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排序方式: 共有947条查询结果,搜索用时 15 毫秒
21.
Determination of antioxidant potential of Acacia nilotica leaf extract in oxidative stress response system of Saccharomyces cerevisiae 下载免费PDF全文
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Filippo Bianchi Marcel Thielmann Roman Mani Dani Or Hans Jürgen Herrmann 《Granular Matter》2016,18(4):75
The mechanics of granular media at low liquid saturation levels remain poorly understood. Macroscopic mechanical properties are affected by microscale forces and processes, such as capillary forces, inter-particle friction, liquid flows, and particle movements. An improved understanding of these microscale mechanisms is important for a range of industrial applications and natural phenomena (e.g. landslides). This study focuses on the transient evolution of the tensile stress of unsaturated granular media under extension. Experimental results suggest that the stress state of the material evolves even after cessation of sample extension. Moreover, we observe that the packing density strongly affects the efficiency of different processes that result in tensile stress relaxation. By comparing the observed relaxation time scales with published data, we conclude that tensile stress relaxation is governed by particle rearrangement and fluid redistribution. An increased packing density inhibits particle rearrangement and only leaves fluid redistribution as the major process that governs tensile stress relaxation. 相似文献
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Mani Swaminathan Joost-Pieter Katoen Ernst-Rüdiger Olderog 《Formal Aspects of Computing》2012,24(4-6):477-496
This paper adopts the communication closed layer (CCL) concept of Elrad and Francez to the formal reasoning of randomized distributed algorithms. We do so by enriching probabilistic automata (PA) with a layered composition operator, an intermediate between parallel and sequential composition. Layered composition is used to establish probabilistic counterparts of the CCL laws that exploit independence and/or precedence conditions between the constituent PA. The probabilistic CCL laws enable partial order (po-) equivalence when layered composition is replaced by sequential composition. Such po-equivalence induces a purely syntactic partial-order state space reduction via layered separation in compositions of PA while preserving probabilistic next-free linear-time properties. The feasibility of such layered separation is demonstrated on a randomized mutual exclusion algorithm by Kushilevitz and Rabin, complementing an algebraic approach (for analyzing this algorithm) by McIver, Gonzalia, Cohen, and Morgan. 相似文献
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Akila Swaminathan Sree Rama Chaitanya Sridhara Swaraj Sinha Shunmugam Nagarajan Uma Maheswari Balaguru Jamila H Siamwala Saranya Rajendran Uttara Saran Suvro Chatterjee 《Journal of food science》2012,77(12):H273-H279
Abstract: Recent evidence has demonstrated that nitrites play an important role in the cardiovascular system. Fennel (Foneiculum vulgare) seeds are often used as mouth fresheners after a meal in both the Indian sub‐continent and around the world. The present study aims to quantify the nitrite and nitrates in fennel seeds as well as elucidating the effect of fennel derived‐nitrites on vascular functions. Results from our study show that fennel seeds contain significantly higher amount of nitrites when compared to other commonly used post‐meal seeds. Furthermore our study confirmed the functional effects of fennel derived‐nitrites using in vitro and ex vivo models that describe the promotion of angiogenesis, cell migration, and vasorelaxation. We also showed that chewing fennel seeds enhanced nitrite content of saliva. Thus our study indicates the potential role of fennel derived‐nitrites on the vascular system. Practical Application: This study is focused on determining the effect of fennel‐derived nitrites on angiogenesis (the formation of new blood vessels from pre‐existing ones), cell migration, and vasorelaxation (dilation of blood vessels) thereby preserving cardiovascular health. 相似文献
26.
Evaluation of Optimal River Training Work Using GA Based Linked Simulation-Optimization Approach 总被引:1,自引:1,他引:0
Hriday Mani Kalita Arup Kumar Sarma Rajib Kumar Bhattacharjya 《Water Resources Management》2014,28(8):2077-2092
Use of structural measures for controlling a river to minimize its devastating effect and to utilize it for the benefit of mankind is a common practice all over the world. Because of high investment, such measures require prior investigation through model study. As lab based physical model study is very expensive and time consuming, mathematical modeling is generally used for investigating different alternatives of river training works. In this study, a new approach is proposed for deciding appropriate river training measure in a particular reach of a river or channel. In this methodology, an optimization model is linked with the hydrodynamic model for obtaining cost effective combination of groynes which will maintain a user defined flow speed in a pre-decided portion of a river reach. The optimization model is developed using binary coded Genetic Algorithm (GA) and the flow simulation model uses the Beam and Warming scheme for solving the two dimensional (2D) hydrodynamic equations of unsteady flow. The performance of the model is tested by applying the methodology in a rectangular channel for attaining different target speed values at a pre-defined portion of the channel and logical results have been obtained for all the tested scenarios. 相似文献
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J. Janaki T. Geetha Kumary Awadhesh Mani E. P. Amaladass N. Radhikesh Raveendran P. Magudapathy S. Kalavathi T. N. Sairam T. R. Ravindran 《Journal of Superconductivity and Novel Magnetism》2014,27(11):2639-2643
The occurrence of superconductivity in iron telluride thin films has been observed upon ageing. The superconducting transition is found to be very robust under an application of magnetic fields up to 10 T. Infrared and Raman spectroscopic characterization of the aged films reveal the formation of Fe1+δTeO x upon ageing. As an alternative method of introducing oxygen in FeTe thin film, oxygen ion irradiation has also been carried out It is found that the irradiated film becomes increasingly disordered and ultimately transforms to an amorphous phase upon increasing the irradiation dose. Investigation of electrical resistivity and optical reflectivity of the irradiated FeTe films indicates an interesting possibility of an ion irradiationinduced phase change memory material in analogy to the phase change characteristics of laserirradiated FeTe films. 相似文献
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Kumaravel Sakthivel Thiripuranthagan Sivakumar Erusappan Elangovan Durai Mani 《Journal of Porous Materials》2022,29(4):1083-1095
Journal of Porous Materials - Among the various biomass-derived platform chemicals, levulinic acid (LA) has been identified as one of the top-10 important molecules by Department of Energy, United... 相似文献
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K. Swaminathan C. Mallika O. M. Sreedharan 《Journal of the American Ceramic Society》1987,70(7):168-C
The emf of the galvanic cell Pt|UMoO6 UMoO5 |ZrO2 -Y2 O3 |O2 (air, Po2 =0.21 atm)|Pt, measured from 776 to 1127 K, was determined to be E = 751.7−0.4909 ±4.3 mV. Using the standard Gibbs energy of formation, f ΔG°, for UMoO6 reported in the literature from transpiration studies, the f ΔG° for UMoO5 is calculated to be f ΔG°〈UMoO5 〉=−1816.9+0.3748T±6.0 U-mol−1 The magnitudes of the standard entropies of formation, f ΔS°, for UMoO6 and UMoO5 were evaluated from those values reported for the binary oxides which constitute the ternary compounds. 相似文献