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71.
In this paper we present two semi-empirical methods for determination of Shafranov shift in IR-T1 tokamak. In the first method, solution of the Grad–Shafranov equation present, and one relation for Shafranov shift obtained, also in second method according to magnetic fields distribution around the plasma, second relation for the Shafranov shift obtained. Based on the two methods, four magnetic pickup coils were designed, constructed, and installed on the outer surface of the IR-T1 tokamak chamber and then Shafranov shift determined from them. Results of the two methods are in good agreement with each other.  相似文献   
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OBJECTIVE: The present study was designed to generate population-based data on the prevalence and causes of hearing loss in rural Pakistani children. A community screening programme was utilized to identify and evaluate the hearing impaired. METHODS: The study was performed in conjunction with the Ministry of Population Welfare in Sialkot District, Punjab Province. School-aged children between the ages of 5 and 15 years were screened and examined for hearing impairment according to World Health Organization (WHO) protocols. Case-control analysis of audiometric, physical examination, and risk factors for hearing loss were performed, followed by chi-square analyses. RESULTS: A total of 607 children comprised the study population, with an overall point prevalence of hearing impairment of 7.9%. Fifty percent of all hearing loss was conductive in nature, amenable to either medical or surgical therapy. The risk factors most associated with conductive hearing loss were otorrhea and multiple ear infections greater than 5. In cases of severe hearing loss, 70% were the result of consanguinous marriages. Almost no cases of hearing loss were attributable to measles, mumps, rubella, and the TORCH infections. CONCLUSION: This study has generated some badly needed population-based data on the magnitude of the problem of hearing loss in rural Pakistan. It is hoped that the results of this work will stress the importance of hearing health in Pakistan and to encourage other professionals to pursue similar projects.  相似文献   
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Due to the industrial applications of nasno materials, the growth of Copper oxide (CuO) nanowires (NWs) at the same and opposite directions of the electric and gravitational fields was investigated to study the effects of fields on the NWs properties. The experiments were designed to grow NWs using thermal oxidation method at 450 °C for 50 h. NWs growth was evaluated to study two distinct cases; first, substrates exposed to the gravitational field and second those treated with electric field (EF) in-lined with gravitation field (GF). It was observed that the electric field developed a diameter homogeneity while compressing the NWs and decreasing the diameters. Furthermore, the GF influenced only the length of the NWs, while the EF had an impact on both length and diameter of the NWs. The direction of fields played an important role in NWs morphology and intensity of XRD pattern and optical properties. It was also observed that field direction greatly influenced the NWs length and diameter.  相似文献   
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The effect of different extraction methods i.e. extraction with alkali (AEDF), enzyme (EEDF) and enzyme plus shear emulsifying hydrolysis (SEDF) on structure, physiochemical as well as the functional characteristics of dietary fiber (DF) from defatted walnut flour were studied. AEDF process showed significantly higher (P < 0.05) amount of water retention capacity (WRC; 5.39 g/g), water swelling capacity (WSC; 3.16 g/mL), and particle size; while, shown lower value of oil adsorption capacity (OAC; 29 g/g) amongst all. Compared to AEDF, no major differences were observed in network except the matrix in EEDF and SEDF was more porous and honey comb like. DF extracted through AEDF, EEDF and SEDF showed good viscosity and emulsifying activity however, less stability indices. The results from this study suggest that AEDF and EEDF and SEDF had specific effects on the structure-functional properties of DF from defatted walnut flour, which has great potential in food applications.  相似文献   
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Measurements of poloidal beta β p and internal inductance l i are essential in tokamak plasma research. Much more plasma parameters such as the plasma current density profile, magnetohydrodynamics instability, and plasma energy confinement time are determined by using these parameters. Discrete poloidal magnetic probes along with the diamagnetic loop can be utilized in measurement of the plasma poloidal beta β p and internal inductance l i . In this paper, theoretical and experimental results in determining β p and l i are presented and discussed.  相似文献   
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Measurement of plasma internal inductance is important in tokamak plasma experiments (plasma internal inductance relates to the plasma current profile). In this paper we present an experimental investigation of effects of Resonant Helical Field (RHF) on the plasma internal inductance in IR-T1 tokamak. For this purpose, four magnetic probes and also a diamagnetic loop with its compensation coil were constructed and installed on outer surface of the IR-T1 tokamak, and Shafranov parameter, poloidal Beta, and then the internal inductance determined. In order to investigate the effects of RHF on internal inductance, we measured it in presence and also in absence of different modes of the RHF (L = 2, L = 3, L = 2&3). Experimental results show that L = 3 mode can flat the plasma current and increase the plasma internal inductance.  相似文献   
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