Search

Composites of metal oxide with carbonaceous materials have attracted researchers due to their high energy density and high power density. A series of tin (Sn) incorporated nickel oxide/carbon nanotube (NiO/CNT) composites are prepared by simple microwave irradiation. The chemical composition of prepared composites is analysed using various analytical techniques such as powder x-ray diffraction, micro-Raman spectroscopy, and x-ray photoelectron spectroscopy. Surface morphological studies of the composites revealed that the prepared composite has a uniform mixture of NiO nanoflakes with carbon nanotubes. Electrochemical studies of the composite electrodes in a three-electrode system demonstrate that 3% Sn-doped NiO/CNT composite has a higher specific capacitance of 238.2 F/g @ 5 mV/s scan rate than the specific capacitance of 231.8, 214.4 and 160.2 F/g @ 5 mV/s attained for 5%, 1% Sn-doped NiO/CNT and pristine NiO/CNT, respectively, in 2M potassium hydroxide (KOH) electrolyte. A high specific capacitance of 239.0 F/g @ 1 A/g current density is achieved for 3% Sn-doped NiO/CNT in galvanic discharge studies indicates that the prepared Sn-doped NiO/CNT is a suitable candidate for electrochemical supercapacitors.

The dynamics of methane emission and its associated soil microflora in rice ecosystem as a response to elevated CO2 concentrations were studied in open top chamber (OTC) conditions. The treatments consisted of three levels of CO2 (396, 550 and 750 µmol mol-1) and three levels of nitrogen (0, 150 and 200 kg ha-1) and replicated five times in a completely randomized design. The data showed that elevated [CO2] significantly (P ? 0.01) increased the DOC throughout the cropping period with the values ranging from 533 to 722 mg L-1 and 368 to 501 mg L-1 in C750 and Camb, respectively. Methane emission rates were monitored regularly during the experiment period and it was revealed that elevated [CO2] had increased the methane emissions regardless of stages of crop growth. It was observed that methane emissions were significantly higher under [CO2] of 750 µmol mol-1 by 33 to 54 per cent over the ambient [CO2] of 396 µmol mol-1. Consistent with the observed increases in methane flux, the enumeration of methanogens showed a significant (P ? 0.01) increase under elevated [CO2] with the population ranging from 5.7 to 20.1 x 104 CFU g-1 of dry soil and 5.1 to 16.9 x 104 CFU g-1 of dry soil under C750 and Camb concentrations, respectively. Interestingly, even though higher methanotrophs population was recorded under elevated [CO2], it could not circumvent the methane emission. Overall, the results of OTC studies suggest that methane mitigation strategies need to be explored for the future high CO2 environments.

Aim: To study the influence of elevated atmospheric CO2 concentrations on the carbon and nitrogen assimilation patterns in rice plants. Methodology: Rice (Oryza sativa) plants were placed in Open Top Chambers (OTCs) and exposed to elevated levels of CO2. The treatments consisted of three levels of CO2 (398, 550 and 750 µmol mol-1) and three levels of nitrogen (0, 150 and 200 kg ha-1) and replicated five times in completely randomized design. Results: Leaf nitrogen was significantly reduced by 10.6 % and 6.5 % during later stages in rice plants exposed to CO2 @ 750 µmol mol-1 and 550 µmol mol-1, respectively over the ambient CO2. Rice plants under elevated CO2 did not exhibit any variations in Nitrate Reductase activity in leaves in comparison to ambient CO2 at tillering stage. Interestingly, NRase activity in leaves decreased at flowering stage whereas NRase activity in roots increased at same stage. The highest mean nitrogen values (0.58, 0.89 and 1.35 %) were observed in Camb (ambient CO2 concentration) and the lowest values (0.51, 0.80 and 1.27 %) in C750 in roots, straw and grains, respectively. Elevated CO2 @ 750 µmol mol-1 significantly increased the above ground biomass (straw and grain) by 15.6 and 40.1 %, respectively, over the ambient CO2 of 398 µmol mol-1. Interpretation: Elevated CO2 enhanced the grain productivity but affected the quality of rice grains. Thus, excessive nitrogen fertilization above the current recommendation is necessary for future high CO2 environments.

The coconut-based agricultural wastes have gained wide attention as an alternative adsorbent for the removal of diverse pollutants from the industrial effluents. This paper presents the zinc chloride activation of adsorbent carbon and the utilization as an adsorbent for the removal of malachite green dye from aqueous solution. The characterisation of activated carbon was performed to get an insight into the adsorption mechanism. The ZnCl2 activated carbon acquired a higher specific surface area (544.66 m2 g−1) and stability (−32.6 mV). The impact of process parameters including contact time (20–220 min) and initial dye concentration (20–80 mg L−1) were evaluated on the effectiveness of activated carbon for dye removal. The results concluded that zinc chloride activated carbon showed a significant dye adsorption (39.683 mg g−1) at an initial concentration of 20 mg L−1 after 3 hours. Based on the correlation coefficient (R2), the Freundlich isotherm model (0.978–0.998) was best fitted for the experimental data followed by the intraparticle diffusion model (0.88–0.929) as the most appropriate model for malachite green dye removal. Additionally, the energy and thermogravimetric analysis portrayed the suitability of the carbon material to be used as an energy alternative to coal.

The present study investigates the characterization of different coconut based low cost adsorbents like coconut shell biochar, zinc chloride impregnated coconut shell activated carbon, coir fibre and coir geotextile and their suitability characteristics as a filter bed in different wastewater treatment process. The characterization study helps to investigate their physical, chemical and morphological properties like proximate and ultimate analysis, iodine number, decolorizing power, SEM, Surface area using BET, Particle size and Zeta potential. The experiment results showed that among the different adsorbents activated carbon has high fixed carbon content (82.99 percent), more surface area (590.8 m2 g-1), low ash content (1.31 percent) with a decolorizing power of 240-300 mg g-1. The coir fibre and coir geotextile having neutral pH with negative surface charge easily adsorbs the positive cations from aqueous solutions at highest apparent density. The experimental findings suggest that the activated adsorbent which shows better results as an effective filter media for adsorption of organic compounds and pollutants from wastewater.

Activated carbon produced from coconut shells has been gaining interest in wastewater treatment as a potential carbon source for adsorption with desired porosity, surface area, and stability requir...

Ozone stress identification in crops through remote sensing is a promising technology that has a major role in predicting stress-related physiological response. The spectral reflectance approach to phenotyping of rice cultivars is a non-destructive and accurate method to assess ozone stress. In this study, the leaf spectral reflectance of 15 rice cultivars was explored to evaluate the photosynthetic capacity under elevated ozone stress. Ozone injury percentage (OIP), a common indicator to identify ozone stress of rice leaves combined with leaf spectral signatures was used to identify the best fit spectral indices. The normalized difference spectral index (NDSI) was used to determine significant wavebands that showed the best correlation with leaf ozone injury. The correlation coefficient (r) between NDSI and OIP were ranged from -0.79 to 1. Normalized difference spectral index, NDSI[R564,R568], and NDSI[R558,R573] were identified as the best Pearson's correlation with leaf ozone injury percentage with correlation coefficient more than 0.96. The evaluated NDSI in visible regions were identified as a sensitive region to ozone injury. Additionally, results were compared with previously established indices and also evaluated for correlation with plant physiological traits. The correlation coefficient of determination (R2) > 0.5 was observed for newly developed spectral indices, NDSI[R564,R568] and NDSI[R558,R573] with physiological traits compared to previously established 20 indices. The highest R2 of 0.674 were observed for the spectral index, NDSI[R558,R573] with photosynthetic rate and R2 of 0.673 for NDSI[R564,R568] with relative chlorophyll content. As a result, the current research has implications for the selection of the best capable spectral regions for early detection of ozone stress in rice cultivars without destructing the crop. The outcome of the present work suggests that newly developed spectral indices could assist in remote sensing technology in monitoring large scale ozone stress and crop modeling studies to ensure food security.

Agricultural soils are responsible for formation of N2O through nitrification and denitrification processes. Nitrification inhibitors reduces the rate at which ammonium is converted to nitrate either by killing or interfering with the metabolism of nitrifying bacteria. Synthetic nitrification inhibitors can efficiently inhibit nitrification. The present study was undertaken to observe the effect of Potassium thiosulfate (PTS) and neem coated urea on N2O efflux under irrigated tomato cultivation to assess its suitability for decreasing N2O emission to the atmosphere. The results depicted the reduction of nitrate nitrogen on third day after fertilizer application compared to zeroth day. The decreased NO3-N was mainly due to the uptake by tomato for its growth and converted into N2O as intermediate product during nitrification process. The yield of tomato (fruit yield) was significantly increased due to the application of various doses and types of N fertilizer application along with N inhibitors. The highest yield (63.2 t ha-1) was recorded with the soil application of nutrients in STCR based recommendation of NPK with Neem coated urea which was on par with the STCR based recommendation of NPK with Normal urea (183:160:125kg ha-1) along with Potassium thiosulfates @ 1% of applied N whereas blanket recommendation of NPK application recorded lower yield. The 38% lowest N2O emission was found in the STCR based recommendation of NPK with Normal urea with Potassium thiosulfates @ 1% of applied N compared to Blanket recommendation of NPK with Normal urea, which was on par with the treatment of STCR based recommendation of NPK with Neem coated urea.

The conversion of atmospheric CO 2 into stable long lived carbon pools is an important phenomenon of soil carbon sequestration. Cocoa cultivation significantly increased the slow and passive carbon pools of soil. Significant increase in the organic fractions like humic acid, fulvic acids, non-humic and humin were observed in seven years cocoa cultivated soils. The organic matter fractions were significantly high during January and there after a decrease in trend were registered for all the three soils. A field study was carried out in the cocoa plantations of Moorje, Bantwal taluka, Dakshinakannada district, Karnataka. This study was carried out in five and seven years cocoa plantations in comparison with non-cocoa plantations.

Shoot-tip derived callus cultures of Sorghum bicolor were transformed by Agrobacterium tumefaciens as well as by bombardment methods with the mutated pyrroline-5-carboxylate synthetase (P5CSF129A) gene encoding the key enzyme for proline biosynthesis from glutamate. The transgenics were selfed for three generations and T4 plants were examined for 100 mM NaCl stress tolerance in pot conditions. The effect of salt stress on chlorophyll and carotenoid contents, photosynthetic rate, stomatal conductance, internal carbon dioxide concentration, transpiration rates, intrinsic transpiration and water use efficiencies, proline content, MDA levels, and antioxidant enzyme activities were evaluated in 40-day-old transgenic lines and the results were compared with untransformed control plants. The results show that chlorophyll content declines by 65% in untransformed controls compared to 30–38% loss (significant at P < 0.05) in transgenics but not carotenoid levels. Photosynthetic rate (PSII activity) was reduced in untransformed controls almost completely, while it declined by 62–88% in different transgenic lines. Salinity induced ca 100% stomatal closure in untransformed plants, while stomatal conductance was decreased only by 64–81% in transgenics after 4 days. The intercellular CO2 decreased by ca 30% in individual transgenic lines. Malondialdehyde (MDA) content was lower in transgenics compared to untransformed controls. The activities of superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6) and glutathione reductase (GR; EC1.8.1.7) were quantified in leaves exposed to 100 mM NaCl stress and found higher in transgenics. The results suggest that transgenic lines were able to cope better with salt stress than untransformed controls by protecting photosynthetic and antioxidant enzyme activities.

Nitrogen (N) is one of the most important nutrients required for crop production. Application of fertilizer N results in increased growth and higher biomass yields. It directly influences the amino acid composition of protein and thereby nutritional quality of the economic produce. Effects of N fertilization are different in different crops. In cereals, it affects the proportion of amino acids lysine and threonine. Kernel quality and strength increases with increased N which in turn positively affects the milling properties. In oil seeds protein content increases, but has an adverse effect on oil content. Vegetables show varied effects. High N levels produce the firmest fruit with the highest total soluble solids and dry matter content. In fruits, nitrogen affects several quality aspects such as size, shape, color, texture, flavor, and composition. In this chapter, we discuss the effects of N fertilization on crop quality of major crops including food, oilseed, horticultural, and fodder crops. In general, in horticultural crops large amounts of fertilizers are being used to maintain high production levels of quantity and quality. Nitrogen in excess quantities is also toxic and can have adverse effects on the quality of the economic produce. Strategies to increase the crop nitrogen use efficiency, which is low at present, and simultaneously enhance the crop quality are of urgent priority. Understanding the role of nitrogen and its metabolic interaction in crops is an important step toward increasing productivity without compromise on quality. An attempt has been made to outline the effect of N nutrition on crop quality with emphasis on present strategies and future perspectives.

Sunflower ( Helianthus annuus L.) and maize (Zea mays L.) were chosen as C 3 and C 4 crop plants and assessed for the impact of enhanced CO 2 (700 ppm) and its interaction with drought stress in open top chambers (OTCs). The ameliorative effect of higher CO 2 concentration (eCO 2 ) under drought stress was quantified. It is interesting to note that the C 3 crop responded significantly and positively with eCO 2 under both well-watered and drought stress treatments for root: shoot ratio while C 4 crop showed a better response only with the drought stress environment. Root volume showed a positive significant response with CO 2 concentration enhanced over ambient level and the increment in root volume was 146% and 340% in sunflower and maize crops, respectively. The leaf water potential, stomatal conductance and transpiration showed a decreasing trend in both the crops with drought stress and eCO 2 showed an ameliorative effect leading to higher P n rates in sunflower crop under drought stress treatment. The findings reveal that improvement of root traits is worth attempting for the future crop behavioral responses under eCO 2 and drought stress environments. The study confirmed the beneficial effect of eCO 2 in maize and sunflower by ameliorating the adverse affects of drought stress.

The response of blackgram ( Vigna mungo L. Hepper) to two levels of elevated carbon dioxide (550 and 700 ppm) in terms of growth and yield was investigated and compared with ambient CO 2 level (365 ppm) using open-top chambers. The growth parameters viz., length and weight of root and shoot, root:shoot ratio, leaf area and weight significantly increased at 700 ppm CO 2 when compared with 550 ppm. The percentage increase in total biomass at 700 and 550 ppm CO 2 was 65.4% and 39%, respectively compared to the ambient (chamber) control. The increase in total seed yield at 700 ppm (129%) was due to an increase in number of pods per plant and 100 seed weight, whereas at 550 ppm (88.7%) it was due to an increased number of pods/plant and seeds/pod. The results indicate variable responsive effects at different levels of CO 2 emphasizing the pertinence of research on elevated CO 2 in various agroecological inhabitations all over the world. The indication of higher responses for root and leaf at initial growth stages at the higher elevated level of CO 2 (700 ppm), which leads to better root establishment, achieving early photosynthetic efficiency and also better biomass production, and its improved partitioning can be reckoned as a positive aspect of increasing concentrations of CO 2 in atmosphere. The harvest index increased significantly to 35.7 and 38.4% at 550 and 700 ppm, respectively; it is a very important phenomenon in pulses for breaking the yield barrier.

An efficient and rapid regeneration protocol was developed using shoot apices from germinating seedlings of two cultivars of sorghum, SPV-462 and M35-1, as explants. A vertical slit given from the base of each dissected apex enhanced the efficiency of callusing response by two fold. MS medium containing 0.5 mg dm−3 each of 2,4-D and kinetin was most effective in producing friable and embryogenic calli. Scanning electron microscopy of these calli detected somatic embryogenesis. Calli thus induced gave rise to approximately 42 green shoots per callus in both the genotypes when transferred to regeneration medium containing 1.5 mg dm−3 kinetin.

The effects of equilibration under different air relative humidities (RH, 1 - 90 %) and temperatures (35 and 45 °C) on soybean (Glycine max) and wheat (Triticum aestivum) seeds were studied using different techniques. Seed moisture content, electrical conductivity (EC) of seed leachate and per cent seed germination were measured following standard procedures, and compared with nuclear magnetic resonance spin-spin relaxation time (T2) measurements. Moisture contents of soybean and wheat seeds, following the reverse sigmoidal trend, were greater at 35 than at 45 °C at any particular RH. Changes in T2 were related to the changes in germination percentage and leachate EC of both soybean and wheat seeds. Equilibrating soybean seeds at RH ≤ 11 % decreased germination percentage with corresponding decrease in T2. On the contrary, EC of seed leachate increased. In wheat seeds equilibrated at 45 °C, T2 was maximal at RH 5.5 %. T2 declined in seeds equilibrated at high RH (> 80 %) together with low germination percentage.

The present investigation was undertaken with an objective of formulating mouth dissolving films (MDFs) of Amlodipine Besylate (AMLO) to enhance convenience and compliance of the elderly and pediatric patients for better therapeutic efficacy. Film formers like hydroxy propyl methyl cellulose (HPMC) and methyl cellulose (MC) along with film modifiers like poly vinyl pyrrolidone K30 (PVP K30), and sodium lauryl sulphate (SLS) as solubilizing agents were evaluated. The prepared MDFs were evaluated for in vitro dissolution characteristics, in vitro disintegration time, and their physicomechanical properties. All the prepared MDFs showed good mechanical properties like tensile strength, folding endurance, and % elongation. MDFs were evaluated by means of FTIR, SEM, and X-RD studies. MDFs with 7.5% (w/w) of HPMC E3 gave better dissolution properties when compared to HPMC E5, HPMC E15, and MC. MDFs with PVP K30 and SLS gave superior dissolution properties when compared to MDFs without PVP K30 and SLS. The dissolution properties of MDFs with PVP K30 were superior when compared to MDFs with SLS. In the case of F3 containing 7.5% of HPMC E3 and 0.04% of PVP K30, complete and faster release was observed within 60 sec when compared to other formulations. Release kinetics data reveals diffusion is the release mechanism.

The present investigation includes the preparation of liquid filling formulations for soft gels using an antihypertensive drug, valsartan (VAL), in order to improve its dissolution properties and thereby its bioavailability. Formulations were prepared using excipients like polyethylene glycol 400 (PEG 400), propylene glycol (PG), polyvinylpyrrolidone (PVP K-30), antioxidants, ethanol, and purified water. Prepared formulations were evaluated for appearance, pH, drug content percentage, viscosity, stability, and in vitro dissolution studies. The compatibility between the drug and excipients in formulations was confirmed by FTIR spectra. The drug contents were in the range of 99.62-99.63 and the viscosity was in the range of 60.9–591.7 cps with all the formulations developed. Formulations containing 10 mg PVP K 30 gave better dissolution properties when compared to formulations without PVP K 30, and a complete drug dissolution was observed within 10 min and followed the first-order release kinetics. Stability studies were conducted for selected formulations (F4–F9) for a period of 6 months at room temperature (~30°C/65% RH). From the studies, it can be concluded that VAL liquid filling formulations for soft gels were successfully prepared with in vitro dissolution properties superior when compared to VAL itself.

Water stress effects on accumulation of dry matter, carbon and nitrogen in grains were analysed in varieties and species of wheat differing in yield stability. Variable water environments were generated using a line source sprinkler system. Although large fluctuations occurred in the water potentials of the flag leaf and ear, grain growth remained relatively buffered under moisture stress. Developing grains were at a lower moisture level throughout grain growth in plants subjected to moisture stress relative to the unstressed plants. Carbon content decreased more than the nitrogen content in the stressed grains of the species and varieties. Reduction in the duration of grain growth and the rate of dry weight accumulation induced by water stress was more prominent in T. aestivum var. C306 and T. sphaerococcum . Grain yield was reduced significantly under water stress, the maximum being in the high yielding cultivar HD2329. Both grain number and grain weight were reduced in response to stress, the extent of reduction being different in different genotypes.

The pattern of free NH 4 + accumulation and its metabolism was studied during the growth and development of field-grown wheat cv. HD 2204 at two applied N levels viz. 30 and 120 kg ha -1 . The study was confined to the 3rd, 5th and flag leaf blades and the developing ears, borne on the main shoot, during their ontogeny. The NH 4 + levels were considerably lower in young leaves and increased sharply as the leaves senesced when the activity of glutamine synthetase (GS) declined. In contrast to GS, glutamate dehydrogenase (GDH) remained active even during senescence. Concentrations of protein, free amino acid and total reduced N declined with age in the leaves. An assessment of free NH 4 + pool, free amino acid content and the activity of GS and GDH in the floral parts revealed that glumes, awns and grains also were active sites of NH 4 + turnover. Higher applied N level not only increased leaf and grain N concentration but also led to higher free NH 4 + levels in leaves and in developing ears. Presence of NH 4 + in the entrapped transpirate revealed that NH 4 + is released from both leaves and ears during senescence.

Performance of upflow anaerobic sludge blanket and upflow anaerobic hybrid reactor in treatment of distillery spentwash was investigated under similar operating conditions. The reactors were initially fed with distillery spentwash having an average COD concentration of 1,22,000 mg L–1 with a HRT of 10 days and their performance was evaluated by operating at various HRTs viz., 10, 8, 7, 6, 5 and 4 days. Among the various HRTs, six days HRT was found to be ideal for the maximum reductions of COD, BOD and TS by 63.26, 70.80 and 57.20% respectively at OLR of 19.75 kg COD m–3 day–1 with UASB and 70.60, 78.50 and 62.45% at OLR of 19.25 kg COD m–3 day–1 with UAHR. The biogas yield of 0.30 and 0.31 m3 kg–1 COD removed was recorded in UASB and UAHR. Population of total anaerobic bacteria and methanogenic bacteria are also high in UAHR than in UASB. The study concludes that upflow anaerobic hybrid reactor is superior in reducing the pollution load of distillery spentwash as compared to UASB.

Glutamine synthetase activity was found to be several fold higher in the leaves of a few C3 as compared to C4 plants. Differences in NH4+ levels were marginal. Methionine sulphoximine inhibition of glutamine synthetase resulted in increased in NH4+ levels more in wheat than in sorghum. The decrease in methionine sulphoximine induced accumulation of free NH4+ by photorespiratory inhibitors, isonicotinic acid hydrazide and α-hydroxy methane pyridine sulphate was also several fold higher in wheat than in sorghum. Feeding of glycine and glycolate, intermediates of photorespiration, showed the presence of active glycine decarboxylation system in sorghum but the metabolism of glycolate was more efficient in wheat. Higher glutamine synthetase activity in C3 plants may be a necessary adaptation to a higher photorespiratory NH4+ production and explain the similar or higher N losses in C4 as compared to C3 plants. These results also support the hypothesis that glutamine synthetase is important in the assimilation of photorespiratory ammonia.