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11.
Jalil?ManafianEmail author Mehdi?Fazli?Aghdaei Manouchehr?Zadahmad 《Optical and Quantum Electronics》2016,48(8):410
A improvement of the expansion methods, namely, the improved \(\tan (\phi (\xi )/2)\)-expansion method for solving the sixth-order thin-film equation is proposed. As a result, many new and more general exact traveling wave solutions are obtained including singular kink-type solutions. We obtained the further solutions comparing with other methods as Flitton and King (Eur J Appl Math 15:713–754, 2004) and Taha et al. (J King Saud Univ Sci 26:75–78, 2014). Recently this method is developed for searching exact traveling wave solutions of nonlinear partial differential equations. Abundant exact traveling wave solutions including kink and rational solutions have been found. These solutions might play important role in engineering and physics fields. Also the results demonstrate that the introduced method is powerful tools for solving the nonlinear partial differential equations. 相似文献
12.
Abed Badrian Manouchehr Mamaghani Sharif Kaamyabi 《Phosphorus, sulfur, and silicon and the related elements》2016,191(10):1375-1379
Trimethylsilyl iodide (TMSI) is introduced as an efficient reagent for the one-pot and direct transformation of carbamates of unsaturated β-aminoesters into the corresponding α-methylene-β-lactams and α-arylidene-β-lactams. The mild reaction conditions, excellent yields and easy work-up procedures make it a useful alternative to previously applied procedures for the rapid synthesis of β-lactams from easily available Baylis-Hillman adducts. 相似文献
13.
Among photochromic compounds 1,3-diazabicyclo[3.1.0]hex-3-ene derivatives are currently the subject of intense research due to their photochromic behavior particularly in the crystalline state. In this work, the click syntheses of photochromic compounds containing tetrasubstituted imidazole moieties have been investigated. The structure?Cphotochromic behavior relationships of these compounds have been evaluated. 相似文献
14.
15.
Upscaled Unstructured Computational Grids for Efficient Simulation of Flow in Fractured Porous Media
Muhammad Sahimi R. Darvishi Manouchehr Haghighi M. Reza Rasaei 《Transport in Porous Media》2010,83(1):195-218
Discrete fracture modeling (DFM) is currently the most promising approach for modeling of naturally fractured reservoirs and
simulation of multiphase fluid flow therein. In contrast with the classical double-porosity/double permeability models, in
the DFM approach all the interactions and fluid flow in and between the fractures and within the matrix are modeled in a unified
manner, using the same computational grid. There is no need for computing the shape factors, which are crucial to the accuracy
of the double-porosity models. We have exploited this concept in order to develop a new method for the generation of unstructured
computational grids. In the new approach the geological model (GM) of the reservoir is first generated, using square or cubic
grid blocks. The GM is then upscaled using a method based on the multiresolution wavelet transformations that we recently
developed. The upscaled grid contains a distribution of the square or cubic blocks of various sizes. A map of the blocks’
centers is then used with an optimized Delauney triangulation method and the advancing-front technique, in order to generate
the final unstructured triangulated grid suitable for use in any general reservoir simulator with any number of fluid phases. The new method also includes an algorithm for generating fractures
that, contrary to the previous methods, does not require modifying their paths due to the complexities that may arise in spatial
distribution of the grid blocks. It also includes an effective partitioning of the simulation domain that results in large
savings in the computation times. The speed-up in the computations with the new upscaled unstructured grid is about three
orders of magnitude over that for the initial GM. Simulation of waterflooding indicates that the agreement between the results
obtained with the GM and the upscaled unstructured grid is excellent. The method is equally applicable to the simulations
of multiphase flow in unfractured, but highly heterogeneous, reservoirs. 相似文献
16.
Hossein Amani Mohammad Reza Mehrnia Mohammad Hossein Sarrafzadeh Manouchehr Haghighi Mohammad Reza Soudi 《Applied biochemistry and biotechnology》2010,162(2):510-523
There is a lack of fundamental knowledge about the scale up of biosurfactant production. In order to develop suitable technology
of commercialization, carrying out tests in shake flasks and bioreactors was essential. A reactor with integrated foam collector
was designed for biosurfactant production using Bacillus subtilis isolated from agricultural soil. The yield of biosurfactant on biomass (Y
p/x), biosurfactant on sucrose (Y
p/s), and the volumetric production rate (Y) for shake flask were obtained about 0.45 g g−1, 0.18 g g−1, and 0.03 g l−1 h−1, respectively. The best condition for bioreactor was 300 rpm and 1.5 vvm, giving Y
x/s, Y
p/x, Y
p/s, and Y of 0.42 g g−1, 0.595 g g−1, 0.25 g g−1, and 0.057 g l−1 h−1, respectively. The biosurfactant maximum production, 2.5 g l−1, was reached in 44 h of growth, which was 28% better than the shake flask. The obtained volumetric oxygen transfer coefficient
(K
L
a) values at optimum conditions in the shake flask and the bioreactor were found to be around 0.01 and 0.0117 s−1, respectively. Comparison of K
L
a values at optimum conditions shows that biosurfactant production scaling up from shake flask to bioreactor can be done with
K
L
a as scale up criterion very accurately. Nearly 8% of original oil in place was recovered using this biosurfactant after water
flooding in the sand pack. 相似文献
17.
In strong base, e.g., sodium hydride in dimethylformamide, -(-azidobenzoyl)arylamines cyclise in high yield to 2-aryl-1,2-dihydro-3-indazolin-3-ones. 相似文献
18.
An easy, one-pot transformation of Baylis-Hillman adducts into carbamates of unsaturated β-amino acids, for example, 2-(aryl(methoxycarbonylamino)methyl)acrylic acid methyl esters 7 and 2-(methoxycarbonyl aminomethyl)-3-arylacrylic acid methyl esters 8 via reaction with the Burgess reagent is described. 相似文献
19.
The nanocrystalline cubic phase of zirconia was found to be thermally stabilized by the addition of 3 to 40 mol % manganese. The nanocrystalline cubic, tetragonal and monoclinic phases of zirconia stabilized with manganese (III)oxide (Mn‐Stabilized Zirconia) were prepared by thermal decomposition of carbonate and hydroxide precursors. Both the crystallization and isothermal phase transitions associated with Mn‐SZ were studied using high temperature x‐ray diffraction and x‐ray diffraction of quenched samples. Cubic Mn‐SZ initially crystallized and progressively transformed to tetragonal, and monoclinic structures above 700°C. The nanocrystalline cubic Mn‐SZ containing 25 mol % Mn was found to have the greatest thermal stability, retaining its cubic form at temperatures as high as 800°C for periods up to 25 hours. Higher than 40 mol %, cubic Mn2O3 was found to coexist with cubic Mn‐SZ. The crystallite sizes observed for the cubic, tetragonal and monoclinic Mn‐SZ phases ranged from 50 to 137, 130 to 220, and 195 to 450 Å respectively, indicating, for ZrO2, that particle size was a primary factor in determining its polymorphs. The classical Avrami equation for nucleation and growth was applied to the observed phase transformations. 相似文献
20.
Mahmoodi Nosrat O. Zeydi Masoud Mohammadi Mamaghani Manouchehr Montazeri Naser 《Research on Chemical Intermediates》2017,43(4):2641-2651
Research on Chemical Intermediates - A series of new thiocarbamoyl tris-pyrazoline (tripod pyrazoline with triazine core) compounds was obtained by tris-cyclization of chalcone with... 相似文献