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Monitoring of Phenol in Wastewater Bioremediation by HPLC 总被引:1,自引:0,他引:1
KC Ng G Poi CM Puah V De Castro PL Rogers 《Environmental monitoring and assessment》1997,44(1-3):433-436
Bioremediation emphasizes the detoxification and destruction of toxic substances by microorganisms. Wastewater obtained from an industrial concern was solvent extracted with methyl alcohol and dichloromethane and analysed by GC/MS. Besides phenol, a large variety of organic compounds were detected. Under controlled laboratory conditions, the wastewater was innoculated with a mixed culture of microorganisms specially selected for their abilities to degrade phenol. Samples were collected at regular intervals from the stirred tank bioreactor and analysed for phenol by reverse phase HPLC with a C18 column. Results shows that from an initial phenol concentration of 987 ppm, slightly more than 50% was destroyed within 163 hours. The dry weight of the microorganisms and the plate count (CFU/ml) shows a steady increase from 0.5238 gms to 0.5355 gms and from 1.1E+9 to 1.94E+13 respectively over the same period. This suggested that the phenol was consumed by the microorganisms as the sole carbon source. 相似文献
2.
Balachandran KK Jayalakshmy KV Laluraj CM Nair M Joseph T Sheeba P 《Environmental monitoring and assessment》2008,139(1-3):217-226
The interaction effects of abiotic processes in the production of phytoplankton in a coastal marine region off Cochin are
evaluated using multiple regression models. The study shows that chlorophyll production is not limited by nutrients, but their
physiological regulations (responses to nutrients, pH, temperature and salinity) are mainly responsible for the increased
biological production. The model explaining 77% of variability for chlorophyll a production is indicative of preconditioning of the coastal waters. The phytoplankton production is found to be sensitive
to the environment, which varies seasonally. Further, the study suggests that supply of organic matter and grazing of zooplankton
(not included) would improve the model efficiency. Despite this, the good agreement in the computed and measured chlorophyll
a values shows that step-up multiple regression model is a useful tool to understand the influence of environmental variables
on the production of phytoplankton in these coastal waters. 相似文献
3.
Laluraj CM Krishnan KP Thamban M Mohan R Naik SS D'Souza W Ravindra R Chaturvedi A 《Environmental monitoring and assessment》2009,149(1-4):377-383
The scanning electron microscopy-energy dispersive spectroscopic (SEM-EDS) study of selected samples from an ice core collected from Central Dronning Maud Land (CDML), East Antarctica, revealed several microparticles. They are mainly siliceous and carbonaceous particles and have distinct variations in their shape and composition. The morphology and major element chemistry of the particles suggest their origin from either volcanic eruptions or continental dust. The EDS analysis revealed that the volcanic particles are enriched in silica (average SiO2 62%), compared to the continental dust particle (average SiO2 56%). We found that the tephra relating to Agung (1963) and Karkatau (1883) volcanic eruptions, as recorded, in the ice core harbored microbial cells (both coocoid and rods). The occurrence of organic and inorganic particles which bear relation to volcanic eruption and continental dust implies significant environmental changes in the recent past. 相似文献
4.
Joseph T Shaiju P Laluraj CM Balachandran KK Nair M George R Nair KK Sahayak S Prabhakaran MP 《Environmental monitoring and assessment》2008,143(1-3):355-361
The bloom-infested waters along the southwest coast of India were assessed to bring about the probable cause related to the excessive algal production. Low nitrate and silicate concentrations were concomitant with slightly higher levels of phosphate. The silicate depletion in the bloom area is possibly an indication of community succession (diatom to dinoflagellate), since it was completely utilized by the preceding diatom blooms. The dinoflagellates in this region could have been advected from the northern regions where it was noticed during the previous months. 相似文献
5.
Spatial distribution of pH, electrical conductivity (EC), total dissolved solids (TDS), fluoride and total iron content of
ground water samples collected from the muvattupuzha river basin, Kerala, India, has been studied for pre monsoon and post
monsoon periods of year 2001. Results showed the groundwater of the basin is acidic for which the pH values ranged between
5.5 and 8.0. Average EC was found to be less than 100 μS/cm, for most of the study region. The pre monsoon minimum and maximum
TDS were found as 25.6 and 227.84 mg/L respectively, where as post monsoon values ranged between 16 and 162.56 mg/L. The relatively
low EC and TDS values found both during the seasons in the lateritic terrain of the river basin signifies the lower residence
time of ground water with the country rock. This makes the groundwater quality of this river basin as good. Pre monsoon season
samples showed high total iron content than that during the post monsoon period. During the study period values of the fluoride
contents were found to be within the permissible limits. 相似文献
6.
Laluraj CM Kesavadas V Balachandran KK Gerson VJ Martin GD Shaiju P Revichandran C Joseph T Nair M 《Environmental monitoring and assessment》2007,125(1-3):41-45
Water quality in the Cochin Estuary, southwest coast of India during the tsunami attack was assessed and compared with the
pre and post tsunami characteristics. From the results obtained, it is evident that a drastic change in hydrography has been
inflicted by the energy transferred through the tsunami, which disturbed the entire estuarine embayment. However, the post
tsunami water quality showed normal levels indicating that the region has recovered from the tsunami impacts. 相似文献
7.
Jane T. Bhaskar S. C. Tripathy P. Sabu C. M. Laluraj S. Rajan 《Environmental monitoring and assessment》2016,188(4):224
Phytoplankton species distribution and composition were determined by using microscopy and pigment ratios in the Kongsfjorden during early autumn 2012. Variation in sea surface temperature (SST) was minimal and matched well with satellite-derived SST. Nutrients were generally limited. Surface phytoplankton abundance ranged from 0.21?×?103 to 10.28?×?103 cells L?1. Phytoplankton abundance decreased with depth and did not show any significant correlation with chlorophyll a (chl a). Column-integrated phytoplankton cell counts (PCC) ranged from 94.3?×?106 cells m?2 (Kf4) to 13.7?×?106 cells m?2 (Kf5), while chl a was lowest at inner part of the fjord (6.3 mg m?2) and highest towards the mouth (24.83 mg m?2). Biomass from prymnesiophytes and raphidophytes dominated at surface and 10 m, respectively. The contribution of Bacillariophyceae to biomass was low. Generally, heterotrophic dinoflagellates were great in abundance (12.82 %) and ubiquitous in nature and were major contributors to biomass. Various chl pigments (chl b, chl c, phaeopigments (phaeo)) were measured to obtain pigment/chl a ratios to ascertain phytoplankton composition. Phaeo were observed only in inner fjord. Chl b:a ratios and microscopic observations indicated dominance of Chlorophyceae at greater depths than surface. Furthermore, microscopic observations confirmed dominance of chl c containing algae throughout the fjord. The study indicates that pigment ratios can be used as a tool for preliminary identification of major phytoplankton groups. However, under the presence of a large number of heterotrophic dinoflagellates such as Gymnodinium sp. and Gyrodinium sp., pigment signatures need to be supplemented by microscopic observations. 相似文献
8.
Geochemical index of trace metals in the surficial sediments from the western continental shelf of India, Arabian Sea 总被引:1,自引:0,他引:1
The present study focuses on the determination and abundance of trace metals (viz. Cu, Ni, Zn, Cr, Co, Cd, Mn and Fe) in the
surficial sediments of west coast of Arabian Sea along the Indian subcontinent. Sediment samples were collected from three
transects along the western continental shelf of Arabian Sea. The enrichment of Fe and Mn in coastal oxic-sediments indicates
the precipitation of these redox sensitive elements as Fe- and Mn-hydroxides and oxides, whereas the low Fe and Mn concentrations
in the oxygen deficient sediments of deeper stations reflects the dissolution of their hydroxides and oxides. Concentrations
of fairly redox insensitive trace metals like Cu, Ni, Zn, Cr and Cd (with the exceptions of Cr) showed higher values at nearshore
sediments, then it decreased towards seaward and again showed a slight increase at oxygen minimum stations in all the three
transects. This geochemical variability in their distributional characteristics is mainly associated with the extent to which
the precipitation or dissolution of Fe- and Mn-oxides/hydroxides occur since the scavenging or releasing effects of Fe- and
Mn-oxides/hydroxides act as significant ‘sinks’ or ‘sources’ of heavy metals. The change in wind pattern, coastal upwelling
and increased productivity are also the reported factors which influence the biogeochemical cycling of trace metals in the
surface sediments of west coast of India. Enrichment factor generally showed a high gradient accumulation from nearshore to
shelf. 相似文献
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