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排序方式: 共有398条查询结果,搜索用时 15 毫秒
51.
Meccanica - In the present study, the two-phase gas–liquid convective heat transfer is numerically studied inside uniformly heated wavy micro-tubes in the Taylor flow regime. Both Newtonian... 相似文献
52.
Rock Porous Structure Characterization: A Critical Assessment of Various State-of-the-Art Techniques
Razavifar Mehdi Mukhametdinova Aliya Nikooee Ehsan Burukhin Alexander Rezaei Amin Cheremisin Alexey Riazi Masoud 《Transport in Porous Media》2021,136(2):431-456
Transport in Porous Media - The porous structure of geomaterials is of utmost importance for various industrial and natural processes. In this study, various conventional porous structure... 相似文献
53.
Fazli Ghiyasabadi Sakineh Habibagahi Ghassem Nikooee Ehsan 《Transport in Porous Media》2021,137(3):489-518
Transport in Porous Media - The establishment of the representative elementary volume (REV) in studies of porous media is crucial for linking microscopic structure and pore-scale fluid... 相似文献
54.
Saeid Zanganeh Amir Kajbafvala Navid Zanganeh Matin Sadat Mohajerani Aidin Lak M. R. Bayati H. R. Zargar S. K. Sadrnezhaad 《Applied Physics A: Materials Science & Processing》2010,99(1):317-321
A flower-like boehmite nanostructure was prepared through a template-free chemical route by the self-assembly process of nanosize
petals 800–1000 nm long, 200–250 nm wide, 20–50 nm thick and having an average crystallite size of about 2.21 nm. X-ray diffraction
analysis (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), DTA/TGA analyses and Brunauer–Emmet–Teller
(BET-N2) analyses were used in order to characterize the product obtained. XRD results exhibited that the obtained nanostructures
composed of pure orthorhombic AlOOH phase. The effects of Cl− ions and TEA on the growth of boehmite three-dimensional nanoarchitectures in the presence of
NO3-\mathrm{NO}_{3}^{-}
ions were investigated. BET analyses of as-prepared material demonstrate that this nanostructure material has a high specific
surface area, as high as 123 m2 g−1. 相似文献
55.
56.
Dzhaparidze and Spreij (Stoch Process Appl, 54:165–174, 1994) showed that the quadratic variation of a semimartingale can be approximated using a randomized periodogram. We show that the same approximation is valid for a special class of continuous stochastic processes. This class contains both semimartingales and non-semimartingales. The motivation comes partially from the recent work by Bender et al. (Finance Stoch, 12:441–468, 2008), where it is shown that the quadratic variation of the log-returns determines the hedging strategy. 相似文献
57.
Ehsan Momtahan 《代数通讯》2013,41(4):1484-1488
In this note, we show that a compact Hausdorff space X is dense-separable if and only if every family of ideals of C(X) with zero intersection has a countable subfamily with zero intersection. As a consequence of this characterization we observe that every compact dense-separable space whith Soc(C(X)) = 0 has a countable dense and co-dense subset. 相似文献
58.
Thaksen Jadhav Yuan Fang William Patterson Cheng‐Hao Liu Ehsan Hamzehpoor Dmitrii F. Perepichka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):13891-13895
Designing structural order in electronically active organic solids remains a great challenge in the field of materials chemistry. Now, 2D poly(arylene vinylene)s prepared as highly crystalline covalent organic frameworks (COFs) by base‐catalyzed aldol condensation of trimethyltriazine with aromatic dialdehydes are reported. The synthesized polymers are highly emissive (quantum yield of up to 50 %), as commonly observed in their 1D analogues poly(phenylene vinylene)s. The inherent well‐defined porosity (surface area ca. 1000 m2 g?1, pore diameter ca. 11 Å for the terephthaldehyde derived COF‐1) and 2D structure of these COFs also present a new set of properties and are likely responsible for the emission color, which is sensitive to the environment. COF‐1 is highly hydrophilic and reveals a dramatic macroscopic structural reorganization that has not been previously observed in framework materials. 相似文献
59.
Mahian Omid Ebrahimnia-Bajestan Ehsan Poncet Sébastien 《Journal of Thermal Analysis and Calorimetry》2019,135(1):23-28
Journal of Thermal Analysis and Calorimetry - 相似文献
60.
Ehsan Zeimaran Sara Pourshahrestani Nahrizul Adib Kadri Daniel Kong Seyed Farid Seyed Shirazi Sangeetha Vasudevaraj Naveen S. S. Murugan T. S. Kumaravel Babak Salamatinia 《Macromolecular bioscience》2019,19(10)
Stretchable self‐healing urethane‐based biomaterials have always been crucial for biomedical applications; however, the strength is the main constraint of utilization of these healable materials. Here, a series of novel, healable, elastomeric, supramolecular polyester urethane nanocomposites of poly(1,8‐octanediol citrate) and hexamethylene diisocyanate reinforced with cellulose nanocrystals (CNCs) are introduced. Nanocomposites with various amounts of CNCs from 10 to 50 wt% are prepared using solvent casting technique followed by the evaluation of their microstructural features, mechanical properties, healability, and biocompatibility. The synthesized nanocomposites indicate significantly higher tensile modulus (approximately 36–500‐fold) in comparison to the supramolecular polymer alone. Upon exposure to heat, the materials can reheal, but nevertheless when the amount of CNC is greater than 10 wt%, the self‐healing ability of nanocomposites is deteriorated. These materials are capable of rebonding ruptured parts and fully restoring their mechanical properties. In vitro cytotoxicity test of the nanocomposites using human dermal fibroblasts confirms their good cytocompatibility. The optimized structure, self‐healing attributes, and noncytotoxicity make these nanocomposites highly promising for tissue engineering and other biomedical applications. 相似文献