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91.
Negin Karami Abolfazl Kamkar Yasser Shahbazi Ali Misaghi 《Packaging Technology and Science》2020,33(11):469-484
The objectives of the current study were to examine physical–mechanical, structural, and morphological characteristics of chitosan-flaxseed mucilage films enriched with Ziziphora clinopodioides essential oil (ZEO; 0%, 0.25%, and 0.5%) and sesame oil (SO; 0% and 0.75%) and to provide useful information for the preservation of minced trout fillet's using antimicrobial films under aerobic, vacuum, and modified atmosphere conditions for 16 days. The films showed thickness, tensile strength, puncture force, puncture deformation, water vapor transmission rate, water vapor permeability, swelling index, and oxygen permeability values ranging 0.082–0.86 mm, 33.34–46.83 MPa, 25.69–53.08 N, 11.45–28.45 mm, 17.48–26.73 g/m2 h, 8.57–12.49 × 10−4 g mm/m2 h Pa, 12.45–38.43%, and 3.02–13.32 × 10−12 cm3/m2 s Pa, respectively. The following order of effect on the microbial spoilage population of treated samples was found in the applied packaging methods: modified atmosphere packaging > vacuum packaging > aerobic packaging. The final microbial population of treated samples was 0.35–4.91 log CFU/g lower than the controls after 16 days of refrigerated storage. At the end of the storage, the total volatile base nitrogen, peroxide value, and thiobarbituric acid reactive substances of untreated samples were 34.02–48.6 mg of N/100 g, 1.43–2.32 meq of peroxide/1000 g, and 3.33–4.24 mg of malondialdehyde/kg, respectively. The lowest corresponding values were recorded for the treated samples with ZEO 0.5% + SO 0.75% films by 14.26–17.73 mg of N/100 g, 0.48–0.86 meq of peroxide/1000 g, and 1.08–1.48 mg of malondialdehyde/kg, respectively. 相似文献
92.
Lc is the minimum length of carbon nanotubes (CNTs) required for efficient transfer of filler conductivity to polymer matrix in polymer CNT nanocomposites (PCNTs). In this work, Lc is correlated with the dimensions of the CNTs and the interphase thickness. Subsequently, the interfacial conductivity as well as the effective length and concentration of CNTs are expressed by CNT and interphase properties. Moreover, a simple model for the tunneling conductivity of PCNTs is developed with these effective terms. The impacts of all parameters on Lc, the interfacial conductivity, the fraction of CNTs in the networks and the conductivity of the PCNT are explained and justified. In addition, the predictions of the percolation threshold and conductivity are compared with the experimental results of several samples. The desirable values of interfacial conductivity are achieved by thin, short and super‐conductive CNTs, high waviness and a thick interphase. However, thin and long CNTs, low waviness, a thick interphase, poor tunneling resistivity due to the polymer matrix and a short tunneling distance advantageously affect the conductivity of PCNTs, because they produce large conductive networks. The predictions also show good agreement with the experimental measurements of percolation threshold and conductivity, which confirms the developed equations. © 2020 Society of Chemical Industry 相似文献
93.
Niknezhad Seyyed Vahid Morowvat Mohammad Hossein Najafpour Darzi Ghasem Iraji Aida Ghasemi Younes 《Food science and biotechnology》2018,27(6):1735-1746
Food Science and Biotechnology - Exopolysaccharide (EPS), as potential microbial base polysaccharide source, has plenty of applications due to its unique physicochemical structure. A Pantoea sp.... 相似文献
94.
This study investigates the unsteady electro-osmotic flow (EOF) of a fractional second-grade fluid through a vertical microchannel with convection heat transfer. The fractional Cattaneo heat flux model will be used to modify the heat equation. The solutions for the velocity and the temperature have been derived by employing the Laplace and finite Fourier sine transforms and their numerical inverses. The results show that at the beginning of the time period, the fractional parameter postpones the movement of the fluid. Furthermore, the results show that at the high values of retardation time (non-Newtonian case), the required time for the velocity and the flow rate to reach the steady state increases. Moreover, the heat relaxation time reduces the heat transfer until a critical time, and then the effect reverses. 相似文献
95.
Golouje Yavar Nourollahi Abtahi Seyyed Mahdi 《Journal of Mechanical Science and Technology》2021,35(1):31-43
Journal of Mechanical Science and Technology - In this paper, the control of chaotic vibrations in vehicle suspension system is studied via a fuzzy fast terminal sliding mode method. Therefore, the... 相似文献
96.
Wireless Personal Communications - This study investigates a novel concept of using slot and Coplanar Waveguide fed antenna to obtain multiband operation. The compact antenna includes a star... 相似文献
97.
Fatemi Seyyed Amirasad Ahmadi Morteza Rostami Jamal 《Bulletin of Engineering Geology and the Environment》2018,77(2):501-513
Bulletin of Engineering Geology and the Environment - In recent years, anumber of models and formulas have been proposed to estimate the penetration rate of hard rock tunnel boring machines (TBMs).... 相似文献
98.
99.
A novel two-step knowledge-based exploratory framework is proposed in this paper for studying quality of Italian mobile telecommunication services (MTSs). Particularly, the Delphi technique is initially considered to finalize an overall quality structure of MTSs features, indicators and drivers, herein described on the basis of a comprehensive review of the fundamental references for the field, and also to select the key elements with reference to the Italian context. At the second step, selected key elements are prioritized via the analytic hierarchical process method according to viewpoints of the fundamental stakeholders for the sector. Furthermore, possible uncertainty and ambiguity of involved experts at this step of the study are addressed via a linguistic comparison scale represented by fuzzy numbers. Results of the first step revealed that the quality structure of Italian MTSs includes 15 key indicators with reference to four key MTSs quality features and seven key drivers. On the other hand, results of the second step pointed out that tangible aspects represents the fundamental key MTSs quality feature, whereas network population coverage, price of data services, and internet network performance represent the crucial key indicators. In addition, technological resources and technological innovation as well as informational resources constitute the most important key quality drivers of Italian MTSs. Obtained results may be of interest for MTSs managers and decision makers as well researchers of the field offering important suggestions as to how to evaluate and improve quality of MTSs. 相似文献
100.
Seyyed Arash Azimi Siavash Ahmadi Zahra Ahmadian Javad Mohajeri Mohammad Reza Aref 《International Journal of Communication Systems》2018,31(1)
HIGHT is a lightweight block cipher introduced in CHES 2006 by Hong et al as a block cipher suitable for low‐resource applications. In this paper, we propose improved impossible differential and biclique attacks on HIGHT block cipher both exploiting the permutation‐based property of the cipher's key schedule algorithm as well as its low diffusion. For impossible differential attack, we found a new 17‐round impossible differential characteristic that enables us to propose a new 27‐round impossible differential attack. The total time complexity of the attack is 2120.4 where an amount of 259.3 chosen plaintext‐ciphertext pairs and 2107.4 memory are required. We also instantiate a new biclique cryptanalysis of HIGHT, which is based on the new idea of splitting each of the forward and backward keys into 2 parts where the computations associated to each one are performed independently. The time complexity and data complexity of this attack are 2125.7 and 242, respectively. To the best of our knowledge, this is the fastest biclique attack on full‐round HIGHT. 相似文献