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91.
Uniform fine particles of nickel basic carbonate were synthesized by heating, aqueous solution containing 0.08 mol dm−3 nickel sulfate and 0.8 mol dm−3 urea, at 85°C for various periods of time. These particles were then coated with copper compound by heating them in aqueous dispersion, containing urea and copper nitrate, at 85°C. The coating material was found to be amorphous and was composed of Cu2(OH)2CO3. The coating mixture, when heated under similar conditions in the absence of the dispersed cores, produced greenish dispersion of the precipitated particles [coating precursor solids]. The later were also amorphous in nature and had the same chemical composition [Cu2(OH)2CO3] as that of the coating material of the coated particles. Air-dried core, coated, and coating precursor materials were calcined at 700°C for 1 h at the heating rate of 5°C min−1 in the air atmosphere, which converted them into NiO, NiO[core]/CuO[coating], and CuO, respectively. Scanning electron microscopic examination showed no sintering occurred in all these solids during the calcinations process and the particles retained their identities to a significant extent.  相似文献   
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Results of investigations into the effect of tensile deformation on the magnetic characteristics of powder carbon steels preliminarily rolled to different degrees of plastic deformation are reported. The effect of plastic deformation on the strength characteristics of powder steels having different porosities and carbon contents is discussed. The possibility of estimating the mechanical properties of powder steels by magnetic methods is considered.  相似文献   
94.
The synthesized polyaniline (PANI) is doped with different concentrations of Samarium(III) chloride (SmCl3). The electrical conductivity of doped PANI samples has been measured in the temperature range (300–400K). It has been found that dc conductivity increases with the increase of dopant concentration. Different parameters, based on the conductivity, such as pre‐exponential factor (σ0) and activation energy (ΔE) have also been calculated. These parameters exhibit information about the nature and suitability of the dopant. Doped samples are characterized by FTIR and photoluminescence studies, which show the interaction of dopant with PANI. Two sharp peaks of different intensities from PL spectra at 388 and 604nm have appeared in doped PANI, which might be due to the effect of SmCl3. It has been observed that SmCl3 (dopant) shows noticeable changes in the electrical and spectroscopic properties of doped PANI. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
95.
Journal of Mechanical Science and Technology - Natural fiber composites have great potential for reducing the product cost, lowering weight and enhancing renewability. Functionality and performance...  相似文献   
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Multi-objective optimization models with an index were developed based on farmers’ preferences, local requirements, supplies available at the head of the canal, system losses, crop demand about different growth stages, and field soil moisture balance. The models were applied using linear programming. The Model 1 determines the cropping pattern by maximizing net economic benefits using a monthly basis lumped volume available at the head of the canal and is set to the minimum and maximum area constraints along with the constraint of minimum main crop area. The areas for different crops given by the first model form input for the Model 2. The other inputs of Model 2 included periodic supply available at the head of the primary canal (7-day period in this study), root growth depth, demand, and soil moisture constants. The Model 2 optimizes the sum of relative yields of all the crops and provide the irrigation levels of various crops for specified periods. Finally, the distributed area and irrigation levels determined by Model 2 are used in conjunction with the losses to decide flow rates of off takes. The complete program was implemented in the West branch irrigated area of Mirpurkhas subdivision. The results showed that the resources were allocated to off-takes in a competitive and conflict-free manner.

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Wireless Personal Communications - The paper presents a prediction of non-linear exogenous signal by optimized intelligent auto-regressive neural network model (ARNN). A signal comprises of two...  相似文献   
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Development of cost efficient, flexible and light weight paper electrodes for high-tech applications is high in demand in era of modern disposable technology. In this study α-MnO2 nanorods were fabricated through hydrothermal method by varying growth time and further combined with lignocelluloses fibers extracted from self growing plant, Monochoria Vaginalis. Crystal structure, morphology and thermal properties of MnO2 nanorods were characterized by X. Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Thermogravimetric Analysis (TGA), respectively. FESEM image analysis revealed the highest aspect ratio of 48.016 for 4?h treated MnO2 sample and high purity level was confirmed by XRD. MnO2 sample with high aspect ratio, relatively pure and larger yield was selected for incorporation of lignocelluloses fibers to fabricate flexible, light-weight and environmentally safe LC/MnO2 composite paper sheet. Furthermore, LC/MnO2 composite sheet was employed as working electrode in 2?M sodium sulfate electrolyte for cyclic voltammetry measurements. Presented LC/MnO2 composite sheet revealed specific capacitances 117, 59, 39, 25 and 23?F/g at scan rates of 5, 10, 20, 50 and 100?mV/s, respectively. Incorporation of LC fibers within MnO2 nanorods as binders will open the possibilities to fabricate the flexible paper electrode for application in supercapacitors and batteries due to facile synthesis, light-weight and environmentally friendly aspects.  相似文献   
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