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991.
Behnam Mohammadi Seyed Mohammad Mirkazemi Yaser Vahidshad Akram Dorani 《International Journal of Applied Ceramic Technology》2023,20(1):272-280
In this study, biopolymer chitosan is presented as a template for synthesizing and shaping the mesoporous γ-Al2O3 macrospheres. This porous γ-Al2O3 granule has a high surface area (310 m2/g), high pore volume (.6148 cm3/g), and pore diameter between 2 and 10 nm. The full factorial design based on a mathematical model was implemented to study the acid concentration, chitosan amount, ammonia concentration, and aging time affecting the responses (Brunauer–Emmett–Teller surface area and pore volume). Predicted responses were found to be in satisfactory agreement with experimental values (R2 = .9580 and .9109, respectively). The adequacy of the model was examined by analyzing the residual distribution plots and Pareto graph. X-ray diffraction, scanning electron microscopy (SEM), thermogravimetric analysis, and N2 adsorption/desorption techniques are employed to characterize the structure of the prepared γ-alumina sample. 相似文献
992.
Mohammad Khajeh Mehrizi Mostafa Jokar Tayebah Sadeghyan Mohammad Erfan Azizi Mohammad Reza Rahmani 《Coloration Technology》2023,139(4):385-394
The alginate thickener is the thickener frequently used for reactive printing of textile. The thickener responds with reactive pigments and thus does not lead to the fabric composition becoming stiffer. In this study, we prepared oxidised natural guar gum with hydrogen peroxide, sodium hypochlorite and sodium hydroxide. All other polysaccharides comprise reactive hydroxyl units with a stronger reactivity that must be replaced if they are to be used in reactive printing. Guar derivatives were synthesised and verified using Fourier-transform infrared (FTIR) spectroscopy. Natural thickeners, synthetic guar gum derivatives, have been employed in textile printing technique. In comparison to other synthetic thickeners, modified environmental guar gum polymer has been shown to be an ecologically friendly and low-cost thickener. Cotton fabric printed with modified guar thickening with hydrogen peroxide has even stronger colour strength than fabric printed with sodium alginate thickener, which is highly favourable. Penetration properties, colour value, colour strength, colour fastness to washing, light and rubbing was compared with alginate thickener (readily available on the market). Guar gum thickeners showed enhanced features versus sodium alginate for reactive printing. Partially replaced guar gum is an appropriate option due to the colour and physical properties. 相似文献
993.
Omid Velayatipour Leila Nikzad Mohammad Farvizi 《International Journal of Applied Ceramic Technology》2023,20(3):1667-1680
In this study, NiTi–x wt.% B4C (x = 0, 2, and 4) composites were consolidated with spark plasma sintering method, and the effects of boron carbide reinforcement addition on the microstructure and wear behavior of samples were investigated. Identification of the constituent phases of samples by the X-ray diffraction method plus Rietveld analysis revealed that the stability of the martensite phase increased in the composite samples because of mismatch stresses between the NiTi matrix phase and the reinforcing particles, which increases the density of the dislocations and facilitates the diffusion process that subsequently leads to the formation of stable intermetallics. The results of hardness test indicated that the hardness value increased from 3.67 GPa for pure NiTi to 10.99 GPa for NiTi–4 wt.% B4C. Results of wear test revealed that boron carbide reinforced composite specimens had higher wear resistance, whereas wear rate of NiTi sample was 3.6 × 10−3 mm3/N m, and it reached to .21 × 10−3 mm3/N m for NiTi–4 wt.% B4C. Investigation of microstructure by scanning electron microscopy images and EDS analysis revealed that the wear mechanism in NiTi samples was abrasive and the addition of B4C to NiTi changed the wear mechanisms from abrasive to a combination of oxidation, adhesive, and delamination mechanisms. 相似文献
994.
995.
Muhammad H. Alu'datt Taha Rababah Mohammad N. Alhamad Ghaid J. Al-Rabadi Carole C. Tranchant Ali Almajwal 《Critical reviews in food science and nutrition》2018,58(18):3209-3218
ABSTRACTPhenolic phytochemicals have become of interest due to their therapeutic potential, particularly with regards to their anti-cancer, anti-inflammatory, hypolipidemic, and hypoglycemic properties. An evolving area of research involving phenolics in foods and their products pertains to the functional, biological, and nutritional consequences resulting from the binding between certain phenolic compounds and the macronutrient and micronutrient constituents of foods. The goal of this review is to provide a summary of studies investigating endogenous phenolic interactions with major components in food systems, including carbohydrates, proteins, lipids, minerals and vitamins, with a focus on the phenolic compounds and nutrients in oil-bearing plants. Another major objective is to provide a comprehensive overview of the chemical nature of phenolic interactions with food constituents that could affect the quality, nutritional and functional properties of foods. Such information can assist in the discovery and optimization of specific phenolic complexes in plant-based foods that could be utilized towards various applications in the food, nutraceutical and pharmaceutical industries. 相似文献
996.
Mohammad Zakaria Mashud Ahmed Mozammel Hoque Abu Shaid 《Journal of Natural Fibers》2020,17(5):676-687
ABSTRACTA relatively better performance of jute fiber and yarn reinforced concrete composites can open up a wide access to application of natural resources in concrete strengthening. In order to achieve this goal, an experimental investigation on the flexural, compressive and tensile strengths of Jute Fiber Reinforced Concrete Composites (JFRCC) and Jute Yarn Reinforced Concrete Composites (JYRCC) has been conducted. To draw a specific conclusion, the mix ratios of 1:1.5:3 and 1:2:4 (by volume) of concrete have been maintained with incorporation of jute fiber and yarn in concrete mortar having different cut lengths with distinct volumetric ratios. Finally, a comparison of the JFRCC and JYRCC strength increments with respect to the plain concrete has been investigated. A significant increment of compressive, flexural and tensile strength was observed only for a short cut length having a low volumetric ratio, where JYRCC increment value was always found progressive. A far more regular arrangement and adequate mixture of JYRCC was also visualized compare to JFRCC in concrete mortar. All the principal increment values were found only in case of JYRCC with a mix ratio of 1:1.5:3. So, it can be concluded that the presence of jute yarn and more cement content can strengthen the concrete to a great extent. 相似文献
997.
Mahmoud Atashbar Mohammad Hossein Kahaei 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(1):97-99
The l1‐SVD is an efficient method for spatial sparsity based direction of arrival (DOA) estimation of narrowband signals. We propose a coherent strategy for extension of the l1‐SVD method to wideband signals. In this method, focusing matrices are used for transferring different frequency bins data to the reference bin, and then the transformed data are combined. Finally the l1‐SVD is applied for the combined data. The proposed method outperforms the non‐coherent strategy with a lower computational burden. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
998.
Mohammad Hossein Keshavarz Farhad Seif Hossein Soury 《Propellants, Explosives, Pyrotechnics》2014,39(2):284-288
The brisance parameter can be used to show the shattering power of an energetic compound and the speed to reach its peak pressure. It determines the effectiveness with which an explosive can fragment a shell. Nowadays, the sand test or sand crushing test is the preferred method for brisance measurements but there is no reliable method for the prediction of the brisance parameter. In this paper, a method for the prediction of the brisance through sand test for pure and mixed energetic materials as well as aluminized explosives is reported. It is based on the molecular structure of the desired compound and once the conclusion is established any experimental data is redundant. The calculated brisance relative to 2,4,6‐trinitrotoluene (=100) shows good agreement with the measured values. 相似文献
999.
Mohammad Hossein Keshavarz Hamid Reza Pouretedal Ali Reza Ghaedsharafi Seyed Ehsan Taghizadeh 《Propellants, Explosives, Pyrotechnics》2014,39(6):815-818
A reliable simple method for prediction of the standard Gibbs energy of formation (ΔfGθ) of energetic compounds containing nitroaromatic, acyclic, and cyclic nitramine, nitrate ester, and nitroaliphatic compounds is introduced herein. The method is based on the contribution of elemental composition (ΔfGelemθ) and the correcting function for the presence of additive and non‐additive molecular fragments (ΔfGcorrθ). In presence of some molecular moieties, ΔfGcorrθ may increase or decrease the value of ΔfGelemθ, depending on the intermolecular interactions. The experimental root‐mean‐square error (RMSE) of the novel correlation (22.7 kJ mol−1) is quite good. For some energetic compounds, where the computed values of two complex models of the quantitative structure‐property relationship (QSPR) theory were available, the experimental RMSE developed by the new method is smaller than the values obtained by QSPR method. 相似文献
1000.
Yadollah Bayat Mohammad Mahdi Ahari‐Mostafavi Narges Hasani 《Propellants, Explosives, Pyrotechnics》2014,39(5):649-652
An efficient and mild procedure for the one‐pot preparation of CL‐20 from TADB in the presence of the Brønsted acidic ionic liquid 1‐methylimidazolium hydrogen sulfate [Hmim][HSO4] as catalyst was developed. The ionic liquid was stable during the reaction process and could also be reused several times with steady activity. In order to optimize the process parameters to obtain higher yield and purity, a study was carried out with variation of the ionic liquids and some parameters like temperature, mole ratio of [Hmim][HSO4] and nitric acid. This procedure may be a practical alternative to the existing procedures to meet the nees of academics as well as industry. 相似文献