42 research outputs found
CADMIUM CHLORIDE INDUCED CHANGES IN PROTEIN MOLECULES OF THE FRESHWATER FISH CIRRHINUS MRIGALA (HAMILTON)
Abstract                      The fresh water fish Cirrhinus mrigala (Hamilton) was exposed to the heavy metal Cadmium chloride for 24, 48, 72, and 96 h, and the consequential LC50 values were calculated using Finney's probit analysis. The LC50 values obtained for 24, 48, 72, and 96 h were 317.5, 316.5, 316.0 and 315.5 respectively. Later the fish were exposed to 96 h acute lethal and sub-lethal concentrations and the changes in protein subunits were analyzed in the tissue of the vital organs such as brain, liver, muscle, gill and kidney using SDS-PAGE electrophoresis. The results revealed that among the protein molecules some became faded when compared to control fish protein molecules, whereas some protein bands disappeared. The analysis was made with the help of standard protein marker. The changes are more pronounced in the tissue of liver and muscle, which may be due to the involvement of liver in the detoxification mechanism. Whereas in case of muscle the changes in the protein banding pattern may be due to the consumption of energy through erratic movement caused due to the toxicant stress. It was also observed that the changes in kidney protein molecules is also more and this may be due to the accumulation of cadmium chloride in kidney tissue. The results obtained were discussed at length with the available literature. Key words: Cadmium chloride, Cirrhinus mrigala, Protein molecules, Liver, LC50 and       SDS-PAGE
Effect of high-temperature heat treatment duration on the purity and microstructure of MWCNTs
The effect of high-temperature heat treatment on purity and structural changes of multiwalled carbon nanotubes (MWCNTs) were studied by subjecting the raw MWCNTs (pristine MWCNTs) to 2600∘C for 60 and 120 min. Thermogravimetric analysis (TGA), X-ray diffraction, Raman spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to study the effect of heat-treatment duration on the purity and structural changes of MWCNTs. Results show that high-temperature heat treatment can be used to purify MWCNTs with proper optimization of treatment time. It was observed that 60 min heat treatment of raw MWCNTs imparts high purity and structural perfection to MWCNTs, while 120 min heat treatment imparts structural degradation to MWCNTs with collapse of the innermost shells. The present study indicates that metal impurities act as moderators in controlling the degradation of MWCNTs up to certain duration, and once the metal impurities escape completely, further heat treatment degrades the structure of MWCNTs
DETERMINATION OF ORGANOCHLORINE PESTICIDE RESIDUES IN THE WATER OF PADDY FIELDS OF PRAKASAM DISTRICT, ANDHRA PRADESH, INDIA
Organochlorine (OC) pesticide residues in pooled water of paddy field samples of Prakasam District have been investigated to find out the extent of pesticide contamination and accumulation. Collected Water samples were processed using a liquid-liquid extraction followed by Gas-Chromatographic technique for pesticide residue quantification with mass selective detector (GC-MS). The conditions were followed for GC, Column: HP-5MS
SRI-A Method for Sustainable Intensification of Rice Production with Enhanced Water Productivity
Climate change induced higher temperatures will increase crops’ water requirements. Every 10°C increase
in mean temperature, results in 7% decline in the yield of rice crop. Hence, there is a need to develop water
saving technologies in rice which consumes more than 50% of the total irrigation water in agriculture. System
of Rice Intensification (SRI) is one such water saving rice production technology. Experiments were conducted
at different locations in India including research farm of Directorate of Rice Research (DRR), Hyderabad, during
2005-10 to assess the potential of SRI in comparison to normal transplanting/Standard Planting (NTP/SP) under
flooded condition. SRI recorded higher grain yield (6 to 65% over NTP) at majority of locations. Long term studies
clearly indicated that grain yield was significantly higher (12-23% and 4-35% over NTP in Kharif and Rabi seasons,
respectively) in SRI (with organic+inorganic fertilizers) while the SRI (with100% organic manures), recorded higher
yield (4-34%) over NTP only in the Rabi seasons. Even though, SRI resulted in higher productivity, the available
nutrient status in soil was marginally higher (10, 42 and 13% over NTP for N, P and K, respectively) at the end of
four seasons. There was a reduction in the incidence of pests in SRI and the relative abundance of plant parasitic
nematodes was low in SRI as compared to the NTP. About 31% and 37% saving in irrigation water was observed
during Kharif and Rabi seasons, respectively in both methods of SRI cultivation over NTP. SRI performed well and
consistently reduced requirement of inputs such as seed and water in different soil conditions. SRI method, using
less water for rice production can help in overcoming water shortage in future and it can also make water available
for growing other crops thus promoting crop diversificatio
Assessment of different methods of rice (Oryza sativa. L) cultivation affecting growth parameters, soil chemical, biological, and microbiological properties, water saving, and grain yield in rice–rice system
Field experiments were conducted at DRR farm located at ICRISAT, Patancheru, in sandy clay loam soils during four seasons, Kharif 2008, Rabi 2008–2009, Kharif 2009 and Rabi 2009–2010, to investigate growth parameters, water-saving potential, root characteristics, chemical, biological, and microbial properties of rhizosphere soil, and grain yield of rice (Oryza sativa L.) by comparing the plants grown with system of rice intensification (SRI) methods, with organic or organic + inorganic fertilization, against current recommended best management practices (BMP). All the growth parameters including plant height, effective tillers (10–45 %), panicle length, dry matter, root dry weight (24–57 %), and root volume (10–66 %) were found to be significantly higher with in SRI-organic + inorganic over BMP. With SRI-organic fertilization, growth parameters showed inconsistent results; however, root dry weight (3–77 %) and root volume (31–162 %) were found significantly superior compared to BMP. Grain yield was found significantly higher in SRI-organic + inorganic (12–23 and 4–35 % in the Kharif and Rabi seasons, respectively), while with SRI-organic management, yield was found higher (4–34 %) only in the Rabi seasons compared to BMP. An average of 31 and 37 % of irrigation water were saved during Kharif and Rabi seasons, respectively, with both SRI methods of rice cultivation compared to BMP. Further, total nitrogen, organic carbon%, soil dehydrogenase, microbial biomass carbon, total bacteria, fungi, and actinomycetes were found higher in the two SRI plots in comparison to BMP. It is concluded that SRI practices create favorable conditions for beneficial soil microbes to prosper, save irrigation water, and increase grain yield
Mechanical, thermal and ablative properties of zirconia, CNT modified carbon/phenolic composites
Zirconium oxide (Zirconia) coating on carbon fabric (C-fabric) was developed by using zirconia sol. C-fabrics having different weight percentages (wt%) of zirconia namely 0 wt% (Blank), 3.5 wt%, 6.5 wt% and 9.5 wt% were used to make Zirconia–Carbon–Phenolic (Zr–C–Ph) composites. Similarly, 0.5 wt% multiwalled carbon nanotube (CNT) dispersed phenolic resin was used to make CNT–C–Ph composite. Thermal conductivity, ILSS and flexural strength were measured for the prepared composites. Based on the initial results, subsequently a functionally graded carbon–phenolic composite (FG-C–Ph) having CNT–C–Ph composition up to certain thickness followed by Zr–C–Ph composition for the remaining thickness was made. Thermal insulation and ablative properties for blank C–Ph, Zr–C–Ph, FG-C–Ph were studied using plasma arc jet test which was carried out at a heat flux of 4.0 MW/m2 for 30 s. Results from the plasma arc jet test show that, the temperature drop across the Zr–C–Ph composite was found to be highest while it was least for the blank. However the ablation rate was found to be highest for the FG-C–Ph while it was least for the blank. Ablation mechanisms for all the tested composites are proposed based on the SEM and XRD studies