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581.
Piper (1944) diagram has been the basis for several important interpretations of the hydrogeochemical data. As seen in this diagram, most natural waters contain relatively few dissolved constituents, with cations (metals or bases) and anions (acid radicles) in chemical equilibrium with one another. Apart from the facies representation, the composition of the mixed sample can be identified in terms of the composition of the parental solution. To bring out this advantage of the Piper diagram, a study was conducted in the Kalpakkam region of Tamilnadu, South India. By taking the geology and water table into consideration, two sample locations were selected as parent solution and third one as the mixture sample. All three samples were analyzed for calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), chloride (Cl), sulphate (SO4) and phosphate (PO4) by Ion Chromatograph (Metrohm IC 861). HCO3 was determined by volumetric titration. The Piper diagram shows that parent solutions clustered towards Na-Mg-Ca-HCO3-Cl and Na-HCO3 facies, and the mixing sample belongs to Na-Mg-HCO3 facies. Phreeqc interac-tive (Ver 2.8) along with the original composition of the mixture sample was used to correlate the mixing proportion identified by the Piper diagram.  相似文献   
582.
The Markandeya River Basin stretches geographically from 15o56′ to 16o08′ N latitude and 74o37′ to 74o58′ E longitude, positioned in the midst of Belgaum district, in the northern part of Karnataka. The groundwater quality of 54 pre-monsoon samples in the Markandeya River Basin was evaluated for its suitability for drinking and irrigation purposes by estimating pH, EC, TDS, hardness and alkalinity besides major cations (Na+, K+, Ca2+, Mg2+) and anions (HCO3–, Cl–, SO42–, PO43-, F-, NO3–), boron, SAR, % Na, RSC, RSBC, chlorinity index, SSP, non-carbonate hardness, Potential Salinity, Permeability Index, Kelley’s ratio, Magnesium hazard and Index of Base Exchange. Negative Index of Base Exchange indicates the chloro-alkaline disequilibrium in the study area and the majority of water samples fall in the rock dominance field based on Gibbs’ ratio. Permeability indices of classes I and II suggest suitability of groundwater for irrigation. Based on Cl, SO4, HCO3 concentrations, water samples can be classified as normal chloride (96.3%) and normal sulfate (94.4%) and normal bicarbonate (44.4%) water types.  相似文献   
583.
To help in ascertaining methane content of lignite reservoir in China,the isothermal ad-sorption measurements of methane have been performed on moisture-equilibrated coals of some typical lignite-bearing basins,which comprise maximum reflectance of vitrinite(Ro,max) ranging from 0.24% to 0.50%.Related to other coal properties,our analysis shows that methane adsorption of lignite is mainly affected by coalification,as well as by maceral composition,moisture content,and seam temperature.Maximum methane capaci...  相似文献   
584.
There is a need for sensitive biological effect methods by which to detect impacts of chronic exposure to low concentrations of contaminants. Two methods shown to be potentially useful for monitoring purposes in fish include lysosomal membrane stability and peroxisome proliferation. These biological endpoints were assessed in Atlantic cod (Gadus morhua) head kidney following exposure to a mixture of produced water components including polycyclic aromatic hydrocarbons, phenol, and alkylphenols. Lysosomal damage of head kidney cells occurred within the first two weeks and did not recover during the entire exposure period (32 weeks). Lysosomal membrane stability was not affected by gender and was responsive at low concentrations of contamination, indicating that lysosomal membrane stability measured in the head kidney could be a useful biomarker for effects of offshore pollution. Peroxisome proliferation, measured as acyl-CoA oxidase activity in the head kidney, appeared to be a potential biomarker in male cod exposed less than 16 weeks.  相似文献   
585.
Surface measurements of aerosol physical properties were made at Anantapur(14.62°N,77.65 °E,331 m a.s.l),a semiarid rural site in India,during August 2008-July 2009.Measurements included the segregated sizes of aerosolsas as well as total mass concentration and size distributions of aerosols measured at low relative humidity(RH<75%) using a Quartz Crystal Microbalance(QCM) in the 25-0.05 μm aerodynamic diameter range.The hourly average total surface aerosol mass concentration in a day varied from 15 to 70 μg m-3,with a mean value of 34.02±9.05μgm-3 for the entire study period.A clear diurnal pattern appeared in coarse,accumulation and nucleation-mode particle concentrations,with two local maxima occurring in early morning and late evening hours.The concentration of coarse-mode particles was high during the summer season,with a maximum concentration of 11.81±0.98μgm-3 in the month of April,whereas accumulationmode concentration was observed to be high in the winter period contributed >68% to the total aerosol mass concentration.Accumulation aerosol mass fraction,A f(=Ma/Mt) was highest during winter(mean value of Af~0.80) and lowest(Af~0.64) during the monsoon season.The regression analysis shows that both R eff and R m are dependent on coarse-mode aerosols.The relationship between the simultaneous measurements of daily mean aerosol optical depth at 500 nm(AOD500) and PM 2.5 mass concentration([PM2.5]) shows that surface-level aerosol mass concentration increases with the increase in columnar aerosol optical depth over the observation period.  相似文献   
586.
Viral nervous necrosis(VNN)has emerged to become a major problem in the culture of larval and juvenile marine fish worldwide.Bioactive phytochemicals isolated from commonly available medicinal plants are often screened for their efficacy in controlling fish viral diseases.Occurrence of newer viral strains and resistance to existing antiviral drugs are problems currently as-sociated with treatment of VNN,which necessitates looking for alternate sources for effective antiviral drugs.The aim of the present study was to screen antiviral potential of gymnemagenol(C30H50O4)previously extracted from leaves of Gymnema sylvestre.The fish nodavirus,grouper nervous necrosis virus(GNNV)in infected Sahul Indian Grouper Eye(SIGE)cell lines were used to study the antiviral activity of gymnemagenol under in vitro conditions.The susceptibility of the virus to gymnemagenol was confirmed by measuring the viral titre(TCID50 mL?1)in virus-infected SIGE cells every 24 h.Gymnemagenol at 20 μg mL?1 inhibited the prolifera-tion of GNNV to 53% at the end of the 6th d by inhibiting the proliferation of GNNV-infected SIGE cells.The viable SIGE cells were reduced to 47% as determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.The viral titre(TCID50 mL?1)was also reduced to log 2.8 at the end of the 7th d in gymnemagenol-treated SIGE cells after inoculated with GNNV when compared to untreated control SIGE cell viral titre(log 4.1).Based on our results it can be concluded that gymnemagenol could be used as an antiviral agent against GNNV infection.  相似文献   
587.
The Ca II K filtergrams from Kodaikanal Solar Observatory have been used to study solar activity.The images are dominated by the chromospheric network and plages.Programs have been developed to obtain the network and plage indices from the daily images as functions of solar latitude and time.Preliminary results from the analysis are reported here.The network and plage indices were found to follow the sunspot cycle.A secondary peak is found during the period of declining activity in both the indices.A comparison of network indices from the northern and the southern hemispheres shows that the former is more active than the latter.However such an asymmetry is not clearly seen in the plage index.  相似文献   
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590.
The results obtained from an investigation of suspended particulate matter in the metropolitan city of Lahore (Pakistan) are reported and analysed in this paper. X-ray diffraction studies of the airborne matter collected from various urban and suburban sites show that non-clay minerals such as quartz, calcite and albite are contained in most of the samples in almost comparable amounts. Chemical analysis of some samples was carried out for complementing the x-ray diffraction data. The amount of quartz in the samples of dusty areas was found to be an order of magnitude more than in the samples of relatively cleaner areas. As the dust particles of these compounds are poor substrate for promoting nucleation of ice in the atmospheric clouds, they are liable to stay steadily in the atmosphere as pollutants.A comparison of the results of the airborne particulates and the soil samples collected from various sites show that the sources of quartz, calcite and albite in the airborne matter are both local and remot  相似文献   
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