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91.
Satyanarayan Patel K. S. Srikanth Arif Ali Baig Moghal Niyaz Ahamad Madhar 《Integrated ferroelectrics》2016,176(1):95-108
This article presents the effect of processing parameters on the ferroelectric hysteresis behavior of Ba0.85Sr0.15Zr0.1Ti0.9O3 (BSZT) ceramics. The ferroelectric hysteresis scaling relations for coercive field (Ec) and remnant polarization (Pr) as a function of temperature have been proposed. The power law temperature exponents based on scaling were systematically established for all the hysteresis parameters. The temperature dependent scaling of Ec and Pr at sintering temperature of 1400, 1425, 1450 and 1475°C yields EcαT0.43, EcαT0.84, EcαT0.50, EcαT0.37 and PrαT?1.73, PrαT?1.55, PrαT?1.73, PrαT?1.69 respectively. Additionally, the scaling relations for the samples sintered at 1450°C at different time intervals of 3, 4, 5 and 6 hrs were also established. Finally, to understand the domain dynamics, back switching polarization (Pbc) as a function of temperature (T) was also estimated by Arrhenius law and the average activation energy was evaluated. 相似文献
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BACKGROUND: Increasing global protein consumption has led to the demand for new sources of food protein, particularly plant sources. Many inexpensive but protein‐rich bean cultivars have not been well evaluated and are thus underutilised. In this study the physicochemical and functional properties of seeds of ten seem cultivars were assessed. RESULTS: In agreement with their sizes, seeds of Airet had the highest 1000‐seed weight and volume, while those of Bari had the lowest. In terms of proximate composition (g kg?1), protein content ranged from 240.08 (Ashina) to 292.63 (Puti), fat content from 31.47 (Goalgadda) to 38.40 (Puti), ash content from 32.80 (Puli) to 45.53 (Goalgadda) and fibre content from 21.90 (Tatulia) to 28.90 (Noldog). Hydration (g kg?1) and swelling (mL L?1) capacities ranged from 1688.60 and 1850.43 (Goalgadda) to 1999.40 and 2208.66 (Rupbhan) respectively. Similarly, cooking time (min) varied from 114 (Rupbhan) to 179 (Goalgadda). Lowest gelation concentration was in the range 80–100 g kg?1. Water and fat absorption capacities (g kg?1) ranged from 941.00 and 644.44 (Ashina) to 1043.33 and 749.26 (Puti) respectively. Foaming capacity and stability (mL L?1) ranged from 443 (Puli) to 635 (Puti) and from 314 (Ashina) to 643 (Rupbhan) respectively. CONCLUSION: Seeds of seem cultivars appear to be a promising food in terms of their protein content and functionality. Copyright © 2009 Society of Chemical Industry 相似文献
95.
Dharmendra Pal Shahanshah Haider Abdi Ghanshyam Tripathi Virendra Kumar Maurya Kapil Sachan Sagir Ahamad Khan 《Journal of Materials Science: Materials in Electronics》2013,24(5):1562-1568
Sintered ceramic samples of Na2Ti3O7 with 50 % (1.0 Molar Percentage of Li2CO3 i. e. 50 % Lithium) with different doping molar percentages MnO2 (0.0 < X<0.1) have been prepared through solid state reaction route. The microstructure, EPR, dielectric properties and ac conductivity of (NaLi)Ti3O7 with Mn [0.0 ≤ X≤0.1] have been investigated. The X-ray diffraction patterns of pure and doped layered ceramics suggest the crystals are orthorhombic in phase. The room temperature electron paramagnetic resonance spectra reveal that that for lower percentage of doping manganese ions occupies Ti 4+ site with oxidation state Mn3+, while higher percentage of manganese ions doping leads to oxidation state Mn2+ in interlayer mixed (Na Li) site. In both cases the charge compensation mechanism should operate to maintain the overall charge neutrality of the lattice. For all pure and doped layered ceramics, ferroelectric transition having high transition temperature has been identifying at 648 K. Manganese ion doping decreases dielectric loss and increases dielectric constant due to inhibition of domain wall motion. It is apparent that ionic conduction becomes difficult due to presence of more lithium ions with sodium ions in interlayer space which shrinking the wide space of interlayer channels. 相似文献
96.
Golam Saleh Ahmed Salem So Kazama Daisuke Komori Shamsuddin Shahid Nepal C. Dey 《Water Resources Management》2017,31(6):1947-1959
Adaptation to increasing irrigation cost due to declination of groundwater level is a major challenge in groundwater dependent irrigated region. The objective of this study is to estimate the optimum abstraction of groundwater for irrigation for sustainable management of groundwater resources in Northwest Bangladesh. A data-driven model using a support vector machine (SVM) has been developed to estimate the optimum abstraction of groundwater for irrigation and a multiple-linear regression (MLR)-based model has been developed to estimate the reduction of the irrigation cost due to the elevation of the groundwater level. The application of the SVM model revealed that the groundwater level in the area can be kept within the suction lift of a shallow tube-well by reducing pre-monsoon groundwater-dependent irrigated agriculture by 40%. Adaptive measures, such as reducing the overuse of water for irrigation and rescheduling harvesting, can keep the minimum level of groundwater within the reach of shallow tube-wells by reducing only 10% of groundwater-based irrigated agriculture. The elevation of the groundwater level through those adaptive measures can reduce the irrigation cost by 2.07 × 103 Bangladesh Taka (BDT) per hectare in Northwest Bangladesh, where the crop production cost is increasing due to the decline of the groundwater level. It is expected that the study would help in policy planning for the sustainable management of groundwater resources in the region. 相似文献
97.
Golam Kabir Haruki Suda Ana Maria Cruz Felipe Munoz Giraldo Solomon Tesfamariam 《Structure and Infrastructure Engineering》2019,15(6):725-739
Natural hazard triggering technological disasters (Natech) events pose risks to industrial facilities and process plants. As these plants handle hazardous materials, they can endanger nearby residential areas and have financial consequences. Thus, proper Natech risk assessment is required for effective prevention, mitigation and emergency response planning at industrial plants and nearby residential areas. The parameters used to quantify Natech risk assessment are subject to uncertainties and their interactions are non-linear. In this study, a Bayesian belief network-based Natech risk assessment model is developed to assess the earthquake-related Natech risk considering different levels of uncertainties. The cause and effect relationships between different parameters are constructed based on published body of knowledge and expert knowledge. The capabilities of the proposed model are demonstrated for the earthquake-related Natech risk assessment of Kobe City, Higashinada Ward, Japan because of the Great Hanshin earthquake in 1995. The proposed model is also capable of performing both predictive analysis and diagnostic analysis. 相似文献
98.
Extracting quantitative information about absolute concentrations from high-resolution (1)H NMR spectra of complex mixtures such as brain extracts remains challenging. Partial overlap of resonances complicates integration, whereas simple line fitting algorithms cannot accommodate the spectral complexity of coupled spin systems. Here, it is shown that high-resolution (1)H NMR spectra of rat brain extracts from 11 distinct brain regions can be reproducibly quantified using a basis set of 29 compounds. The basis set is simulated with the density matrix formalism using complete prior knowledge of chemical shifts and scalar couplings. A crucial aspect to obtain reproducible results was the inclusion of a line shape distortion common among all 73 resonances of the 29 compounds. All metabolites could be quantified with <10% and <3% inter- and intrasubject variation, respectively. 相似文献
99.
Moustafa Omar Ahmed Abu‐Shawiesh B. M. Golam Kibria Florence George 《Quality and Reliability Engineering International》2014,30(1):25-35
In this paper, we proposed a new bivariate control chart denoted by based on the robust estimation as an alternative to the Hotelling's T2 control chart. The location vector and the variance‐covariance matrix for the new control chart are obtained using the sample median, the median absolute deviation from the sample median, and the comedian estimator. The performance of the proposed method in detecting outliers is evaluated and compared with the Hotelling's T2 method using a Monte‐Carlo simulation study. A numerical example is considered to illustrate the application of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
100.
We studied the reaction between urea and formaldehyde with the purpose of preparing new polychelates of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) metal ions. These compounds were characterized by elemental analysis, IR spectroscopy, 1H‐NMR, electronic spectroscopy, thermogravimetric analysis (TGA), and molar conductance measurements. The percentage of metal in all of the polychelates was found to be consistent with 1:1.5 (metal/ligand) stoichiometry. The thermal behaviors of these coordination polymers were studied by TGA in a nitrogen atmosphere up to 750°C. The TGA results reveal that the complexes had higher thermal‐resistance properties compared to the common urea–formaldehyde resin. The molar conductivity and magnetic susceptibility measurements of the synthesized polychelates confirmed the geometry of the complexes. The antibacterial activity of the polychelates was also investigated with agar diffusion methods. The antibacterial activity of these polychelates was found to be reasonably good compared with standard drugs, namely, ciprofloxacin, ampicillin, and kanamycin. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 928–936, 2006 相似文献