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71.
We have investigated the problem of reflection and refraction of thermoelastic wave at a solid–liquid interface in presence of initial stress. Using the theory of generalized thermoelasticity the problem has been solved in the context of various linear theories of thermoelasticity namely Lord–Shulmon, Green–Lindsay and coupled thermoelasticity. The appropriate expressions to find the amplitude ratios for all the three cases of P-wave incidence, SV-wave incidence and thermal wave incidence have been developed. However the ratios of amplitudes of reflected and refracted waves to that of incident wave are computed numerically for earth’s crust-water interface, for incident P-wave only, considering the initial stress to be tensile as well as compressional both. The results obtained are discussed and compared in the three models of thermoelasticity. The variations of the amplitude ratios with initial stress in G–L model have also been shown. 相似文献
72.
Pradhan Susanta Kumar Ambade Balram 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(2):459-466
A modified LED fluorimetry determination of uranium in Nb/Ta minerals has been developed. The mineral is brought into solution by fusion with mixed phosphate flux (NaH2PO4, H2O and Na2HPO4). Iron quenches uranium fluorescence when it is present above the ratio of (iron to uranium) 100. Uranium is separated in ethyl acetate by solvent extraction and then stripped back into pyrophosphate buffer (pH ~ 7) prior to its LED fluorimetry determination. This modified method has been applied for the determination of uranium in synthetic mixtures and Nb/Ta minerals including Certified Reference Materials (X1807) with high degree of accuracy and precision.
相似文献73.
Tanmay Gupta Ambikeya Pradhan Sanchita Bandyopadhyay‐Ghosh Subrata Bandhu Ghosh 《先进技术聚合物》2019,30(9):2392-2401
Lightweight and flexible biosensors that can sustain mechanical deformation and can be adhered to human skin is an interesting field of study. In the current article, a systematic study on development of thermally exfoliated graphene oxide (TEGO)–reinforced poly(vinyl alcohol) (PVA)–based conductive hydrogel nanocomposites has been reported. The free‐standing hydrogels were synthesized using controlled and repetitive freeze‐thaw cycles. The samples were then studied for their mechanical as well as electrical properties. The hydrogels were characterized for their microstructural, chemical, and rheological properties to understand the observed macroscopic properties. Additionally, a study on the behavior of hydrogels immersed in phosphate‐buffered saline (PBS) was carried out to investigate their hydrolytic stability within simulated biological environment. Overall, the nanocomposite hydrogels demonstrated excellent static and dynamic mechanical performance, stability in PBS, considerable electrical conductivity, and significant electrical response to applied external stress, establishing their potential for use as flexible biosensors. 相似文献
74.
Raj Bali Anirudh Pradhan Hassan Amirhashchi 《International Journal of Theoretical Physics》2008,47(10):2594-2604
A model of a cloud formed by massive strings is studied in the context of the usual general relativity. This model is used
as a source of Bianchi type VI
0 massive with magnetic field and bulk viscosity. To get a determinate model, we assume that the expansion (θ) in the model is proportional to the shear (σ) and also the fluid obeys the barotropic equation of state. The behaviour of the models from physical and geometrical aspects
in presence and absence of magnetic field and bulk viscosity is discussed. 相似文献
75.
Jyotsnendu Giri Pallab Pradhan Vaibhav Somani Hitesh Chelawat Shreerang Chhatre Rinti Banerjee Dhirendra Bahadur 《Journal of magnetism and magnetic materials》2008
Nanomagnetic particles have great potential in the biomedical applications like MRI contrast enhancement, magnetic separation, targeting delivery and hyperthermia. In this paper, we have explored the possibility of biomedical applications of [Fe1−xBxFe2O4, B=Mn, Co] ferrite. Superparamagnetic particles of substituted ferrites [Fe1−xBxFe2O4, B=Mn, Co (x=0–1)] and their fatty acid coated water base ferrofluids have been successfully prepared by co-precipitation technique using NH4OH/TMAH (Tetramethylammonium hydroxide) as base. In vitro cytocompatibility study of different magnetic fluids was done using HeLa (human cervical carcinoma) cell lines. Co2+-substituted ferrite systems (e.g. CoFe2O4) is more toxic than Mn2+-substituted ferrite systems (e.g. MnFe2O4, Fe0.6Mn0.4Fe2O4). The later is as cytocompatible as Fe3O4. Thus, Fe1−xMnxFe2O4 could be useful in biomedical applications like MRI contrast agent and hyperthermia treatment of cancer. 相似文献
76.
D.K. Mishra D.R. Sahu S.K. Singh P.K. Mishra A.K. Pradhan B.K. Roul 《Journal of magnetism and magnetic materials》2008
This paper reports a novel and low-cost thermal plasma assisted heating method for ultrafast sintering of rare-earth-based perovskite manganites. An indigenously designed DC thermal plasma reactor has been used to sinter La0.67Ca0.33MnO3 (LCMO) colossal magnetoresistance (CMR) material. Highly dense (96% of theoretical density) crystalline bulk LCMO ceramics were prepared within 2.5 min of sintering time. Plasma-sintered LCMO bulk ceramics showed enhanced TC (272 K), which is close to TIM (275 K) as compared to the conventional sintered LCMO [J.M. De Teresa, M.R. Ibarra, J. Blasco, J. Garcia, C. Marquina, P.A. Algarabel, Z. Arnold, K. Kamenev, C. Ritter, R. von Helmolt, Phys. Rev. B 54 (1996) 1187] sample. We observe that the thermal plasma heating process offers a unique advantage for quick physical densification and hence sintering within a few minutes. 相似文献
77.
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80.
JPC – Journal of Planar Chromatography – Modern TLC - The Inula genus has been used for the cure of pulmonary, heart diseases and also acts as a rejuvenator, immunomodulator in... 相似文献