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961.
In the present work, Zn2SnO4 nanoparticles were doped with silicon to improve their electrical and optical properties by the conventional solid‐state reaction method. The results showed that the minimum electrical resistivity of about 0.09 Ωcm was obtained for Zn2SnO4 nanoparticles with 3% Si doping. The decrease in the electrical resistivity can be attributed to the insertion of Si+4 atoms into the Zn+2 and/or Sn+4 sites and also the formation of more oxygen vacancies in the Zn2SnO4 lattice. The formation of the more oxygen vacancy defect states in Si‐doped Zn2SnO4 nanoparticles was verified by photoluminescence spectroscopy. The efficiency of a dye‐sensitized solar cell based on 3% Si‐doped Zn2SnO4 was significantly better, by about 81%, compared to that of a cell based on the undoped Zn2SnO4. The enhancement in the efficiency can be ascribed to the facilitation of electron transport throughout a photoelectrode due to increase in the charge carrier concentration which was caused by Si doping. 相似文献
962.
Decision-makers in manufacturing area frequently face machine tool selection problem under uncertainty due to competitive market changes. Special purpose machines (SPMs), a relatively new class of reconfigurable machine tools, are used to react quickly to changes. Justification of utilising these machines vs. other machine tools requires a technique to investigate the sources of uncertainties. In this work, sensitivity analysis is utilised to investigate the sources of these uncertainties and errors which may reveal new insights for evaluating a machine tool. An illustrative example is provided to show the sensitivity of parameters on the economic performance of SPMs compared to the other alternatives. The results show that this analysis provides additional information and moves the decision closer to the optimum alternative. 相似文献
963.
964.
Seyedeh Faezeh Taghizadeh Majid Azizi Javad Asili Fatemeh Sadat Madarshahi Hasan Rakhshandeh Yoshiharu Fujii 《Food Science & Nutrition》2021,9(6):2908-2914
To assist the development of new therapeutic strategies for several disorders, biologically active peptides/proteins obtained from plant sources can be considered. Current study expected to determine the biological activities of peptide fractions of Mucuna pruriens against hepatocellular carcinoma cell lines (HepG2/ADM, HepG2, SMMC-7721, and QGY-7703), as well as normal cell line to prove their selectivity. Moreover, anti-genotoxicity and antiviral activity against the hepatitis C virus (HCV) were assessed. The methods of this study were to isolate the peptides of M. pruriens and hydrolysate fractionation via fractionated pepsin-pancreatin hydrolysates by ultrafiltration/high-performance ultrafiltration cell, identify anti-hepatoma activity of peptide fractions human liver cancer and normal cells by (3-(4,5-dimethylthiazole-2-yl)-2,5-biphenyl tetrazolium bromide) (MTT) assay, determine anti-HCV, and assess anti-genotoxic effect of peptide fractions against damage that induced via alkylating agent methyl methanesulphonate in human mononuclear cells. The results showed that the fraction 5–10 kDa has been reported to exhibit significant cytotoxic activity against HepG2 and QGY-7703. It was proven that both of 5–10 and >10 kDa fractions are active against HCV. The cytotoxic concentration (CC50) of 5–10 kDa against the cell line was 703.04 ± 5.21 µg/ml. Anti-genotoxic activities of the peptide fractions were evaluated as mean values for the analyzed comet images. In this regard, the highest activity of protecting DNA damages was observed by the peptide fraction of 5–10 kDa. This study revealed the potential ability of peptide fractions of M. pruriens for the treatment of liver cancer, HCV, and high activities of protecting DNA damages. 相似文献
965.
Majid Mohammadzadeh Enayat Berizi Seyed Shahram Shekarforoush 《Food Science & Nutrition》2021,9(4):2308-2315
In this study, the production of emulsion-type sausage by replacement of 20% to 40% KCl plus 1% or 2% yeast extract instead of NaCl was studied. The physical, chemical, microbiological, and sensory properties of the samples were analyzed up to 28 days of storage. The sample sausages were approved by the panelists. The physical, chemical, and microbiological properties of emulsion-type sausages were not considerably influenced by these changes. The 40% replaced salt by KCl showed a similar property rather than the regular sausages. The aroma and taste of the sausages improved by using yeast extract. In addition, the adverse flavors resulted from adding KCl were excluded by adding the yeast extract. As a result, production of healthy emulsion-type sausages (having 40% lower NaCl) with acceptable sensory qualities was introduced. 相似文献
966.
In this study, an innovative in situ green strategy was applied to prepare bacterial cellulose/silver nanocomposites using green tea as a substrate for the fermentation of Acetobacter xylinum bacteria and a reducing agent for the in situ synthesis of silver nanoparticles. The samples were analyzed by different characterization tests including field emission scanning electron microscopy (FESEM), X-ray diffraction analysis (XRD), UV–vis spectroscopy, atomic absorption spectroscopy, and ATR. The results indicated the excellent antibacterial activities with 100% bacterial reduction percentage and inhibition zones of 2.6 and 2.8 cm against S. aureus and E. coli, respectively. Moreover, water absorption percentage and vertical wicking measurements supported the hydrogel properties of the prepared bio-cellulose/silver nanocomposites. Finding of this research suggested the potential of the proposed green route for preparing antibacterial BC which can be regarded as a candidate for future wound healing applications. 相似文献
967.
Majid Shabanpour Babak Mohammadhosseini Mohammad Reza Khani Jaber Khanjani Babak Shokri Amirreza Ghassami 《Polymer Engineering and Science》2021,61(5):1581-1593
In this research, the polypropylene (PP) sheets used for automotive bumper surface were treated using two methods: air atmospheric gliding arc plasma and flame modifications. Atomic force microscopy was applied to study the morphology of surfaces before and after treatment processes. While calculating the surface free energy (SFE), contact angle of the surfaces was measured, and the chemical composition of the PP surface was analyzed using X-ray photoelectron spectroscopy. Surface modifications by gliding arc plasma increased the ratio of the oxygen and nitrogen atoms on the surface by 100%, indicating that polar chemical functionalities form on the surface. The surface morphology was highly affected by gliding arc plasma treatments, which triggered an impact on roughness and etching. It was also found that the SFE was drastically increased by certain modifications. Noticeable improvement was also observed in wettability by the gliding arc plasma technique. In the next stage, polyurethane paints were coated on the treated and untreated PP surfaces. Then, we examined the flame and gliding arc plasma treatments' effect on coating properties of PP bumper, adhesion analysis, water immersion resistance, and sulfuric acid resistance. Finally, high-pressure carwash test and gloss analysis were conducted on the treated and untreated coated sheets, respectively. 相似文献
968.
Majid Salehi Sina Zamiri Hadi Samadian Jafar Ai Laleh Foroutani Arman Ai Mehdi Khanmohammadi 《应用聚合物科学杂志》2021,138(16):50225
The main aim of the current study was to develop a chitosan hydrogel containing Aloe vera gel and Ethylenediaminetetraacetic acid (EDTA) as the wound healing materials. Chitosan with the concentration of (2% w/v) was prepared in AA (0.5%, v/v) and Tetrasodium EDTA (0.01% w/w) and AV (0.5% v/v) were added to the prepared polymer solution. As prepared solution was cross-linked by β-GP with the weight ratio of 1/6 w/w (1 chitosan and 6 β-GP). The characterization of the hydrogels showed that the hydrogels have porous structures and interconnected pores with the pores size range from 41.5 ± 14 to 48.3 ± 11 μm. The swelling and weight loss measurements of the hydrogels showed that the hydrogels could swell up to 240% of their initial weight during 8 h and loss 79.7 ± 3.5% of the initial weight during 14 days. The antibacterial studies depicted that the prepared Cs/tEDTA/AV hydrogel inhibited the growth of Staphylococcus aureus (the minimum inhibition concentration, MIC of 73 ± 4.8) and Pseudomonas aeruginosa (the MIC of 40 ± 7.9). Moreover, the prepared hydrogels were hemocompatible (Cs/tEDTA/AV: OD of 0.24 ± 0.30) and biocompatible (Cs/tEDTA/AV: OD of 0.38 ± 0.01). At the final stage, the wound healing assessments in the animal model revealed that the application of the prepared hydrogels effectively enhanced the wound healing process. In conclusion, the results confirmed the efficacy of the prepared hydrogels as the wound healing materials. 相似文献
969.
E. Pavitra G. Seeta Rama Raju Seyed Majid Ghoreishian Cheol Hwan Kwak Jin Young Park Young-Kyu Han Yun Suk Huh 《Ceramics International》2019,45(4):4781-4789
Energy conservation and environmental safety are the key requirements in the modern world. We report novel orange-emitting double perovskite Ba2LaNbO6:Eu3+ (BLN:Eu3+) nanophosphor fabricated using a citrate sol-gel method for use in general illumination and photocatalysis. After annealing at 800?℃, the particles exhibited a nanorod-like morphology with monoclinic structure. The photoluminescence emission spectra exhibited an intense 5D0→7F1 transition at 594?nm and a moderate 5D0→7F2 transition at 615?nm, demonstrating that the Eu3+ ions occupied the La3+ sites with inversion symmetry. The optimal concentration of Eu3+ ions was found to be about 5?mol% for the BLN host lattice. Energy transfer from the NbO67- octahedrons to the Eu3+ ions was clearly witnessed when the BLN:Eu3+ nanophosphors were excited with both the characteristic excitation bands of Eu3+ (7F0→5L6) and NbO67- octahedrons at 392 and 380?nm, respectively. The thermal quenching temperature of 5?mol% Eu3+ ions doped BLN nanophosphors was found to be 183?℃, indicating that these nanophosphors are very stable at high temperatures. In addition, the dye removal efficiency of the proposed BLN nanophosphors was verified using Rhodamine B (RhB) dye as a model pollutant under UV irradiation. Compared to a commercial nano-ZnO catalyst, our synthesized BLN nanophosphors showed superior RhB de-colorization efficiency. Therefore, the proposed BLN:Eu3+ nanophosphors are promising multifunctional materials for photocatalysis and general lighting applications. 相似文献
970.
Behrouz Elahi Mahdi Mirzaee Majid Darroudi Reza Kazemi Oskuee Kayvan Sadri Mohammad Sadegh Amiri 《Ceramics International》2019,45(4):4790-4797
Cerium oxide nanoparticles (CNPs) with desired particle size and spherical morphology were prepared from cerium nitrate in bio media of Salvia macrosiphon Boiss seeds extract, as a green synthesis route. Then they were characterized by XRD, UV–Vis and FTIR spectroscopies, FESEM and TGA. Band gap energy of the prepared powders was also determined which was found in the range of 2.5–3.5?eV. Determination of DLS and zeta potential were showed that CNPs had the small size and unique colloidal stability, respectively. Then the photo-catalytic activity of them was investigated by degradation of Rhodamine B (RhB) dye as a model of waste water pollutants, under UV-irradiation and optimum conditions were evaluated. Results showed that decreasing the particle size increased the rate of photo-catalytic reaction remarkably but ascending the band gap energy, in contrast. The photo-catalytic mechanism was also studied by using different scavengers. 相似文献