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71.
72.
Lanthanum samarium oxalate (LSO) single crystals are grown in silica gels by the diffusion of a mixture of aqueous solutions
of lanthanum nitrate and samarium nitrate into the test tube having the set gel impregnated with oxalic acid. Tabular crystals
of LSO having well defined hexagonal basal planes are observed at different depths inside the gel. LSO crystals grown by this
method are colourless and transparent. Laue transmission X-ray diffraction pattern of LSO reveals well defined spots with
two-fold symmetry along the horizontal axis. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)
support that LSO loses water around 120°C, and CO and CO2 around 350–450°C. The infrared (IR) absorption spectrum of LSO establishes the presence of oxalate (C2 O4)2− ions. Energy dispersive X-ray analysis (EDAX) confirms the presence of La and Sm in the sample. X-ray photoelectron spectroscopic
(XPS) studies of LSO confirm the presence of La and Sm in their respective oxide states. An empirical structure for LSO has
been proposed on the basis of these findings. 相似文献
73.
Electrochemical recovery of silver from waste aqueous Ag(I)/Ag(II) redox mediator solution used in mediated electro oxidation process 总被引:1,自引:0,他引:1
Thasan Raju Sang Joon Chung Il Shik Moon 《Korean Journal of Chemical Engineering》2009,26(4):1053-1057
The paper presents a process for the electrochemical recovery of silver(Ag) by electro deposition on the electrode surface
from the waste solutions of Ag(I)/Ag(II) redox system in nitric acid medium used for the mediated electrochemical process.
Electrochemical recovery was carried out in an undivided cell with DSA-O2 electrodes at room temperature condition. At an optimized current density of 12 A/dm2, 99% of Ag recovery efficiency was achieved with high yield and low energy consumption. Experimental runs were made in order
to observe the performance of the Ag recovery process. The operating conditions like current density, temperature and Ag(I)
concentration of the electrolyte, the acid concentrations, agitation rate and inter-electrode distance were optimized. 相似文献
74.
The applicability and evaluation of a new self-starting, unconditionally stable, implicit methodology of computation for the dynamics of structures is described. The methodology offers different perspectives and architecture for structural dynamics compared with the tranditional (widely advocated and commonly used) time integration methods. It is based on velocity representations and architecture and uses finite elements as the principal analysis tool for structural dynamic modeling/analysis. In particular, the dynamics of beam-type flexural models are considered, and comparative results validate and support the proposed use of the self-starting methodology of computation for the dynamics of linear/nonlinear structures. The overall effectiveness and elegance strongly support its use in most existing commercial codes. 相似文献
75.
Mohamed Shakeel Pethuraj Burhanuddin bin Mohd Aboobaider Lizawati Binti Salahuddin 《Computational Intelligence》2023,39(6):930-949
Lung cancer is the most critical disease because it affects both men and women. Most of the time, lung cancer leads to death due to less health care and medical attention. In addition, lung cancer is difficult to identify in earlier stages due to the low-level symptoms and risk factors. To overcome the complexity, effective techniques must predict lung cancer earlier. To attain the problem statement, an lung cancer identification system is developed with the help of a meta-heuristic algorithm. The CT imageries obtained from the CIA database are analyzed step by step. The gathered image noise is removed by applying the mean filter, and the affected regions are segmented with the help of the Butterfly Optimization Algorithm-based K-Means Clustering (BOAKMC) algorithm. Afterward, various statistical features are derived, and the Supervised Jaya Optimized Rough Set related Feature Selection (SJORSFS) process is used to select the lung features. Finally, the lung cancer is identified using Autoencoder based Recurrent Neural Network (ARNN) classification algorithm, successfully recognizing the lung cancer features. Then the system's efficiency is evaluated using a MATLAB setup; here, 3000 are treated as training images and 2043 for testing images. The effective training enhances overall lung cancer prediction accuracy by up to 99.15%. 相似文献
76.
C. S. Murthy P. V. Raju S. Jonna K. Abdul Hakeem S. Thiruvengadachari 《International journal of remote sensing》2013,34(15):2865-2876
Spatial information on crop calendars in the command areas of irrigation systems is useful to irrigation engineers in order to achieve chronological synchronization between water delivery pattern and crop life cycle. Such synchronization is vital for efficient use of water. The capability of satellite remote sensing technology to generate spatial crop calendar information in an irrigated command area and its usefulness in the evaluation of water delivery patterns are demonstrated in this paper. The study pertains to the major crop paddy during the rabi season (December to June) of 1992-93, in the Bhadra project command area of Karnataka state, India. Analyses of multidate Normalized Difference Vegetation Index (NDVI) profiles of paddy crop generated from Indian Remote Sensing (IRS) satellite data for each distributary command reveal three distinct growth patterns in the study area with each pattern characterized by a particular crop calendar. The spatial variability in crop calendar over the total command area has thus been derived. The ground truth data obtained in crop cutting experiments (CCEs) validate the satellite derived crop calendar. Distributary wise, water delivery data have been studied in conjunction with the satellite derived crop calendar to determine whether the existing pattern of water delivery covers the required length of crop life cycle in the command area. It was found that the water supply was stopped about 30 days before harvesting in some distributaries and in some about 20-30 days before harvesting. A list of distributaries with greater lags between cessation of water supply and crop harvest was provided to irrigation system engineers to aid their plans for providing a reliable and predictable irrigation service. This is possible either through reorganization of canal operation schedule or through educating farmers about the need for adjusting their agricultural activities to match water supply patterns. 相似文献
77.
Bhari Mallanna Nagaraja Aytam Hari PadmasriBurri David Raju Kamaraju Seetha Rama Rao 《International Journal of Hydrogen Energy》2011,36(5):3417-3425
Cu-MgO is found to be an efficient catalyst for the coupling reaction of furfural (FAL) hydrogenation and cyclohexanol (CyOH) dehydrogenation. This process is not only efficient in compensating the thermodynamic equilibrium constraints in the cyclohexanol dehydrogenation and improving the yields towards cyclohexanone but also is a economical route for the synthesis of furfuryl alcohol (FFA) and cyclohexanone (Cyone) as the process do not need any external pumping of hydrogen. The effect of incorporation of various promoters viz., Co, Zn, Fe, Cr, Pd and Ni in Cu-MgO over its activity towards this coupling reaction has been studied. Incorporation of Cr in Cu-MgO catalyst is found be an advantageous in enhancing the yields of both FFA and Cyone. All other promoters though found to show higher activity for the individual reactions of FAL hydrogenation and CyOH dehydrogenation, failed to do the same in their coupling reaction. The stabilization of active species (Cu+/Cu0) by Cr which also seem to increase the synergetic interaction between Cu and MgO as observed from higher dispersion of copper (from XRD results) and easier reducibility of copper oxide (from TPR results) seem to be the factors behind its higher activity over other promoted catalysts. 相似文献
78.
Raju E. Jayaprakash P. Hegde Tejaswi Ashok Vinitha G. Kumaresan S. 《Journal of Materials Science: Materials in Electronics》2022,33(1):167-176
Journal of Materials Science: Materials in Electronics - A mixed solution of 2-aminopyridine and succinic acid, with a 1:1 molar ratio, was kept at room temperature to develop a 2-aminopridinium... 相似文献
79.
This investigation explores the features of velocity distribution, mass and heat transmissions of nanoliquid stream over a permeable cylinder accompanied by Cattaneo–Christov heat model and thermal radiation with nonlinear sort. Multiple slip conditions have been also encountered here. A magnetic force is oriented along vertically upward. The existence of thermophoresis together with Brownian motion has been assumed here. The foremost equations and associated boundary conditions have been normalized through the similarity technique. Then we solve the system numerically along with the fourth-order Runge–Kutta shooting scheme by using the software MAPLE-17 and round it with our preassigned accuracy level. The obtained outcomes are epitomized by tables and graphs. All of the impacts have been compared in suction and injection correspondingly and explained with proper reasoning. In charts, the physical consignments (such as Sherwood number, Nusselt number and skin friction) reveal the transference of mass and temperature and amount of friction by nanoparticles in the nanocomposition. For suction, the nanofluidic temperature gradually diminished due to the advanced thermal relaxation, whereas the contrary fact is exhibited in injection. The relaxation parameter of concentration provides a positive influence on mass transmission. The rates of amplification of this transportation are 1.99% and 3.87%, measured in consideration of injection and suction, respectively. Thermal radiation influenced the fluid's temperature in a positive direction. It increases Nusselt number with 41.75% in suction, and 45.21% is recorded for injection. 相似文献
80.
Sreenu Kurra Naveen Kumar Veldurthi Jitta Raju Reddy Chandiri Sudhakar Reddy Muga Vithal 《Journal of Materials Science: Materials in Electronics》2016,27(5):4194-4200
The photocatalytic activity of sol–gel synthesized double perovskite type oxides NaEuTi2O6(NETO), NaSmTi2O6 (NSTO), and NaGdTi2O6 (NGTO) powders on degradation of methylene blue (MB) dye was demonstrated for the first time under visible light as well as sunlight irradiation. The obtained samples were characterized by X-ray diffraction, UV–Visible diffuse reflectance spectroscopy and scanning electron microscopy equipped with X-ray energy-dispersion spectrometry. All the three samples have shown photocatalytic activity for degradation of MB under sunlight and visible light irradiation and their photocatalytic activity followed the order of NGTO > NETO > NSTO. The superior activity of NGTO is ascribed to the higher amount of hydroxyl radicals generated in the photocatalytic reaction. 相似文献