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11.
Laluraj CM Krishnan KP Thamban M Mohan R Naik SS D'Souza W Ravindra R Chaturvedi A 《Environmental monitoring and assessment》2009,149(1-4):377-383
The scanning electron microscopy-energy dispersive spectroscopic (SEM-EDS) study of selected samples from an ice core collected from Central Dronning Maud Land (CDML), East Antarctica, revealed several microparticles. They are mainly siliceous and carbonaceous particles and have distinct variations in their shape and composition. The morphology and major element chemistry of the particles suggest their origin from either volcanic eruptions or continental dust. The EDS analysis revealed that the volcanic particles are enriched in silica (average SiO2 62%), compared to the continental dust particle (average SiO2 56%). We found that the tephra relating to Agung (1963) and Karkatau (1883) volcanic eruptions, as recorded, in the ice core harbored microbial cells (both coocoid and rods). The occurrence of organic and inorganic particles which bear relation to volcanic eruption and continental dust implies significant environmental changes in the recent past. 相似文献
12.
Chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridylphosphorothioate) is one of the organophosphate pesticides widely used in agricultural practices throughout world and irreversible inhibitor of cholinesterase in all animal species. Limited efforts have been made to study acute genotoxic effects of chlorpyrifos (CPF) in different tissues of fish using genotoxic biomarkers. Therefore, the present investigation was aimed to study the induction of DNA damage by CPF in freshwater teleost fish Channapunctatus using micronucleus assay (MN assay) and alkaline single-cell gel electrophoresis (comet assay). The value of LC(50) - 96 h of CPF was determined as 811.98 microgl(-1) for C. punctatus, in a semi-static system and on the basis of LC(50) value three acute concentrations viz., 203, 406 and 609 microgl(-1) were determined. The fishes were exposed to the different concentrations of CPF for 96 h and samplings were done at regular intervals for assessment of the MN frequencies and DNA damage. In general, significant effects (P<0.01) from both concentrations and time of exposure were observed in exposed fishes. It was found that the micronucleus induction was highest on 96 h at all concentrations in the peripheral blood. Similar trend was observed for the DNA damage measured in terms of the percentage of tail DNA in the lymphocyte and gill cells. This study explored the combined use of micronucleus assay and comet assay for in vivo laboratory studies using fresh water fish for screening the genotoxic potential of xenobiotics. 相似文献
13.
Surface distortions in the form of wrinkles are often observed in sheet metals during stamping and other forming operations. Because of the trend in recent years towards thinner, higher-strength sheet metals, wrinkling is increasingly becoming a more common and troublesome mode of failure in sheet metal forming. The prediction and prevention of wrinkling during a sheet forming process are important issues for the design of part geometry and processing parameters. This paper treats the phenomenon of flange wrinkling as a bifurcated solution of the equations governing the deep drawing problem when the flat position of the flange becomes unstable. Hill’s bifurcation criterion is used to predict the onset of flange wrinkling in circular and square cup drawing. In particular, the maximum cup height that can be drawn without the onset of flange wrinkling is predicted for the given set of process parameters. A parametric study of the maximum cup height is also carried out with respect to various geometric, material and process parameters. Finite element formulation, based on the updated Lagrangian approach, is employed for the analysis. The incremental logarithmic strain measure, which allows the use of a large incremental deformation, is used. The stresses are updated in a material frame. The material is assumed to be elastic–plastic, strain hardening, yielding according to an anisotropic yield criterion of Barlat et al. (2005) [23] (named as Yld2004-18p). Isotropic power law hardening is assumed. Inertia forces are neglected due to small accelerations. Modified Newton–Raphson iterative technique is used to solve the nonlinear incremental equations. 相似文献
14.
Shweta Paroha Arvind K. Singh Chandel Ravindra Dhar Dubey 《Environmental Chemistry Letters》2018,16(1):71-77
Coenzyme Q10 is an antioxidant present in the human body. Coenzyme Q10 has an essential role in various biochemical reactions. The deficiency of coenzyme Q10 in the body leads to disorders including neurological degeneration, ageing and cancer. Clinical trials have tested coenzyme Q10 as a drug or a dietary supplement. However, the major pharmaceutical issue of coenzyme Q10 delivery is its high molecular weight and poor water solubility. This limitation leads to its poor oral bioavailability. Several methods have been designed to overcome the poor water solubility of coenzyme Q10, such as size reduction and ionization. This article presents nanotechnology-based drug delivery systems for coenzyme Q10 with special emphasis on pharmacokinetic perspectives and clinical relevance. Systems include nanoparticles, solid dispersions, liposomes, nanoemulsions, self-emulsifying drug delivery systems, nanostructured lipid carriers, cyclodextrins and nanocapsules. 相似文献
15.
Goudar Naganagouda Vanjeri Vinayak N. Hiremani Vishram D. Gasti Tilak Khanapure Sheela Masti Saraswati P. Chougale Ravindra B. 《Journal of Polymers and the Environment》2022,30(6):2419-2434
Journal of Polymers and the Environment - The novel polyelectrolyte complexes (PEC) were prepared by mixing different Wt% of Tragacanth gum (TG) to Chitosan (CS) and systematic evaluation of... 相似文献
16.
Hiremani Vishram D. Goudar Naganagouda Gasti Tilak Khanapure Sheela Vanjeri Vinayak N. Sataraddi Sarala D’souza Oshin Jacintha Vootla Shyam Kumar Masti Saraswati P. Malabadi Ravindra B. Chougale Ravindra B. 《Journal of Polymers and the Environment》2022,30(4):1314-1329
Journal of Polymers and the Environment - This study explains the development of eco-friendly polyvinyl alcohol (PVA)/oxidized maize starch (OMS)/Betel leaves extract (BLE) blend films by employing... 相似文献
17.
Chemical and biological extraction of metals present in E waste: A hybrid technology 总被引:2,自引:0,他引:2
Management of metal pollution associated with E-waste is widespread across the globe. Currently used techniques for the extraction of metals from E-waste by using either chemical or biological leaching have their own limitations. Chemical leaching is much rapid and efficient but has its own environmental consequences, even the future prospects of associated nanoremediation are also uncertain. Biological leaching on the other hand is comparatively a cost effective technique but at the same moment it is time consuming and the complete recovery of the metal, alone by biological leaching is not possible in most of the cases. The current review addresses the individual issues related to chemical and biological extraction techniques and proposes a hybrid-methodology which incorporates both, along with safer chemicals and compatible microbes for better and efficient extraction of metals from the E-waste. 相似文献
18.
Gasti Tilak Hiremani Vishram D. Kesti Sheetal Suresh Vanjeri Vinayak N. Goudar Naganagouda Masti Saraswati P. Thimmappa Shivasharana Chandrabanda Chougale Ravindra B. 《Journal of Polymers and the Environment》2021,29(10):3347-3363
Journal of Polymers and the Environment - In this study, we prepared Poly (vinyl alcohol) (PVA)/Guar gum (GG) based nanocomposite films with a different weight ratio of silver nanoparticles (AgNPs)... 相似文献
19.
Khaiwal Ravindra Suman Mor 《Environmental science and pollution research international》2018,25(32):31929-31934
India accounts for around 50% of the world’s open defecation, and under a World Bank initiative, a rural district was selected to be the first open defecation-free (ODF) district in Punjab. Considering this, the current study aims to evaluate the application and impact of a smartphone-based instant messaging app (IMA) on the process of making Fatehgarh Sahib an ODF district. The District Administration involved the Water Supply and Sanitation Department, Non-government Organizations, and volunteers to promote the process of a community-led total sanitation. Proper training was provided to the volunteers to spread awareness about the triggering events, health impacts of open defecation, and monetary benefits of building new individual household latrine (IHHL). IMA was used as an aid to speed up monitoring and for the evaluation of a sanitation program. All the volunteers were connected to an IMA. This helped in providing a transparent and evidence-based field report on triggering events, follow-up activities, validation of existing IHHL, and monitoring of construction of new IHHL. IMA is a cost-effective tool as it is already being used by the volunteers and requires no additional cost (on the user or on the project) but requires a training on ethical uses of mobile and data safety. 相似文献
20.
Kaliannan Durairaj Palaninaicker Senthilkumar Palanivel Velmurugan Mahadeo Mahadik A. Ravindra Bulakhe N. Jae-Jin Shim 《Environmental science and pollution research international》2019,26(6):5305-5314
Environmental Science and Pollution Research - Saccharum officinarum leaves (SL) assisted nano-silica (NS) were synthesized and used as adsorbent to remove Pb2+ and Zn2+ from aqueous solutions. The... 相似文献