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51.
Do Y Soung Anagha Patade Dania A Khalil Edralin A Lucas Latha Devareddy Kathryn A Greaves Bahram H Arjmandi 《Nutrition journal》2006,5(1):12-6
Background
The health benefits of soy isoflavones have been widely investigated; however, there are some concerns as to whether soy isoflavones, similar to ipriflavone, a synthetic isoflavone, cause lymphocytopenia in postmenopausal women. Hence, the purpose of this study was to investigate the extent to which 12-month supplementation of 25 g soy protein containing 60 mg isoflavones alters lymphocyte counts or other hematological parameters in postmenopausal women who were not on hormone replacement therapy. 相似文献52.
A new kinetic gelation model that incorporates the kinetics of non-linear free radical copolymerization is presented. Copolymerization of bi- and tetrafunctional monomer mixtures is simulated to characterize kinetic effects on polymerization statistics and microstructures. An algorithm for random next step selection in a self-avoiding random walk and efficient mechanisms of component's mobility are introduced to improve the universality of the predictions by removing commonly occurring simulation deficiencies due to early trapping of radicals. The model has the capability to predict the onset of the sol-gel transition, and the effect of chemical composition on the transition point. It is shown that a better understanding of microstructure evolution during polymerization and chemical gelation is attained. Lastly, one important benefit of the simulation method is the ability to simulate very highly packed random chains or microgels within a polymer network. 相似文献
53.
This paper reports on an attempt to investigate the stress intensity factors of equal and unequal oblique parallel edge cracks subjected to tension. The effects of the variation of the length of the cracks, angle of inclination, and crack spacings on the stress intensity factors (opening and sliding modes) were studied. Experimental observations show that, for crack spacings equal or larger than the length of the equal oblique parallel edge cracks, the size of the caustics for the cracks in the loaded specimen approach that of a single oblique edge crack with the same angle of inclination.In the case of unequal oblique parallel edge cracks, a crack closure phenomenon and its occurrance with respect to the length of the cracks and crack spacings were investigated. It was observed that the transverse diameter of the caustic for the shorter cracks became small and negligible when the position of the shorter cracks with respect to the longer cracks became smaller than half of the crack spacings.
Résumé Le mémoire est relatif à une tentative d'étude des facteurs d'intensité de contrainte relatifs à des fissures de bord parallèles et obliques de longuers égales et inégales soumises à tension. On étudie les effets de la variation de longueurs des fissures, de l'angle de leur inclinaison, et de la distance entre les fissures sur les facteurs d'intensité de contrainte dans les modes d'ouverture et de glissement. Les observations expérimentales montrent que lorsque les fissures sont espacées d'une grandeur égale ou supérieure à la longueur des fissures de bord obliques parallèles et égales, la dimension des caustiques relatives aux fissures dans une éprouvette sous charge est proche de celle relative à une fissure de bord simple oblique possédant le même angle d'inclinaison.Dans le cas de fissures de bords parallèles obliques inégales, un phénomène de fermeture de fissure a été étudié, ainsi que son apparition en fonction de la longueur des fissures et de l'espacement entre celles-ci. Il a été observé que le diamètre transversal de la caustique relative aux fissures plus courtes devient faible et négligeable lorsque la position des fissures courtes par rapport aux fissures les plus longues devient plus petite que la moitié de l'espacement entre les fissures.相似文献
54.
This work presents a framework for future studies to better understand the appropriate time to include chemical inhibitors at different stages of asphaltene aggregation in the oil. For this purpose, molecular dynamics (MD) simulations were performed to study the aggregation of asphaltene molecules in heptane, in terms of strength, dynamics, and the occurrence time of each stage of aggregation from single molecules to a large flocculate. Results indicate that the nucleation of nanoaggregates begins prior to 10?ns, clusters start forming at 98?ns, and flocculation happens after 120?ns. It was also observed that the final flocculate had a globular shape. 相似文献
55.
Masoumeh Ghalkhani Bahram Hosseini nia Javad Beheshtian Azam Anaraki Firooz 《Journal of Materials Science: Materials in Electronics》2017,28(11):7568-7574
In this study, undoped and nano Fe doped SnO2 nanostructures were synthesized by hydrothermal method. Characterization of the synthesized nanostructures was performed by X-ray diffraction and scanning electron microscopy. For investigation of optical properties, photo luminescence and UV–Vis spectrum were taken. The electrochemical response of the carbon paste electrode modified with synthesized nanostructures toward levodopa (L-Dopa) was studied. Cyclic voltammetry studies using prepared modified electrodes showed outstanding electrocatalytic properties towards electro-oxidation of L-Dopa and a significant reduction was observed in anodic over voltage compared to the bare electrode. Obtained results indicated the effective role of the employed dopant. Best response in terms of the current enhancement, overvoltage reduction, and reversibility improvement of the L-Dopa oxidation reaction under experimental conditions was obtained by modified electrode with Fe doped SnO2 nanoparticles. 相似文献
56.
Clean Technologies and Environmental Policy - The sustainability issues surrounding conventional agriculture motivate the need for exploring new sustainable methods of farming, critical for global... 相似文献
57.
This contribution reviews critically the existing entropy measures for probabilistic hesitant fuzzy sets (PHFSs), and demonstrates that these entropy measures fail to effectively distinguish a variety of different PHFSs in some cases. In the sequel, we develop a new axiomatic framework of entropy measures for probabilistic hesitant fuzzy elements (PHFEs) by considering two facets of uncertainty associated with PHFEs which are known as fuzziness and nonspecificity. Respect to each kind of uncertainty, a number of formulae are derived to permit flexible selection of PHFE entropy measures. Moreover, based on the proposed PHFE entropy measures, we introduce some entropy-based distance measures which are used in the portion of comparative analysis. Eventually, the proposed PHFE entropy measures and PHFE entropy-based distance measures are applied to decision making in the strategy initiatives where their reliability and effectiveness are verified. 相似文献
58.
Mohamed A. Mattar A. A. Alazba Bander Alblewi Bahram Gharabaghi Mohamed A. Yassin 《Water Resources Management》2016,30(11):3745-3767
This research investigates five reference evapotranspiration models (one combined model, one temperature-based model, and three radiation-based models) under hyper-arid environmental conditions at the operational field level. These models were evaluated and calibrated using the weekly water balance of alfalfa by EnviroSCAN to calculate crop evapotranspiration (ETc). Calibration models were evaluated and validated using wheat and potatoes, respectively, on the basis of weekly water balance. Based on the results and discussion, the FAO-56 Penman-Monteith model proved to be superior in estimating ETc with a slight underestimation of 2 %. Meanwhile, the Hargreaves-Samani (HS) model (temperature-based) underestimated ETc by 20 % and the Priestley-Taylor (PT) and Makkink (MK) models (radiation-based) had similar performances underestimating by up to 35 % of the measured ETc. The Turc (TR) model had the lowest performance compared with other models, demonstrating values underestimated by up to 60 % of the measured ETc. Local calibration based on alfalfa evapotranspiration measurements was used to rectify these underestimations. The surprisingly good performance of the calibrated simple HS model, with a new coefficient 0.0029, demonstrated its favorable potential to improve irrigation scheduling. The MK and PT models were in third and fourth rank, respectively, reflecting minor differences between one another. The new coefficients obtained for the MK and PT models were 1.99 and 0.963, respectively. One important observation was that the calibrated TR model performed poorly, with an increase in its coefficient from 0.013 to 0.034 to account for hyper-arid environmental conditions; moreover, it required additional seasonal calibration to adequately improve its performance. 相似文献
59.
Mohammad Masoumi Bahram Sami Kashkooli Mohammad Javad Monem Hossein Montaseri 《Water Resources Management》2016,30(14):5051-5063
In the context of water as an economic good, from the use of water, one can derive a value, which can be affected by the reliability of supply. On-demand irrigation systems provide valuable water to skilled farmers who have the capacity to maximize economic value of water. In this study, simultaneous optimization of on-demand irrigation network layout and pipe sizes is considered taking into account both investment and annual energy costs. The optimization problem is formulated as a problem of searching for the upstream head value, which minimizes the total cost (investment and energy costs) of the system. The investment and annual energy costs are obtained in two separate phases. Max–Min ant system (MMAS) algorithm is used to obtain the minimum cost design considering layout and pipe diameters of the network simultaneously. Clement methodology is used to determine flow rates of pipelines at the peak period of irrigation requirements. The applicability of the proposed method is showed by re-designing a real world example from literature. 相似文献
60.
Many water resources optimization problems involve conflicting objectives which the main goal is to find a set of optimal solutions on, or near to, Pareto front. In this study a multi-objective water allocation model was developed for optimization of conjunctive use of surface water and groundwater resources to achieve sustainable supply of agricultural water. Here, the water resource allocation model is based on simulation-optimization (SO) modeling approach. Two surrogate models, namely an Artificial Neural Network model for groundwater level simulation and a Genetic Programming model for TDS concentration prediction were coupled with NSGA-II. The objective functions involved: 1) minimizing water shortage relative to the water demand, 2) minimizing the drawdown of groundwater level, and 3) minimizing the groundwater quality changes. According to the MSE and R2 criteria, the results showed that the surrogate models for prediction of groundwater level and TDS concentration performed favorably in comparison to the measured values at the number of observation wells. In Najaf Abad plain case study, the average drawdown was limited to 0.18 m and the average TDS concentration also decreased from 1257 mg/lit to 1229 mg/lit under optimal conditions. 相似文献