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71.
S. K. Gupta Anamika Tewari Richa Srivastava R. C. Murthy Saurabh Chandra 《Water, air, and soil pollution》2005,163(1-4):293-302
Vermicomposting of fly ash has been attempted, using red earthworm, Eisenia foetida. Fly ash, which was obtained from thermal power station, was mixed with cowdung in different proportions (20, 40, 60 and 80%). These mixtures were used as feed for earthworms, and after 30 days, vermicast recovery, worm zoomass and numbers of juveniles produced were recorded. A total of six runs each of 30 days were conducted during the whole study. Concentrations of heavy metals in different mixtures of fly ash–cowdung, before and after vermicomposting and in the earthworms used in the study were also estimated. Results show maximum output of vermicasts and maximum number of juveniles produced was in reactors with 40% fly ash while maximum weight gain by earthworm was in 20% fly ash vermireactors. Performance of vermireactors up to 60% fly ash was more or less similar but at 80% fly ash, there is a marked reduction in overall performance of the reactors. Chemical analysis of different samples of fly ash–cowdung mixtures prior to vermicomposting revealed high concentrations of zinc, chromium, lead, nickel and copper. Chemical analysis of vermicomposted samples showed 30–50% reduction in heavy metals up to 60% fly ash and 10–30% reduction in 80% fly ash. Metal analysis of earthworms revealed considerable bioaccumulation of heavy metals in their body. The Present study indicates the feasibility of E. foetida for mitigating the toxicity of metals and up to 60% fly ash–cowdung mixtures can be used for sustainable and efficient vermicomposting. 相似文献
72.
Abhik Gupta 《Water, air, and soil pollution》1995,82(3-4):751-756
Comparisons were made of the accumulation of cadmium, copper, manganese, lead, and zinc in Plagiothecium denticulatum, Bryum argenteum and Sphagnum sp. in Shillong, Meghalaya State, Northeastern India. Samples of P. denticulatum and B. argenteum were collected inside Shillong city (urban) and its immediately adjacent outskirts (suburban), while Sphagnum sp. was collected from a suburban site only. Lead and copper levels were higher in P. denticulatum, while Sphagnum sp. accumulated higher amounts of zinc, manganese, and cadmium. An urban-suburban gradient was evident for lead and zinc in P. denticulatum, and for cadmium in B. argenteum, while a reverse trend could be discerned for manganese in P. denticulatum. Besides vehicles and minor industries, quarry dust was likely to be an important source of manganese, copper, and zinc. 相似文献
73.
To simplify the analysis of stress over a cultivator shovel moving at a certain depth, it was represented by an isosceles triangular plate of uniform thickness. To simulate the boundary conditions to which a cultivator shovel is subjected, the triangular plate was assumed as clamped along one of the edges while the other two edges were assumed as free. These assumptions made it possible to apply the theory of bending of laterally loaded plates for the computation of stresses set up in the tillage tool. This theory involves fundamental equations of elasticity, namely the equations of equilibrium, equations of continuity and surface conditions. The theoretically calculated values of stresses were fairly close to experimentally observed values. 相似文献
74.
Mukesh Bhakat Tushar K. Mohanty Ashok K. Gupta Virendra S. Raina Biswajit Brahma R. K. Mahapatra M. Sarkar 《Tropical animal health and production》2010,42(7):1363-1366
Effect of Foot and Mouth disease (FMD) vaccination was studied on semen quality parameters of 19 Karan Fries (KF) and eight
Murrah (MU) breeding bulls during the period 2002 to 2004 at Artificial Breeding Complex, NDRI, Karnal. A total of non-vaccinated
155 KF and 72 MU bulls' ejaculates were taken as control, while 169 KF and 51 MU bulls' ejaculates, collected after vaccination,
were used to study the effect of vaccination stress. The results showed that FMD vaccination had no significant (P > 0.05) effect on ejaculate volume and total volume per day of semen in both KF and MU bulls. Volume of semen increased slightly
during post-vaccination period in both the breeds. After FMD vaccination, there was significant (P < 0.01) decrease in mass activity (2.27 ± 0.06 vs. 1.67 ± 0.07 and 2.49 ± 0.09. vs. 1.75 ± 0.10, for KF and MU, respectively),
initial motility (56.89 ± 0.03% vs. 44.62 ± 0.02% and 62.26 ± 0.04% vs. 47.08 ± 0.05%, for KF and MU, respectively), sperm
concentration (754.19 ± 23.96 vs. 554.14 ± 22.95 × 106/ml and 848.61 ± 33.65 vs. 571.57 ± 39.99 × 106/ml, for KF and MU, respectively), and total sperm output per ejaculate (3,685.94 ± 158.40 vs. 2,781.54 ± 151.70 × 106 and 2,218.75 ± 133.14 vs. 1,582.84 ± 158.20 × 106, for KF and MU, respectively). Application of FMD vaccine had significantly (P < 0.05) adverse effect on most of the seminal attributes during post-vaccination in KF and MU buffalo bulls. So, the spermiograms
affected following vaccination suggest that in bovines, the semen collection and preservation should be suspended till normal
fertility of sperm is restored to avoid the failure of conception from artificial insemination using such semen. 相似文献
75.
Kwasi Bannor Richard Amarnath Krishna Kumar Gupta Oppong-Kyeremeh Helena Abawiera Wongnaa Camillus 《水稻科学》2020,27(1):56-66
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17. 相似文献
76.
Rishi Raj Anil Kumar I. S. Solanki Shiva Dhar Anchal Dass Ashish Kumar Gupta Vikash Kumar C. B. Singh R. K. Jat U. C. Pandey 《Paddy and Water Environment》2017,15(4):861-877
A field study on assessment of crop establishment methods on yield, economics and water productivity of rice cultivars under upland and lowland production ecologies was conducted during wet seasons (June–November) of 2012 and 2013 in Eastern Indo-Gangetic Plains of India. The experiment was laid-out in a split-plot design (SPD) and replicated four times. The main-plot treatments included three crop establishment methods, viz. dry direct-seeded rice (DSR), system of rice intensification (SRI) and puddled transplanted rice (PTR). In sub-plots, five rice cultivars of different groups like aromatic (Improved Pusa Basmati 1 and Pusa Sugandh 5), inbreds (PNR 381 and Pusa 834) and hybrid (Arize 6444) were taken for their evaluations. These two sets of treatments were laid-out simultaneously in two production ecologies, upland and lowland during both years. In general, lowland ecology was found favourable for rice growth and yield and resulted in 13.2% higher grain yield as compared to upland ecology. Rice grown with SRI method produced 19.4 and 7.0% higher grain yield in 2012 and 20.6 and 7.1% higher in 2013, over DSR and PTR. However, PTR yielded 13.1 and 14.5% higher grain over DSR during 2012 and 2013, respectively. On an average, Arize 6444 produced 26.4, 26.9, 28.9 and 54.7% higher grain yield as compared to PS 5, P 834, PNR 381 and IPB1, respectively. Further, the interaction of production ecologies × crop establishment methods revealed that, in upland ecology, SRI recorded significantly higher grain yield as compared to PTR and DSR, but in lowland, grain yield resulting from SRI was similar to the yield obtained with PTR and significantly higher than DSR. The latter two methods (PTR and DSR) yielded alike in lowland ecology in both study years. The production ecologies × crop establishment methods × cultivars interaction on grain yield showed that the growing of Arize 6444 cultivar using SRI method in upland ecology resulted in the higher grain yield (8.87 t/ha). But the cost of production was also highest in SRI followed by PTR and DSR across production ecologies and cultivars. Cultivation of hybrid (Arize 6444) involved higher cost of production than all other cultivars. Irrespective of crop establishment methods and cultivars, gross returns, net returns and B:C ratio were significantly higher in lowland compared to upland ecology. Owing to higher grain yield, SRI method fetched significantly higher gross returns and net returns over PTR and DSR. Average increase in net return with Arize 6444 was 68.8, 41.0, 37.7 and 33.1% over IPB 1, PNR 381, P 834 and PS 5, respectively. There was a saving of 30.7% water in SRI and 19.9% in DSR over PTR under upland ecology. Similarly in lowland ecology, water saving of 30.2% was observed in SRI and 21.2% in DSR over PTR. Due to higher yield and saving on water, SRI returned significantly higher total water productivity (TWP) (5.9 kg/ha-mm) as compared to DSR (3.5 kg/ha-mm) and PTR (3.6 kg/ha-mm) under upland ecology. In lowland ecology, also SRI (6.2 kg/ha-mm) resulted in higher TWP as compared to other two methods. However, DSR gave significantly higher TWP as compared to PTR. Among cultivars, hybrid Arize 6444 recorded the highest TWP in both upland and lowland production ecologies across crop establishment methods. Hence, growing of hybrid Arize 6444 with SRI method can enhance rice productivity and water-use efficiency in lowland and upland production ecologies of Eastern Indo-Gangetic Plains and in other similar regions. 相似文献
77.
The isolation of 7,4'-dihydroxy-8-methylflavan (1) from the dichloromethane extract of Pancratium littorale stem was guided by an assay for free radical scavenging activity towards the 2,2-diphenyl-1-picryl-hydrazyl radical (DPPH). The structure of 1 was established by spectrometric methods including UV, EI mass spectrometry, 1H and 13C-NMR. The free radical scavenging properties of 1 were quantified in solution using spectrophotometry. 相似文献
78.
79.
We demonstrate the ability to measure the energy required to flip the spin of single adsorbed atoms. A low-temperature, high-magnetic field scanning tunneling microscope was used to measure the spin excitation spectra of individual manganese atoms adsorbed on Al2O3 islands on a NiAl surface. We find pronounced variations of the spin-flip spectra for manganese atoms in different local environments. 相似文献
80.
The effect of serum from horn cancer affected bullocks and cows on E-rosetting capacity of peripheral blood lymphocytes (PBL) from unaffected control animals was examined. The E-rosette counts were made using 2-aminoethyl isothiouronium bromide (AET) treated sheep red blood cells. A significant decrease in the percentage of EAET rosette forming cells was noticed when PBL were incubated with 50 per cent serum from animals affected with horn cancer. However, no such effect was noticed when PBL were treated with 50 per cent serum from unaffected control animals. A linear relationship was observed between percentage of EAET rosette forming cells of animals affected with horn cancer and E-rosette inhibitory activity of the corresponding serum on PBL from control animals. 相似文献