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排序方式: 共有605条查询结果,搜索用时 15 毫秒
81.
Saeedeh Zarbakhsh Hashem Kazemzadeh-Beneh Somayeh Rastegar 《Journal of Food Safety》2020,40(2):e12752
The effects of chitosan (CTS), ascorbic acid (AsA), and citric acid (CtA) on quality preservation of (Punica granatum cv. “Jahrom”) processed arils were investigated. The arils were immersed in aqueous solutions including water (control), CTS (0.5 and 1%), AsA (1 and 2%), and CtA (1 and 2%) and stored at 5–7°C for 15 days. Results showed that AsA maintained water loss; inhibited color change, phenolic, and anthocyanin degradation; increased vitamin C; and decreased total soluble solids and titratable acidity as compared to control. The efficiency was better for AsA than CtA and thus the effect of CTS on quality safety except to protect water loss was approximately ineffective. AsA also exhibited a significantly lower decay percentage, probably due to the suppressing peroxidase and polyphenol oxidase followed by improving antioxidant power and maintaining catalase activity, which displayed that AsA exerts an antibrowning effect. Moreover, the positive effects of AsA result in getting a higher score in sensory quality at the end storage. 相似文献
82.
Lingye Chen Fatemeh Hassani Nia Tobias Stauber 《International journal of molecular sciences》2021,22(24)
Investigations on ion channels in muscle tissues have mainly focused on physiological muscle function and related disorders, but emerging evidence supports a critical role of ion channels and transporters in developmental processes, such as controlling the myogenic commitment of stem cells. In this review, we provide an overview of ion channels and transporters that influence skeletal muscle myoblast differentiation, cardiac differentiation from pluripotent stem cells, as well as vascular smooth muscle cell differentiation. We highlight examples of model organisms or patients with mutations in ion channels. Furthermore, a potential underlying molecular mechanism involving hyperpolarization of the resting membrane potential and a series of calcium signaling is discussed. 相似文献
83.
Hashem Gharababaei Abolfazl Darvizeh Mansour Darvizeh 《Journal of Mechanical Science and Technology》2010,24(9):1855-1864
In this paper, experimental responses of the clamped mild steel, copper, and aluminum circular plates subjected to blast loading
are investigated. Extensive experimental results concerning variations of central deflection are presented. Approximate energy
analysis is used for the analytical modeling of the mid-point deflection thickness ratio of the circular plates. The essence
of the model is to describe the deformation profile, which depends on the distribution of impulsive load. By using the present
modeling, one can show how the midpoint deflection varies with the variations of the important parameters. The results obtained
from the present model show very good agreement with the experimental data. 相似文献
84.
Kohoutek J Bonakdar A Gelfand R Dey D Nia IH Fathipour V Memis OG Mohseni H 《Nano letters》2012,12(5):2537-2541
We report a type of infrared switchable plasmonic quantum cascade laser, in which far field light in the midwave infrared (MWIR, 6.1 μm) is modulated by a near field interaction of light in the telecommunications wavelength (1.55 μm). To achieve this all-optical switch, we used cross-polarized bowtie antennas and a centrally located germanium nanoslab. The bowtie antenna squeezes the short wavelength light into the gap region, where the germanium is placed. The perturbation of refractive index of the germanium due to the free carrier absorption produced by short wavelength light changes the optical response of the antenna and the entire laser intensity at 6.1 μm significantly. This device shows a viable method to modulate the far field of a laser through a near field interaction. 相似文献
85.
In this paper, the cross-phase modulation Kerr nonlinear effect is utilized to induce nonlinearity and a change in the coupling length by a high-intensity pump signal in the nonlinear photonic crystal directional coupler. We have analyzed and modified the nonlinear square-lattice directional couplers for the first time, to the best of our knowledge, and have improved the power consumption for inducing the nonlinear switching. We have shown that according to the slower group velocity and the increased confinement of the TM modes with lower frequency in the region with a higher dielectric constant in a square lattice, the required switching pump power of the structure is less than that of the same triangular structure. 相似文献
86.
Abstract This study deals with the topic of reflection and refraction of light from the boundary of a high-gain saturating laser amplifier. Expressions for the electric field and intensity reflection and transmission coefficients are obtained for the case of a wave in a uniform dielectric that is incident normally on a nonlinear saturating active medium. Bistability effects are predicted even for the simplest case of zero frequency detuning from the line centre of the saturating transition. 相似文献
87.
Mohamed Y. Hashem Sayeda S. Ahmed Mohsen A. El-Mohandes Mahrous A. Gharib 《Journal of Stored Products Research》2012
The susceptibility of the different life stages of the saw-toothed grain beetle Oryzaephilus surinamensis to different modified atmospheres (MAs) containing various concentrations of carbon dioxide (CO2) was studied as an alternative to methyl bromide fumigation at 30 °C and 65 ± 5% relative humidity (r.h.). The tested MAs were 55%, 65%, 75% and 85% CO2 gas in the air. Mortality (%) was recorded after exposure periods of 3, 6, 12, 24, 48, 72 and 96 h. Larvae and adults were more susceptible while eggs and pupae were more tolerant to CO2. A two-day exposure period was adequate to completely kill larvae and adults under all tested MAs. All eggs and pupae were killed after four days of exposure to the high-CO2 atmospheres (75% and 85%). 相似文献
88.
SiO2 nanoparticles of a quantum size (15 nm or less) were prepared via sol–gel method using tetraethylorthosilicate as a precursor. SiO2 nanoparticles were characterized by X‐ray diffraction (XRD) and field‐emission scanning electron microscopy (FESEM) analyses. Polyethersulfone/silica (PES/SiO2) crystal structure nanocomposite was prepared by in situ polymerization using silica nanoparticles as reinforcement filler. The polymerization reaction was done at 160°C in paraffin bath in the presence of diphenolic monomers. XRD and FESEM analyses were used to study the morphology of the synthesized nanocomposite. The purity and thermal property of the PES/SiO2 nanocomposite were studied by energy dispersion of X‐ray analysis and differential scanning calorimetry, respectively. The effect of silica particles on the hydrophilicity of PES/SiO2 nanocomposite was also investigated. It was showed that the PES/SiO2 nanocomposite had a higher swelling degree when compared with the pure PES. The synthesized PES/SiO2 powder was used to remove Cu(II) ions from its aqueous solution. The effect of experimental conditions such as pH, shaking time, and sorbent mass on adsorption capacity of PES/SiO2 nanocomposite were investigated. It was found that incorporation of a low amount of silica (2 wt%) into the polymer matrix caused the increase of the Cu(II) ions adsorption capacity of PES. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers 相似文献
89.
We introduce a new layered manufacturing machine with its associated geometric cutting force model. This machine is designed to build metal parts and is a modified type of commercial layered object manufacturing (LOM) machine. This apparatus uses tapered end mills with different angles instead of laser to cut the layer edges. The proposed machine needs higher stiffness, because cutting action would regularly create more inaccuracy. Consequently, a new force model is considered that takes into account cutting conditions, cutter geometry and combination of tool-workpiece materials. Then, by force and stress analysis cutting-force induced inaccuracy has been evaluated for different components of the machine. Finally, the effectiveness of the machine and its capability to build functional metal parts with different geometries is clearly shown. 相似文献
90.
Hashem Asgharnejad Ehsan Khorshidi Nazloo Maryam Madani Larijani Nima Hajinajaf Hamidreza Rashidi 《Comprehensive Reviews in Food Science and Food Safety》2021,20(5):4779-4815
Food processing is among the greatest water-consuming industries with a significant role in the implementation of sustainable development goals. Water-consuming industries such as food processing have become a threat to limited freshwater resources, and numerous attempts are being carried out in order to develop and apply novel approaches for water management in these industries. Studies have shown the positive impact of the new methods of process integration (e.g., water pinch, mathematical optimization, etc.) in maximizing water reuse and recycle. Applying these methods in food processing industries not only significantly supported water consumption minimization but also contributed to environmental protection by reducing wastewater generation. The methods can also increase the productivity of these industries and direct them to sustainable production. This interconnection led to a new subcategory in nexus studies known as water-food-environment nexus. The nexus assures sustainable food production with minimum freshwater consumption and minimizes the environmental destructions caused by untreated wastewater discharge. The aim of this study was to provide a thorough review of water-food-environment nexus application in food processing industries and explore the nexus from different aspects. The current study explored the process of food industries in different sectors regarding water consumption and wastewater generation, both qualitatively and quantitatively. The most recent wastewater treatment methods carried out in different food processing sectors were also reviewed. This review provided a comprehensive literature for choosing the optimum scenario of water and wastewater management in food processing industries. 相似文献