46 research outputs found
EXPLORATION OF NEW MULTIFUNCTIONAL MAGNETIC MATERIALS BASED ON A VARIETY OF HEUSLER ALLOYS AND RARE-EARTH COMPOUNDS
No full textMagnetic, magnetocaloric, magnetotransport and magnetoelastic properties of Ni-Mn-X (X = In, and Ga) Heusler alloys and La-Fe-Si based rare earth compounds have been synthesized and investigated by x-ray diffraction, magnetization, strain, and electrical resistivity measurements. The phase transitions, magnetic, magnetocaloric, magnetotransport and magnetoelastic properties strongly depend on the composition of these systems. In Ni50Mn50-xInx with x = 13.5, magnetocaloric and magnetotransport properties associated with the paramagnetic martensitic to paramagnetic austenitic transformation were studied. It was shown that magnetic entropy changes (SM) and magnetoresistance (MR) associated with this transformation are larger and the hysteresis effect is significantly lower when compared to that associated with paramagnetic-ferromagnetic transitions or ferromagnetic-antiferromagnetic/paramagnetic transitions in other systems. The Hall resistivity and the Hall angle shows unusual behavior in the vicinity of the martensitic phase transition for Ni50Mn50-xInx with x = 15.2. The observed Hall resistivity and Hall angle are 50 μ*cm and , respectively. It was observed that the presence of Ge, Al and Si atoms on the In sites strongly affects the crystal structure, and the electric and magnetic behaviors of Ni50Mn35In15. It was found that the partial substitution of In atoms by Si in Ni50Mn35In15 results in an increase in the magnetocaloric effect, exchange bias and shape memory effect. In Ni50Mn35In15-xSix, the peak values of positive SM for magnetic field changes H = 5 T were found to depend on composition and vary from 82 Jkg-1K-1 for x = 1 (at T = 275 K) to 124 Jkg-1K-1 for x = 3 (at T = 239 K). The partial substitution of Ni by Co in Ni50Mn35In15 significantly improves the magnetocaloric effect and MR in the vicinity of martensitic transition. In addition, significantly large inverse SM and MR were observed at the inverse martensitic phase transitions of the Ga-based magnetic shape memory Heusler alloys Ni50-xCoxMn32-yFeyGa18. The phase transition temperatures and magnetic properties were found to be correlated with the degree of tetragonal distortion in these samples. In LaFe11.57Si1.43Bx the crystal cell parameters and Curie temperatures were found to increase linearly with increasing B concentration up to ~ 0.1 % and 9 %, respectively. It was found that the characteristics of the magnetocaloric effect of LaFe11.57Si1.43 can be adjusted by a change in B concentration in the LaFe11.57Si1.43Bx system. A study of the influence of a small substitution of Ni, Cu, Cr, and V for Fe in LaFe11.4Si1.6 revealed that the magnetic, magnetocaloric, and magnetovolume coupling constant is related to an increase in the average Fe-Fe interatomic distances, leading to a change in the d-d exchange interaction
A Method of Transformation for Generalized Hypergeometric Function 2F2
No full textBy employing an addition theorem for the confluent hypergeometric function, Paris R.B.[3], has obtained a Kummer-type transformation for a 2F2 (x) hypergeometric function with general parameters in the form of a sum of 2F2 (-x) functions. Recently, Choi Junesang and Rathie Arjun K.[1], has obtained the same result without using the addition theorem. The aim of this paper is to derive the result of Paris R.B.[3], with change in the general parameters without using the addition theorem in the line of Choi Junesang and Rathie Arjun K.[1]. Corresponding author E.mail:- [email protected], [email protected]
Magnetic and Electrical Properties of Ni50Mn35In15−xSix Heusler Alloys
No full textWe have studied the magnetic and electrical properties of the polycrystalline ferromagnetic Ni50Mn35In15−xSix (1 ≤ x ≤ 5) Heusler alloys through magnetization, thermal expansion, and resistivity measurements. It was observed that an increase in Si concentration strongly affects the ground state of the martensitic phase and the magnetic properties of compounds. A magnetic phase diagram has been constructed for these alloys. It was found that both martensitic transition temperature (TM) and Curie temperature of austenitic phase (TC) decrease, while ferromagnetic ordering temperature of the martensitic phase increases with increasing Si concentration. The magnetoresistance (Δρ/ρ) associated with martensitic transformation was found to vary from –47% for x = 2 at T = 261 K to −26% for x = 5 at T = 230 K for a magnetic field change of 5 T
Black Space and the Environment
No full text"Black Space and the Environment" is a dynamic 3D data visualization project inspired by W.E.B DuBois's 1900 exhibit "The American Negro". Focusing on Pennsylvania, the project uses color and spatial analysis to reveal the impact of environmental conditions on the state's Black population. The visualization draws on data from the American Lung Association's State of the Air 2022 report and the U.S. Census Bureau to highlight correlations between disease rates and Black population density. This project aims to analyze the differential impacts of certain conditions on Black Americans and invites viewers to consider ways to combat these disproportionate outcomes.
The interactive visualization can be found at arjunphull123.github.io/black-space.
For inquiries regarding the contents of this dataset, please contact the Corresponding Author listed in the README.txt file. Administrative inquiries (e.g., removal requests, trouble downloading, etc.) can be directed to [email protected]
This item is part of the University of Arizona Libraries 2023 Data Visualization Challenge and was awarded third place in the undergraduate category.</p
The effect of partial substitution of in by Si on the phase transitions and respective magnetic entropy changes of Ni50Mn35In 15 Heusler alloy
No full textThe effect of the partial substitution of In by Si on the crystal structure, phase transition temperatures and respective magnetic entropy changes in Ni50Mn35In15-xSix with 1 ≤ x ≤ 5 have been determined using room temperature x-ray diffraction and magnetization measurements in the temperature interval 5-400 K and in magnetic fields up to 5 T. The results show that small amount of Si in the In position results a significant influence in the inverse magnetocaloric effect accompanied with the martensitic transitions in these compounds. The peak values of positive magnetic entropy change for magnetic field changes H = 5 T is found to depend on composition and vary from 82 J Kg-1 K-1 for x = 1 (at T = 275 K) to 124 J Kg-1 K-1 for x = 3 (at T = 239 K). It is found that the substitution of 20% In atoms by Si in Ni 50Mn35In15 results in an increase in positive magnetic entropy changes of more than 300%. This system also shows a negative entropy change at the Curie temperature, making this a candidate material for application in a refrigeration cycle that exploits both positive and negative magnetic entropy changes. © 2008 IOP Publishing Ltd
The study of prognostic significance of CA 15-3 in breast cancer
No full textBackground: Cancer Antigen 15-3 (CA 15-3) is a tumour-associated antigen used as serum marker for breast cancer surveillance in patients and for monitoring the response to treatment. Aim of this study was to prospectively evaluate CA 15-3 as a prognostic factor in early detection of breast cancer relapse, recurrence and early detection of distant metastasis as well as to analyse the statistical correlation between CA 15-3 levels and clinical-pathological parameters including tumour size, lymph node, histological type, grading, hormonal receptors.Methods: Sera of 85 women with breast carcinoma obtained pre-treatment, post-treatment and follow-up at 6 months were assayed for CA 15-3 by solid phase enzyme-linked immunosorbent assay (ELISA).Results: Author founds that the mean serum CA 15-3 levels in patients before treatment were significantly higher (50.59U/ml) compared with those of CA 15-3 after treatment (24.07U/ml) and follow-up at 6 months (21.07U/ml). Author also found that elevated pre-treatment serum levels of CA 15-3 were significantly correlated with poor prognosis of patients. In particular, among 16/85 patients (18.8%) that displayed over cut-off (>24.95U/ml) pre-treatment levels of CA 15-3, 2 patients (2.35%) developed recurrence,2 patients (2.35%) developed residual tumour, 2 patients (2.35%) developed advanced disease (metastases to distant sites) and 10 (11.76%) patients expired during and after study. Chi-square correlation analysis revealed that the presences of increased serum levels of CA 15-3 after treatment are significant risk factors for poor prognosis in patients.Conclusions: Elevated pre-treatment concentrations of CA 15-3 may be a useful prognostic factor for cancer progression in patients.</jats:p
Large Magnetic Entropy Change in Ni50Mn50−xInx Heusler Alloys
No full textThe magnetocaloric properties of polycrystalline Ni50Mn50−xInx (15 ⩽ x ⩽ 16) associated with the second order magnetic transition at the Curie temperature and the first order martensitic transition were studied using magnetization measurements. The refrigeration capacity and magnetic entropy change were found to depend on the In concentration and reach a maximum value of refrigeration capacity of 280 J/kg with a magnetic entropy change of −6.8 J/kg K at 318 K for a magnetic field change of 5 T. These values of the magnetocaloric parameters are comparable to that of the largest values reported near the second order transition of metallic magnets near room temperature
Phase Transitions and Magnetoresistance in Ni50Mn50−xInx Heusler Alloys
No full textThe phase transitions and magnetoresistance in polycrystalline ferromagnetic Ni50Mn50−xInx (15 ≤ x ≤ 16.2) Heusler alloys were studied through ac susceptibility, magnetization, thermal expansion, and resistivity measurements in the temperature interval of 5–400 K. The temperatures of the martensitic transformations were found to be strongly dependent on In concentration and on the strength of the applied external magnetic field. We observed large magnetoresistance (MR) Δρ/ρo ≈ −80% for x = 16 at T ≈ 125 K and Δρ/ρo ≈ −56% for x = 15 at T ≈ 309 K for ΔH = 5 T. In addition to large MR, the Ni50Mn50−xInx system exhibits ferromagnetic shape-memory effect and a large magnetic entropy change. Hence this system has potential to be a multifunctional applied material
Role of Tax Revenue, Non-tax Revenue, and Foreign Aid to Increase the Size of Budget in Nepal
No full textPurpose: The purpose of the present study is to find the impact of tax revenue, non-tax revenue, and foreign aid to increase the size of the budget in Nepal.
Methods: This study is based on descriptive, analytical, and exploratory research designs. The Johnsen Co-integration Test, VECM, Wald Test, and Granger Causality Test are used to find long-run relation, impact, short-run causality, and granger cause between the pairs of variables.
Results: The tax revenue, non-tax revenue, foreign aid, and budget are co-integrated, or they have a long-run association ship. The result of VECM shows that tax revenue, non-tax revenue, foreign aid is nicely fitted, and they are jointly significant to explain the size of the budget in Nepal. Short-run causality was found between the size of budget and tax revenue and size of budget and foreign aid, but there was an absence of short-run causality between budget and non-tax revenue in Nepal. The granger cause was not found between the pair of variables.
Implications: It seems to increase the tax revenue and decrease the dependency on foreign aid.
Limitations: This study was based on the secondary data of 40 years from the fiscal year 1979/80 to 2018/19. Only three variables, tax revenue, non-tax revenue, and foreign aid, are considered the effecting factor of the budget size. Hence, further study is necessary by employing other tools and variables.
Originality: The author was not affected by the study and findings of others
Author Correction: Delineation of partial melts and crustal heterogeneities within the crust beneath Kumaon Himalaya, India from Lg wave attenuation
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