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41.
Present paper reports a method of preparing polymer composite electrolyte nanofiber mat using polyvinyl alcohol (PVA), ammonium
thiocynate (NH4SCN) salt, and aluminium oxide (Al2O3) nano particles based on electrospinning technique. Two-stage process of preparation of nanofibers, namely, preparation of
nano particles filled PVA electrolyte gel solution followed by its electrospinning has been used. The so obtained nanofibers
have been characterized by XRD, DSC, SEM, and Conductivity measurements. XRD patterns affirm the formation of nanocomposite
while SEM pictures reveal formation of fibers on a nano scale format (300–800 nm). Fibers of the electrolytes are seen to
be thermally stable. Ionic conductivity of electrolyte fiber is seen to improve in the presence of nano filler at room temperature
with a maximum at 5.31×10−3 Scm−1 for 4 wt% filler concentration, which is comparable to that for corresponding dried gel electrolyte films. 相似文献
42.
Harshida GAMIT Natarajan AMARESAN 《土壤圈》2023,33(1):49-60
Abiotic stresses are a significant factor that considerably limits plant growth and productivity. Methylotrophs are an essential group of bacteria that utilize volatile carbon compounds, are prolific colonizers of different plant parts, and play a vital role in plant growth promotion(PGP) under stress conditions.Numerous rhizospheric and phyllosphere methylotrophs have been reported to exhibit PGP activities with superior stress-tolerating capacity against drought,heavy metal, salinity, high and... 相似文献
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Three midstorage hydration-dehydration treatments viz., soaking, moisture equilibration and moist-sand conditioning followed by drying, each at varying durations for preservation of vigour and viability during storage in safflower var. K.1, were evaluated for their efficacy. Soaking seeds for 3 h followed by dehydration proved to be the best. Maintenance of membrane integrity and counteraction of lipid peroxidation may be the possible reasons for such advantage as evidenced by lower electrical conductance and peroxide values in the best treatment. 相似文献
46.
A. Rajendiran E. Natarajan P. Subramanian 《Journal of the World Aquaculture Society》2008,39(3):375-383
The present study describes the potential of black nightshade, Solanum nigrum , to control Aeromonas hydrophila infection in spotted snakehead, Channa punctatus . Similar sizes of Ch. punctatus were grouped into three categories as follows: control (injected with sterilized water), Ae. hydrophila infected + untreated, and Ae. hydrophila infected + treated with S. nigrum leaf extract. Hematological parameters (white blood cell [WBC], red blood cell [RBC], hemoglobin [Hb], and packed cell volume [PCV]) were analyzed in these fishes once every 5 d from Days 5 to 30 postexposure. Preliminary antibacterial assay reported that leaf extracted with ethyl acetate had the maximum inhibition compared to other parts of the plant (i.e., berries and whole plant) or when extracted with other solvent extracts (chloroform and ethanol). Except for WBC count, all other parameters showed a declining trend from Day 5 onward and reaching to a minimum on Day 30 in Ae. hydrophila -infected fish, whereas the WBC count increased. The infected fish treated with S. nigrum leaf extract reported a significant reversion to normal RBC, WBC, Hb, and PCV levels and the skin ulceration recovered within a short period. The antiulcer potential of the medicinal plant as described in humans may be extended to the fish population. 相似文献
47.
The anti-pyretic and anti-ulcerogenic properties of methanolic extract of Sida cordifolia aerial parts (MESC) were investigated in rats. Oral dose of 500 mg/kg MESC significantly reduced pyrexia induced by TAB vaccine. MESC exhibited significant anti-ulcerogenic effect against aspirin and ethanol induced damage. Both these properties were comparable to the reference drugs. 相似文献
48.
Marappan Jayanthi Peter Nila Rekha Natarajan Kavitha & Pitchaiyappan Ravichandran 《Aquaculture Research》2006,37(16):1617-1626
Aquaculture is one of the fastest growing food industries and the rapid growth of aquaculture worldwide has resulted in growing concerns about its impact on important ecosystems. Kolleru Lake, India's largest fresh water body, and Ramsar site have undergone tremendous changes due to the development of aquaculture. To assess the impact of aquaculture on Kolleru, satellite data were found appropriate because of the synoptic‐detailed overview and accuracy. Satellite data of IRS 1D, LISS III from 2004 and Survey of India topographic maps from 1967 were processed using image processing techniques in erdas imagine and analysed in Geographical Information System (GIS) such as arc gis 9.1. Land use map prepared from the satellite data was verified in the field using Global Positioning System to check the land and water use classes and its areal extent. It was estimated from the topographic maps of 1967 that the total lake boundary area was 180.38 km2, in which 70.70 km2 had water throughout the year and 100.97 km2 had water during the rainy season. The digital image processing of 2004 satellite data revealed that Kolleru was no longer a lake and the lake area of 62.65 km2 (34.73%) only remained in a degraded state, extensively colonized by macrophytes. The total loss of lake area was 109.02 km2 between 1967 and 2004, in which aquaculture was developed in 99.74 km2, which represented 55.3% of the 1967 lake area. The maximum conversion to aquaculture occurred from the lake liable to be inundated during the 1967 rainy season. The area under agriculture was 16.62 km2 in 2004, the increase in lake area for agriculture between 1967 and 2004 being 8.22 km2 (4.55% of lake). If human induced degradation is allowed to continue, the lake will very soon disappear. Now, the Government of Andhra Pradesh, India, has initiated schemes and laws to restore the lake to its pre‐development state. Lessons learnt from the Kolleru Lake cautioned that there is a need for regular monitoring of important water resources throughout the world to protect the biodiversity of the earth. 相似文献
49.
A decrease in the yield of chromosomal aberrations in root meristems of wheat induced by four different doses of x-rays has been found to occur when the seeds are pretreated with ultraviolet radiation. However, in X(2) generation, the mutation rate for combined treatment is lower than for x-rays alone in lower dosages and higher than for x-rays alone in higher dosages. 相似文献
50.
Lee J Natarajan M Nashine VC Socolich M Vo T Russ WP Benkovic SJ Ranganathan R 《Science (New York, N.Y.)》2008,322(5900):438-442
Statistical analyses of protein families reveal networks of coevolving amino acids that functionally link distantly positioned functional surfaces. Such linkages suggest a concept for engineering allosteric control into proteins: The intramolecular networks of two proteins could be joined across their surface sites such that the activity of one protein might control the activity of the other. We tested this idea by creating PAS-DHFR, a designed chimeric protein that connects a light-sensing signaling domain from a plant member of the Per/Arnt/Sim (PAS) family of proteins with Escherichia coli dihydrofolate reductase (DHFR). With no optimization, PAS-DHFR exhibited light-dependent catalytic activity that depended on the site of connection and on known signaling mechanisms in both proteins. PAS-DHFR serves as a proof of concept for engineering regulatory activities into proteins through interface design at conserved allosteric sites. 相似文献