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101.
Farzad Saberi Fatemeh Kouhsari Samaneh Abbasi Cristina M. Rosell Mehdi Amini 《International Journal of Food Science & Technology》2021,56(12):6559-6571
The aim of the study was to evaluate the physical and microstructural characteristics of crackers baked in four different industrial baking ovens (indirect radiation-cyclotherm, indirect convection, hybrid and industrial tunnel-ITO). Indirect convection and cyclotherm ovens provide the highest (5685.43 ± 51 W m−2) and the lowest (4860 ± 38.87 W m−2) amount of heat flux, respectively. Despite the amount of heat flux, indirect convection led to crackers with the highest moisture (7.86% vs. 4.82% in clyclotherm) and specific volume, but the lowest hardness. Cyclotherm resulted in crackers with lower specific volume, surface area, porosity, smooth and regular surface. Conversely, the hybrid and ITO ovens showed closer heat flux, leading to crackers with similar moisture content, texture parameters, specific volume, browning and inner porosity. Overall results show the potential of baking using different ovens for modifying the quality parameters of the crackers. 相似文献
102.
The current investigation describes a computational technique to solve one- and two-dimensional Fredholm integral equations of the second kind. The method estimates the solution using the discrete collocation method by combining locally supported radial basis functions (RBFs) constructed on a small set of nodes instead of all points over the analysed domain. In this work, we employ the Gauss–Legendre integration rule on the influence domains of shape functions to approximate the local integrals appearing in the method. In comparison with the globally supported RBFs for solving integral equations, the proposed method is stable and uses much less computer memory. The scheme does not require any cell structures, so it is meshless. We also obtain the error analysis of the proposed method and demonstrate that the convergence rate of the approach is high. Illustrative examples clearly show the reliability and efficiency of the new method. 相似文献
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Fatemeh Mohammadi 《Fullerenes, Nanotubes and Carbon Nanostructures》2018,26(4):218-225
Phosphorous-doped carbon nanotubes (PCNTs) was prepared via two-step methodology employing chemical vapor deposition, by using available starting materials and catalyst. First, CNTs was produced from acetylene gas at 750 ºC and then, PCNTs have been prepared with total yield of 44% by recooking of the prepared CNT with Ph3P at 600 ºC. The product was characterized with FESEM, TEM and EDS analyses, which confirmed its nanotube shape and the presence of phosphorous atom. The high thermal stability of the product was obtained from TGA analysis, showing only 16.5% weight loss up to 890 ºC. The Raman spectrum of the product showed the ID/IG ration equal to 0.84. Moreover, the catalytic potency of the product has been examined in ORR electrochemical reaction using CV and LSV diagrams. The results confirmed appropriate catalytic activity and high stability of the product for this process. 相似文献
106.
Aida Karimi Seyed Hesam Mirfarsi Soosan Rowshanzamir Fatemeh Beyraghi Daniel Lester 《国际能源研究杂志》2020,44(11):8877-8891
Weak phase separation and vulnerable linking groups between aromatic units are common setbacks of sulfonated aromatic proton exchange membranes (PEMs) from durability point of view. In this study, sulfonated poly(ether ether ketone) (SPEEK) membranes were exposed to Fenton's solution for a specific time, ranging from 10 to 60 minutes. Chemical structure and morphology evolution, decay in mechanical and thermal stability, and H2 permeability of SPEEK membranes were evaluated during the chemical degradation. Less-entangled polymeric chains with lower average molecular weight of degraded SPEEK samples diminished mechanical rigidity. In addition, reduction of aromatic rings in each repeat unit led to higher thermal decomposition rate. Furthermore, randomly distributed micro-defects in the SPEEK morphology and an increase in water sorption can reduce the fatigue strength of membranes in the wet-dry cycles. Eventually, hydrogen cross-over rate was gradually increased, and henceforth, accelerated destructive radical formation and degradation can be predicted. 相似文献
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108.
H2S Reactive Absorption from Off‐Gas in a Spray Column: Insights from Experiments and Modeling 下载免费PDF全文
H2S removal from an off‐gas stream was performed in a spray column by H2S reactive absorption into a NaOH solution. The individual and interactive effects of three independent operating variables on the percentage of absorbed H2S were investigated: the initial pH of the scrubbing solution, the initial scrubbing solution temperature, and the volumetric liquid‐to‐gas ratio. The optimum operating variables were determined by response surface methodology (RSM) attaining a percentage of absorbed H2S of 98.7 ± 0.2 %. Additionally, the process performance was modeled by an artificial neural network (ANN) to predict the percentage of absorbed H2S. The results showed that the experimental data agreed better with the ANN model than with the RSM results. 相似文献
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Zhale Gholampour Shamami Mir Saeed Seyed Dorraji Seyyedeh Fatemeh Hosseini Mohammad Hossein Rasoulifard Ismael Hajimiri Alireza Amani-Ghadim 《Ceramics International》2021,47(15):21334-21342
The current paper focuses on synthesizing a high-efficiency microwave absorber via incorporating the nanofillers of graphene oxide-polyaniline (GO-PANI), barium-strontium titanate (BST), and soft-hard ferrite within the polyester matrix. The nanocomposite magnets of (Ba0.5Sr0.5Fe12O19)1-x hard/(CoFe2O4)x soft (x = 0.2, 0.5, and 0.8) were prepared using sol-gel auto-combustion method. The GO-PANI and BST were successfully synthesized by in situ polymerization and improved polymerization, respectively. The phase structure, chemical structure, morphology, and microwave absorption properties of the synthesized nanocomposites were characterized by X-ray diffractometer (XRD), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscope (SEM), vector network analyzer (VNA) techniques, respectively. The results showed that the synergistic effects of the combination of dielectric (BST), conductive (GO-PANI), and magnetic materials (hard-soft ferrites) provided the reflection loss values of less than ?20 dB (>99% absorption) in the X-band region. The minimum reflection loss of ?35 dB (>99.99% absorption) was obtained by the optimal formulation including (Ba0.5Sr0.5Fe12O19)0.2 (CoFe2O4)0.8, and the weight ratio of 1: 2 for both BST/soft-hard ferrite and hard-soft ferrite + BST/GO-PANI with the thickness of 1 mm. According to the results, the thickness factor plays a key role in improving the impedance matching. Consequently, the proposed nanocomposite can be employed as a novel kind of microwave absorbers with good impendence matching and high absorption. 相似文献