Hydrographical parameters and phytoplankton assemblages were determined along the Pondicherry, Parangipettai and Nagapattinam coastal waters, southeast coast of India. All the hydrographical parameters such as sea sur...Hydrographical parameters and phytoplankton assemblages were determined along the Pondicherry, Parangipettai and Nagapattinam coastal waters, southeast coast of India. All the hydrographical parameters such as sea surface temperature, salinity, p H, total alkalinity, dissolved oxygen and nutrients like nitrate, nitrite, inorganic phosphate and reactive silicate, chlorophyll a and phytoplankton assemblages were studied for a period of five months(May, August, September 2010, March and November 2011). Over 121 species of phytoplankton represented by 93 species of diatoms, 16 species of dinoflagellates, 9 species of blue-green algae, 2 species of greens and 1 species of silicoflagellate were recorded. High phytoplankton species diversity was found in March 2011 when salinity and nitrate concentrations were low and reactive silicate and inorganic phosphates were moderate. Species diversity was low during May 2010 when increased sea surface temperature, salinity and low nutrients availability were observed. Coscinodiscus centralis, Diatoma vulgaris and Proboscia alata were dominant, especially Coscinodiscus sp. distributed in all stations whereas Skeletonema costatum, Odontella sinensis and Ditylum brightwellii were abundant in August and September 2010. From principal component analysis and multiple regression analysis, it is evident that variables like sea surface temperature and dissolved oxygen are the most important factors influencing the seasonal pattern of phytoplankton population.展开更多
Two fl uorescent quantum clusters of gold,namely Au25 and Au8,have been synthesized from mercaptosuccinic acid-protected gold nanoparticles of 45 nm core diameter by etching with excess glutathione.While etching at pH...Two fl uorescent quantum clusters of gold,namely Au25 and Au8,have been synthesized from mercaptosuccinic acid-protected gold nanoparticles of 45 nm core diameter by etching with excess glutathione.While etching at pH~3 yielded Au_(25),that at pH 7-8 yielded Au_(8).This is the fi rst report of the synthesis of two quantum clusters starting from a single precursor.This simple method makes it possible to synthesize well-defined clusters in gram quantities.Since these clusters are highly fl uorescent and are highly biocompatible due to their low metallic content,they can be used for diagnostic applications.展开更多
基金the University Grants Commission,Govt.of India,New Delhi for financial support through UGCResearch Award(No.F.30-1/2014(SA-II)/RA-2014-16-SCTAM-4364 dated 05/02/2015)
文摘Hydrographical parameters and phytoplankton assemblages were determined along the Pondicherry, Parangipettai and Nagapattinam coastal waters, southeast coast of India. All the hydrographical parameters such as sea surface temperature, salinity, p H, total alkalinity, dissolved oxygen and nutrients like nitrate, nitrite, inorganic phosphate and reactive silicate, chlorophyll a and phytoplankton assemblages were studied for a period of five months(May, August, September 2010, March and November 2011). Over 121 species of phytoplankton represented by 93 species of diatoms, 16 species of dinoflagellates, 9 species of blue-green algae, 2 species of greens and 1 species of silicoflagellate were recorded. High phytoplankton species diversity was found in March 2011 when salinity and nitrate concentrations were low and reactive silicate and inorganic phosphates were moderate. Species diversity was low during May 2010 when increased sea surface temperature, salinity and low nutrients availability were observed. Coscinodiscus centralis, Diatoma vulgaris and Proboscia alata were dominant, especially Coscinodiscus sp. distributed in all stations whereas Skeletonema costatum, Odontella sinensis and Ditylum brightwellii were abundant in August and September 2010. From principal component analysis and multiple regression analysis, it is evident that variables like sea surface temperature and dissolved oxygen are the most important factors influencing the seasonal pattern of phytoplankton population.
基金Acknowledgments We thank Department of Science and Technology,Government of India for constantly supporting our research program on nanomaterials.
文摘Two fl uorescent quantum clusters of gold,namely Au25 and Au8,have been synthesized from mercaptosuccinic acid-protected gold nanoparticles of 45 nm core diameter by etching with excess glutathione.While etching at pH~3 yielded Au_(25),that at pH 7-8 yielded Au_(8).This is the fi rst report of the synthesis of two quantum clusters starting from a single precursor.This simple method makes it possible to synthesize well-defined clusters in gram quantities.Since these clusters are highly fl uorescent and are highly biocompatible due to their low metallic content,they can be used for diagnostic applications.
