| 1. |
- Abdollahi, Mehdi, 1985, et al.
(författare)
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Improvement of active chitosan film properties with rosemary essential oil for food packaging
- 2012
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Ingår i: International Journal of Food Science and Technology. - : Wiley. - 1365-2621 .- 0950-5423. ; 47:4, s. 847-853
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Tidskriftsartikel (refereegranskat)abstract
- Rosemary essential oil (REO) was used to develop an active film from chitosan. The effects of REO concentration (0.5, 1.0 and 1.5% v/v) on film properties were studied by measuring the physical, mechanical and optical properties of the REO‐loaded films. Scanning electron microscopy and Fourier transform infrared (FTIR) spectroscopy were used to study microstructure and the interaction of the chitosan‐based films. The solubility and water gain of the chitosan film decreased about 25% and 85%, respectively, by REO incorporation, up to 1.5% v/v, because of the interaction between hydrophilic groups of chitosan and REO as confirmed by FTIR. It was determined that REO improved the transparency of the films from 4.97 in neat chitosan up to 7.61; moreover, it reduced the films’ light transmission in UV light more than 25%. Films containing REO showed more antibacterial activity and total phenol content. The films containing REO showed potential to be used as active film in food preservation.
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| 2. |
- Abdollahi, Mehdi, 1985, et al.
(författare)
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Influence of chitosan/clay functional bionanocomposite activated with rosemary essential oil on the shelf life of fresh silver carp
- 2014
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Ingår i: International Journal of Food Science and Technology. - : Wiley. - 1365-2621 .- 0950-5423. ; 49:3, s. 811-818
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Tidskriftsartikel (refereegranskat)abstract
- A combination of chitosan biopolymer, nanoclay and rosemary essential oil was prepared as a functional bionanocomposite (FBN). Its ability to improve the shelf life of refrigerated (4 ± 1 °C) silver carp fillets was studied. The fresh fillets were left untreated as a control or coated with chitosan, chitosan/clay bionanocomposite and chitosan/clay/rosemary essential oil (Ch/clay/REO) FBN. Then, they were evaluated for chemical, microbial and sensory properties over 16‐day storage. The samples coated with the FBN had the lowest pH and total volatile basic nitrogen. Ch/clay/REO coating efficiently retarded lipid oxidation by decreasing peroxide, free fatty acid and thiobarbituric acid production in the samples. The coating also reduced total viable and psychrotrophic count of the fillets more than 1.5 log by the end of storage.
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| 3. |
- Abdollahi, Mehdi, 1985, et al.
(författare)
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Reducing water sensitivity of alginate bio-nanocomposite film using cellulose nanoparticles
- 2013
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Ingår i: International Journal of Biological Macromolecules. - : Elsevier BV. - 0141-8130 .- 1879-0003. ; 54:1, s. 166-173
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Tidskriftsartikel (refereegranskat)abstract
- A bio-based nanocomposite was developed by incorporation of cellulose nanoparticles (CN) obtained from sulfuric acid hydrolysis into alginate biopolymer using solution casting method. The effect of CN loading content (1, 3, 5 and 10 wt%) on microstructural, physical, mechanical and optical properties of the nanocomposites were characterized. The results showed that water solubility and water vapor permeability of the nanocomposites decreased by about 40% and 17%, respectively, upon increasing the CN content to 10%. In addition, the crystalline structure of the CN increased surface hydrophobicity of the alginate film by about 98%. The tensile strength value of the composite films increased from 18.03 to 22.4 MPa with increasing NC content from 0 to 5%; but, it decreased with further increase of the filler content. Nevertheless, film transparency decreased with CN incorporation, especially in high level (10%), which suggested the occurrence of partial agglomeration of the fillers at 10% that coincided with microstructural and mechanical results.
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| 4. |
- Albofetileh, Mehdi, et al.
(författare)
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Antimicrobial activity of alginate/clay nanocomposite films enriched with essential oils against three common foodborne pathogens
- 2014
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Ingår i: Food Control. - : Elsevier BV. - 0956-7135. ; 36:1, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- The overall objective of this study was to develop antimicrobial nanocomposite films to control the growth of foodborne pathogens. In the first step, the antibacterial effects of clove, coriander, caraway, marjoram, cinnamon, and cumin essential oils were studied against three important food pathogens, Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes by application of agar diffusion assay. The intensity of antimicrobial efficacy was in the following order: marjoram > clove > cinnamon > coriander > caraway > cumin. In the next study, the three most potent essential oils were subsequently incorporated into alginate/clay nanocomposite films. The antibacterial effectiveness of the prepared films against E. coli, S. aureus, and L. monocytogenes was studied during 12 days. The antibacterial activity of the essential oils was maintained when incorporated into the nanocomposite film. The nature and amount of the essential oils play an important role in the film's antimicrobial activity. In all film matrices, marjoram showed the highest antimicrobial activity. Films with 1.5% marjoram decreased the numbers of L. monocytogenes, E. coli, and S. aureus populations with respect to the control up to 6.33, 4.52, and 5.80 log, respectively.
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| 5. |
- Albofetileh, Mehdi, et al.
(författare)
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Effect of montmorillonite clay and biopolymer concentration on the physical and mechanical properties of alginate nanocomposite films
- 2013
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Ingår i: Journal of Food Engineering. - : Elsevier BV. - 0260-8774. ; 117:1, s. 26-33
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Tidskriftsartikel (refereegranskat)abstract
- Alginate-based nanocomposites at different montmorillonite clay (MMT) loadings were produced by solvent casting method. The combined effect of biopolymer and MMT content on the mechanical and physical properties of the obtained nanocomposites was investigated. The MMT weight percent relative to alginate was varied from 1% to 5% and polymer concentration was 1 and 1.5% w/v. Films containing 5% (wt/wt) of MMT show, with respect to neat alginate, reduced water permeability of about 19% and 22% and an increased water solubility of about 36% and 40%, for 1% and 1.5% alginate films, respectively. The tensile strength of neat alginate films increased significantly with increasing alginate concentration (about 36%) but slightly increased with increasing clay content up to 3%. The values of elongation decreased with increasing the both of clay content and polymer concentration. Results on X-ray diffraction (XRD) and transmission electron microscopy (TEM) revealed well developed exfoliated nanocomposite films especially at low level of nanoclay addition.
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| 6. |
- Albofetileh, Mehdi, et al.
(författare)
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Effect of Nanoclay and Cross‐Linking Degree on the Properties of Alginate‐Based Nanocomposite Film
- 2014
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Ingår i: Journal of Food Processing and Preservation. - : Hindawi Limited. - 0145-8892 .- 1745-4549. ; 38:4, s. 1628-1631
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Tidskriftsartikel (refereegranskat)abstract
- Montmorillonite nanoclay (MMT) and CaCl2‐reinforced alginate‐based nanocomposite film was prepared by solvent casting method. The combined effect of nanoclay addition and internal cross‐linking degree on the mechanical and physical properties of the obtained nanocomposites was evaluated. The MMT concentration was 3% and CaCl2 content in the matrix was varied from 0.01 to 0.03 ([w/w] % dry matrix). Results showed that the water vapor permeability and water solubility of the nanocomposite films significantly (P < 0.05) decreased about 30% and 39%, respectively, with the addition of MMT and CaCl2. Incorporation of both nanofiller and cross‐linking agent also improved the mechanical performance of the nanocomposites (increase in tensile strength up to 36%) compared to the neat alginate film. Nevertheless, hydrophilicity of the nanocomposite films increased with incorporating both nanoclay and CaCl2, resulted in decreased contact angle. Results on X‐ray diffraction revealed well‐developed exfoliated nanocomposite films at 3 wt % of nanoclay addition.
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| 7. |
- Bahram, Somayeh, et al.
(författare)
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Whey Protein Concentrate Edible Film Activated with Cinnamon Essential Oil
- 2014
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Ingår i: Journal of Food Processing and Preservation. - : Hindawi Limited. - 0145-8892 .- 1745-4549. ; 38:3, s. 1251-1258
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Tidskriftsartikel (refereegranskat)abstract
- An active protein‐based film was developed by incorporating cinnamon essential oil (CEO) into whey protein concentrate (WPC) at a level of 0.8 and 1.5% v/v. The effects of CEO on microstructure, physical, mechanical and antimicrobial properties of the films were evaluated. Adding CEO to the WPC matrix decreased the water vapor permeability of the films and water solubility by 38.03 and 29.4%, respectively. The films containing CEO also displayed lower affinity to water; the contact angle increased up to 89.61% in 1.5% CEO concentration. Films containing CEO showed notable antibacterial activity against both gram‐positive and gram‐negative strains, and exhibited good inhibitory effect on the studied fungi. However, CEO containing films showed a heterogeneous cracked structure which decreased their tensile strength. This combination of the results confirmed good potential to the film for application in food packaging.
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| 8. |
- Rezaei, A., et al.
(författare)
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HiWA : A hierarchical Wireless Network-on-Chip architecture
- 2014
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Ingår i: Proceedings of the 2014 International Conference on High Performance Computing and Simulation, HPCS 2014. - 9781479953127 ; , s. 499-505
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Konferensbidrag (refereegranskat)abstract
- Due to high latency and high power consumption in long hops between operational cores of NoCs, the performance of such architectures has been limited. In order to fill the gap between computing requirements and efficient communications, a new technology called Wireless Network-on-Chip (WNoC) has been emerged. Employing wireless communication links between cores, the new technology has reasonably increased the performance of NoC. However, wireless transceivers along with associated antenna impose considerable area and power overheads in WNoCs. Thus, in this paper, we introduce a hierarchical WNoC called Hierarchical Wireless-based Architecture (HiWA) to use the wireless resources optimally. In the proposed approach the network is divided into subnets where intra-subnet nodes communicate through wire links while inter-subnet communications are almost handled by single-hop wireless links. On top of that, we have also defined performance evaluation parameters. Simulation results show that the proposed architecture reduces average packet latency 16% and power consumption 14% in comparison with its conventional counterparts.
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