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991.
A complex finite strip method was used to study the buckling of functionally graded plates (FGPs) under thermal and mechanical (longitudinal, transverse, and shear in-plane) loading. The mechanical characteristics of FGPs were assumed to vary through the thickness, according to power law distribution. The nonlinear temperature distribution in the direction of the plate thickness was assumed according to thermal conduction steady state conditions. In complex finite strip method, the polynomial Hermitian functions were assumed in the transverse direction and the complex exponential functions were used in the longitudinal direction to evaluate the standard and geometric stiffness matrices that have the ability of calculating the critical shear stress in contrast to trigonometric shape functions. The solution was obtained by the minimization of the total potential energy and solving the corresponding eigenvalue problem. In addition, numerical results for FGPs with different boundary conditions were presented and compared with those available in the literature and the interaction curves of mechanical and thermal buckling capacity of FGPs were obtained. 相似文献
992.
Photodynamic therapy (PDT) is an effective treatment method for various types of invasive tumors. The efficiency of PDT treatment depends, to a great extent, on optimal dosimetry of light, the photosensitizer used, and on tissue oxygenation. Fluorescence spectroscopy can be employed for measurement of drug concentration in target tissue and can provide a basis for in vivo evaluation of treatment efficiency. We have developed an integrated system that can be used to determine photosensitizer concentration in vivo based on fluorescence measurements. In our study, we performed fluorescence measurements on colon tumors of Balb/c mice in which CT26 cells were injected subcutaneously in the right flank. 5-Aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) was used as the photosensitizer. ALA was administered intraperitoneally at a dose of 200 mg/kg and PpIX fluorescence profiles were followed up to 34 h after ALA administration. Maximum fluorescence intensity was found 8 h after ALA administration. Also, we determined the relationship between PpIX concentration in colon tumor tissue of Balb/c mice and its fluorescence intensity at the peak of the spectrum (635 nm). This was used to determine the PpIX content in the target tissue as a function of time after ALA administration. 相似文献
993.
Mohammad Goharkhah Shahin Amiri Hossein Shokouhmand 《Journal of Mechanical Science and Technology》2009,23(12):3393-3398
The non-Fourier heat conduction problem in a finite slab is studied analytically. Dependence of thermal conductivity on space
has been considered. The Laplace transform method is used to remove the time-dependent terms in the governing equation and
the boundary conditions. The hyperbolic heat conduction (HHC) equation has been solved by employing trial solution method
and collocation optimization criterion. Results show that the space-dependent thermal conductivity strongly affects the temperature
distribution. A temperature peak on the insulated wall of the slab has been observed due to linear variation of thermal conductivity.
It has been shown that the magnitude of the temperature peak increases with increasing the dimensionless relaxation time.
To validate the approach, the results have been compared with the analytical solution obtained for a special case which shows
a good agreement. 相似文献
994.
Javad Safaei-Ghomi Abdolrasoul H. Ebrahimabadi Zahra Djafari-Bidgoli Hossein Batooli 《Food chemistry》2009
Chemical composition of the essential oil, antioxidant activity (DPPH and β-carotene/linoleic acid assays), and total phenolic content (Folin–Ciocalteu assay) of aerial parts of Thymus caramanicus were determined. The highest radical-scavenging activity (DPPH test) was shown by the polar subfraction of the methanol extract (IC50 = 43.0 μg/ml) which was also higher than that of butylated hydroxytoluene (BHT, IC50 = 19.7 μg/ml). However, it was the nonpolar subfraction of the methanol extract that showed the highest inhibition (84.4%), as assessed by the β-carotene/linoleic acid assay, which was only slightly lower than that shown by BHT (93.3%). The antioxidant activities of the essential oil main component (carvacrol) were also evaluated for comparison. Total phenolic content of the polar subfraction, as gallic acid equivalents, was 124.3 μg/mg. Essential oil extracted from the aerial parts by hydrodistillation was analysed by GC and GC/MS. Fifteen constituents, representing 99.3% of the oil, were identified, of which the major ones, carvacrol (85.9%), thymol (3.3%), p-cymene (3.2%), γ-terpinene (1.8%) and borneol (1.3%), accounted for 95.6% of the oil. 相似文献
995.
Mehdizadeh Tooraj Tajik Hossein Jafarie Sima Kaboudari Ata 《Food science and biotechnology》2019,28(5):1499-1506
Food Science and Biotechnology - The present study aimed at extending shelf life of rainbow trout fillet. Fish and seafoods are the most valuable nutrients, however, high levels of moisture, free... 相似文献
996.
997.
Hossein Shokouhmand Amirmohammad Sattari Seyed Erfan Hosseini‐Doost Ali Maghooli 《亚洲传热研究》2018,47(2):404-419
Analysis of porous fins for their higher heat transfer in comparison with solid fins with identical volumes has attracted significant attention. In this paper, a two‐dimensional thermal analysis of a porous fin having variable thermal conductivity coefficient is performed using finite difference method. Heat transfer through porous media is simulated using passage velocity from Darcy's model. The thermal conductivity of the solid phase is considered as a linear function of temperature. It is found that the temperature profile of the fin is completely two‐dimensional even for high Rayleigh and Darcy numbers (Ra = 103~104, Da = 0.01), because the temperature changes significantly along the transverse axis especially for lower Rayleigh and Darcy numbers. Also, the effects of important nondimensional parameters such as Rayleigh and Darcy numbers, porosity, Nusselt, thermal conductivity, and aspect ratio on the temperature profile are investigated. The results demonstrate that the temperature distribution is strongly dependent on the Rayleigh and Darcy numbers. 相似文献
998.
Seyed Hossein Hosseini Nazhad Ghazani 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(5):579-585
Hydrate formation and water accumulation during transmission process can be prevented by effective dehydration of gas streams. This study investigates the application of support vector machine to estimate natural gas dew point temperature using contactor temperature and TEG purity as independent variables. A data set comprised of 173 data points is extracted from the literature. The proposed model is considered a great help for engineers to have precise dew point temperature predictive tool in wide ranges of concerning variables. Results obtained from the proposed model show R-squared and mean square error of 0.992 and 5.556, respectively. Accordingly, the remarkable agreement between predicted and experimental values is observed. 相似文献
999.
Effect of cinnamon essential oil and grape seed extract as functional‐natural additives in the production of cooked sausage‐impact on microbiological,physicochemical, lipid oxidation and sensory aspects,and fate of inoculated Clostridium perfringens 下载免费PDF全文
1000.
The effect of chitosan coating incorporated with ethanolic extract of propolis on the quality of refrigerated chicken fillet 下载免费PDF全文
Nematollah Jonaidi Jafari Mina Kargozari Reza Ranjbar Hossein Rostami Hassan Hamedi 《Journal of Food Processing and Preservation》2018,42(1)
Chitosan is considered as a functional packaging component for maintaining the quality and increasing the shelf life of perishable foods include meat, poultry, fish, dairy products, and all cooked leftovers. The present study was conducted to evaluate edible coating of chitosan (2%) containing ethanolic extract of propolis (1% and 2%) on microbiological (mesophilic aerobic, psychrotrophic, lactic acid bacteria, coliforms, and Staphylococcus aureus counts), chemical (TBARS, TVN and Peroxide values) and sensory (odor, color, texture, taste, and overall acceptance) properties of chicken fillet. Microbial analysis showed that coating had a significant reducing effect on growth of bacteria during 12 days at 4 °C. Besides, the increase of TBARS, Total volatile nitrogen, and peroxide value of samples coated by chitosan and ethanolic extract of propolis was less than control group. According to our results, chitosan and propolis can be used to enhance the shelf life of fillet and maintain its quality.