,Z)-dienone is related to the activity that was observed with the previously isolated briareolate esters L and M.
45

Development of analytical methods for the speciation of arsenic in the marine environment

Momplaisir, Georges-Marie January 1995 (has links)
Several biologically important arsenic compounds including methylarsonate, trimethylarsine oxide, tetramethylarsonium ion, arsenobetaine and arsenocholine were prepared, in good yields, from sodium arsenite, or dimethylarsinic acid. These organoarsenic compounds together with arsenite, arsenate and dimethylarsinic acid were used as standards for the development of analytical methods for determining the levels of individual arsenic compounds (arsenic speciation) present in natural matrices. / Arsenobetaine, arsenocholine and tetramethylarsonium ion were separated by high performance liquid chromatography (HPLC) with on-line detection by thermochemical hydride generation (THG)-AAS. The analytes were eluted from the cyanopropyl bonded phase HPLC column with a 1% acetic acid methanolic mobile phase which also contained diethyl ether triethylamine, and trimethylsulfonium iodide or picrylsulfonic acid. A surface response methodology and a univariate optimization procedure were used to determine the optimum concentration of solvent modifiers in the methanolic mobile phase. Limits of detection in the range 4-5 ng (as As) were obtained for the arsonium analytes under optimum chromatographic conditions. / A simple phenol extraction procedure was developed to isolate arsonium analytes from edible marine tissues (lobster tail muscle, peeled and deveined shrimp, and cod fillet), cod liver oil and human urine. The crude extracts were separated on the cyanopropyl column using a methanolic mobile phase and detected on-line by THG-AAS. Recoveries from tissues or from urine which had been spiked at 0.1-3.4 $ mu$g of As cation/g of fresh weight were 80% or greater for each of five sample types. / An improved HPLC-AAS interface which was compatible with either aqueous or organic mobile phases was also developed. The interface provided approximately equivalent responses to different arsenic oxidation states which resulted in low to subnanogram chromatographic limits of detection for arsenic oxyanions and arsonium cations in an aqueous or methanolic mobile phase. Nascent As anions and As cations were conveniently coextracted from aqueous solution or from fish muscle by phenol extraction and quantified in the same chromatographic run. This method has been applied to a standard reference sample of dogfish muscle (DORM-1), a marine reference sediment sample (PACS-1) and to sediment porewaters (SAG-15) from the Saguenay Fjord.
46

Origin, formation and environmental significance of sapropels in shallow Holocene coastal lakes of Southeastern Australia.

Mee, Aija C. January 2007 (has links)
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / The aims of this investigation on the Holocene carbonate successions of three shallow, ephemeral lakes from the Cooring coastal plain were: to determine the timing of the sapropel ’events’ in the three lakes; to determine the origin of the sapropelic organic matter and evaluate changes; to establish whether sapropel deposition in these shallow, coastal lakes primarily reflects increased organic matter delivery to the sediments during periods of enhanced terrestrial input and/or aquatic productivity, and; to relate sapropel deposition in these three lakes to both regional and global palaeoenvironment reconstructions. --p. 23-24. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1324064 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007
47

Origin, formation and environmental significance of sapropels in shallow Holocene coastal lakes of Southeastern Australia.

Mee, Aija C. January 2007 (has links)
Title page, contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / The aims of this investigation on the Holocene carbonate successions of three shallow, ephemeral lakes from the Cooring coastal plain were: to determine the timing of the sapropel ’events’ in the three lakes; to determine the origin of the sapropelic organic matter and evaluate changes; to establish whether sapropel deposition in these shallow, coastal lakes primarily reflects increased organic matter delivery to the sediments during periods of enhanced terrestrial input and/or aquatic productivity, and; to relate sapropel deposition in these three lakes to both regional and global palaeoenvironment reconstructions. --p. 23-24. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1324064 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007
48

An education plan for secondary school projects in marine ecology at Hoi Ha Wan Marine Park /

Lau, Wai-lan, Rossetti. January 1900 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 53-54).
49

Biological monitoring and its value in assessing the marine environment of Hong Kong /

Tsui, Man-leung. January 1996 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 42-47).
50

The potential for using biomonitoring in the Hong Kong marine environment /

Yu, Pui-shan. January 1996 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf [64-67]).

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