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101.
Esmael Rostami Davood Heidaryan Hanif Fattahi Abbas Shockravi Mehdi Zarei Farokh Rakhshanderu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1924-1934
Four new dinaphthosulfide and dibenzosulfide aza podands were synthesized. The synthesis of these podands was performed under three different reaction conditions: 1) diester, K 2 CO 3 , methanol, and RT; 2) diester, ethanolamine, and microwave (MW); and 3) diacid dichloride, ethanolamine, Et 3 N, CH 2 Cl 2 , RT. Two kinds of diester (dinaphthosulfide and dibenzosulfide) were used for the preparation of dihydroxy podands. These dihydroxy podands were reacted with thionyl chloride to afford dichloro podands. The second route gave excellent yields of dihydroxy podands. Dichloro podands are more soluble than dihydroxy podands in conventional solvents such as methanol, chloroform, and acetonitrile. 相似文献
102.
Ghasem Aghapour Ameneh Asgharzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):796-802
AbstractA simple, highly selective and efficient method is described for the conversion of primary alcohols, tetrahydropyranyl and silyl ethers to thiocyanates by use of chlorodiphenylphosphine and ammonium thiocyanate. Secondary substrates produce both the two isomeric products, thiocyanate and isothiocyanate, while tertiary ones give isothiocyanates as the only products by this new method. In contrast to previously reported methods based on trivalent phosphorus for this transformation, the present method does not require an electrophile in the presence of trivalent phosphorus (ClPPh2). The order of activity of these substrates is silyl ether> alcohol > tetrahydropyranyl ether. The present method not only interestingly distinguishes between primary, secondary and tertiary substrates but also converts them to the corresponding thiocyanates with excellent chemoselectivity in the presence of several other functional groups. 相似文献
103.
104.
Erfani Hamidreza Karimi Malekabadi Abtin Ghazanfari Mohammad Hossein Rostami Behzad 《Transport in Porous Media》2021,136(2):471-494
Transport in Porous Media - Gravity drainage is known as the controlling mechanism of oil recovery in naturally fractured reservoirs. The efficiency of this mechanism is controlled by... 相似文献
105.
Ghasem Marandi Malek T. Maghsoodlou Nourallah Hazeri Sayyed M. Habibi-Khorassani Niloufar Akbarzadeh Torbati Faramarz Rostami-Charati Brian W. Skelton Mohamed Makha 《Molecular diversity》2011,15(1):197-201
Abstract
In a new multicomponent reaction phenanthridine reacts with isocyanides and malonitrile in the presence of benzaldehyde derivatives to produce 2-aryl-3-(alkyl- or arylimino)-2,3-dihydropyrrolo[1,2-f]phenanthridine-1,1(12b H)-dicarbonitrile in a simple, mild, and efficient protocol in excellent yields. 相似文献106.
A. S. Pahlevanyan H. R. Rostami 《Journal of Contemporary Mathematical Analysis (Armenian Academy of Sciences)》2011,46(2):106-112
The paper gives a construction of a free monoid of rank 2 in the group of automorphisms of free periodic groups B(m, n) of any odd period n ≥ 665 and any rank m > 1.Moreover, it is proved that if the period is any prime numbern > 1003 and the group B(m, n) is nested in some n-periodic group G as a normal subgroup, then B(m, n) is a direct factor in G. 相似文献
107.
In this paper, nonclassical light propagation through passive optical coupler is investigated. On the other hand, passive optical device design for nonclassical light is analyzed in this work. Effect of mode mismatching including mismatching in propagation constant on operation of the considered device is studied. We investigate different separable and entangled input excitations with single photons in this case. We specially study the measure of entanglement and effect of propagation constant mismatch on it. The simultaneous effect of loss and mismatch is also studied. Obtained results for different excitation states illustrate that there is a possibility to design such that the system operation can be immune versus fabrication imperfections. 相似文献
108.
The 4,5-dihydroisoxazole-5-acetic acids 4a-j were prepared from the ketoximes 1a-j, 2,2-dimethyl-5-methoxymethylene-1,3-dioxan-4,6-dione (2) and butyllithium in yields from 35 to 79%. 相似文献
109.
We tackle precedence-constrained sequencing on a single machine in order to minimize total weighted tardiness. Classic dynamic programming (DP) methods for this problem are limited in performance due to excessive memory requirements, particularly when the precedence network is not sufficiently dense. Over the last decades, a number of precedence theorems have been proposed, which distinguish dominant precedence constraints for a job pool that is initially without precedence relation. In this paper, we connect and extend the findings of the foregoing two strands of literature. We develop a framework for applying the precedence theorems to the precedence-constrained problem to tighten the search space, and we propose an exact DP algorithm that utilizes a new efficient memory management technique. Our procedure outperforms the state-of-the-art algorithm for instances with medium to high network density. We also empirically verify the computational gain of using different sets of precedence theorems. 相似文献
110.
Neda Naderkhani Sasan Rostami Zahra Mokhtari Majid Mollavali Mohammad Nourany 《先进技术聚合物》2024,35(2):e6319
The need for higher energy storage capability has encouraged researchers to move toward lithium-metal batteries (LMBs). Due to the safety issue associated with liquid electrolytes, solid polymer electrolytes (SPEs) the main focus on polyethylene oxide (PEO) were at the center of the research. However, high crystallization, fast decomposition, and low thermomechanical stability has limited its application. Low lithium-ion transference number ( ) is another issue leading to polarization of the SPEs and consequently, triggering dendrite nucleation and growth. Here, we developed a series of SPEs based on PEO-waterborne polyurethane (WPU) and nanoparticles of fluorine-doped carbon quantum dot (fCQD) and MXene. The host polymer matrix was a blend of poly(ε-caprolactone) (PCL)-based WPU and PEO. The use of WPU and the nanoparticles increased the thermomechanical stability and suppressed PEO crystallinity through disrupting the spherulites growth and reducing the thermal stability of the crystallites. Using the WPU led to significant increase in ( ) compared with previous reports. The prepared SPEs showed high-electrochemical stability and ionic conductivity at and based on the results of cycling performance, a discharge capacity of 120.58 mAh/g and coulombic efficiency of 99.1% was achieved after 200 cycles. 相似文献