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121.
In this paper, a single optical ring resonator connected to a Sagnac loop is used to demonstrate theoretically a novel narrow band optical filter response that is based on Sagnac phase-shift Δφ. The given filter structure permits the Sagnac rotation to control the filter response. It is shown that by changing the Sagnac rotation rate, we can tune the filter response for desired bandwidths. To increase the wavelength selectivity of the filter, the Sagnac phase-shift should be as small as possible that is limited by the loop length. For Δφ=0.1 rad, the obtained FWHM is 2.63 MHz for tuning loop length of 2 m. The simulation response agrees fairly with the recently reported experimental result. 相似文献
122.
Brendan Goldsmith Fatemeh Karimi Ahad Mehdizadeh Aghdam 《Czechoslovak Mathematical Journal》2013,63(3):819-831
In this paper we investigate two new classes of torsion-free Abelian groups which arise in a natural way from the notion of a torsion-free Crawley group. A group G is said to be an Erd?s group if for any pair of isomorphic pure subgroups H,K with G/H ? G/K, there is an automorphism of G mapping H onto K; it is said to be a weak Crawley group if for any pair H,K of isomorphic dense maximal pure subgroups, there is an automorphism mapping H onto K. We show that these classes are extensive and pay attention to the relationship of the Baer-Specker group to these classes. In particular, we show that the class of Crawley groups is strictly contained in the class of weak Crawley groups and that the class of Erd?s groups is strictly contained in the class of weak Crawley groups. 相似文献
123.
Fatemeh Mohammadi 《代数通讯》2013,41(10):3753-3764
In this article, Cohen–Macaulay chordal graphs and generalized star graphs are studied to show that all powers of the vertex cover ideal of such graphs have linear quotients. Moreover, it is shown that the Alexander dual of the clique complex of any chordal graph is vertex decomposable. 相似文献
124.
Fatemeh Fattahi 《佛山科学技术学院》2013,5(3):327-333
At the present paper, the new concepts of fuzzy quasi norm, fuzzy Banach space, fuzzy quasi continuity and fuzzy quasi boundedness is introduced. Furthermore, we define the fuzzy quasi operator norm and also it is shown that the set all of fuzzy quasi bounded operator from X to Y is fuzzy quasi Banach space. Finally, we have introduced and investigated some notions and some results on *-algebra theory. 相似文献
125.
126.
Mina Neghabi Abbas Behjat Bi Bi Fatemeh Mirjalili Leila Zamani 《Current Applied Physics》2013,13(1):302-306
One of the porphyrin derivatives, meso-tetraphenylporphyrin (TPP), has been synthesized and examined as an emitter material (EM) for efficient fluorescent red organic light-emitting diodes (OLEDs). By inserting a tungsten oxide (WO3) layer into the interface of anode (ITO) and hole transport layer N,N′-Di-[(1-napthyl)-N,N′-diphenyl]-(1,1′-biphenyl)-4,4′-diamine (NPB) and by using fullerene (C60) in contact with a LiF/Al cathode, the performance of devices was markedly improved. The current density–voltage–luminance (J–V–L) characterizations of the samples show that red OLEDs with both WO3 and C60 as buffer layers have a lower driving voltage and higher luminance compared with the devices without buffer layers. The red OLED with the configuration ITO/WO3 (3 nm)/NPB (50 nm)/TPP (60 nm)/BPhen (30 nm)/C60 (5 nm)/LiF (0.8 nm)/Al (100 nm) achieved the high luminance of 6359 cd/m2 at the low driving voltage of 8 V. At a current density of 20 mA/cm2, a pure red emission with CIE coordinates of (0.65; 0.35) is observed for this device. Moreover, a power efficiency of 2.07 lm/W and a current efficiency of 5.17 cd/A at 20 mA/cm2 were obtained for the fabricated devices. The study of the energy level diagram of the devices revealed that the improvement in performance of the devices with buffer layers could be attributed to lowering of carrier-injecting barrier and more balanced charge injection and transport properties. 相似文献
127.
In this investigation, a facile sonochemical route has been developed for the preparation of silver vanadium oxide (SVO) micro/nanorods by using silver salicylate and ammonium metavanadate as silver and vanadate precursor, respectively. Here, silver salicylate, [Ag(HSal)], is introduced as a new silver precursor to fabricate AgVO3 nanorods. The effect of numerous solvents and surfactants on the morphology and sonochemical formation mechanism of AgVO3 nanorods was studied. AgVO3 nanorods were characterized by SEM and TEM images, XRD patterns, FT-IR, XPS, and EDS spectroscopy. SEM, TEM, and XRD results showed that AgO nanoparticles were formed onto AgVO3 nanorods in the presence of ethanol, cyclohexanol, dimethylsulfoxide (DMSO), and acetone. By using polyethylene glycol (PEG-6000) and N,N-dimethylformamide (DMF) as organic additives, the thickness of AgVO3 nanorods decreased. 相似文献
128.
Davar M. Boghaei Fatemeh Behzadian-Asl Hamid Reza Khavasi 《Journal of chemical crystallography》2008,38(4):311-314
Abstract The chemical preparation and crystal structure for a 4,4′-azodi(phenylcyanamide) salt) in the solid state are reported. This
compound crystallizes in the triclinic space group P
with the following unit cell parameters: a = 9.759(3) ?, b = 11.237(4) ?, c = 11.919(4) ?, α = 95.54(3)°, β = 98.50(3)°, γ = 109.39(2)°, Z = 1 and V = 1204.4(7) ?3. The 4,4′-azodi(phenylcyanamide) dianion, azodicyd2−, is approximately planar, with the cyanamide groups (–N=C=N) in an anti conformation relative to each other and the azo group (–N=N–) adopting the more thermodynamically stable trans conformation. The crystal X-ray analysis shows that there are one azo molecule cation, two tetrabutylammonium cations and
one water molecule in unit cell. Intermolecular O–H···N hydrogen bonds may be effective in the stabilization of the crystal
structure of this compound and to form linear chain structure in the packing.
Index Abstract Synthesis and crystal structure of Bis (Tetrabutylammonium)(4,4′-Azodi(phenylcyanamide)) salt . [(n-Bu)4N]2[Azodicyd2-] · H2O
Davar M. Boghaei 1*, Fatemeh Behzadian-Asl 1 and Hamid Reza Khavasi2
1 Department of Chemistry, Sharif University of Technology, P.O. Box 11155-9616, Tehran, Iran
2 Department of Chemistry, Shahid Beheshti University, Evin, Tehran 1983963113, Iran
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
129.
Fazaeli Yousef Hosseini Mohammad Amin Shahabinia Fatemeh Feizi Shahzad 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(1):201-207
Journal of Radioanalytical and Nuclear Chemistry - Porphyrins and 68Ga have emerged as novel synergic options for PET applications so the idea of preparation of a novel porphyrin complex using this... 相似文献
130.
Karami Fatemeh Ahmadi Nadooshan Afshin Westerberg Lars G. Tadi Beni Yaghoub 《Journal of Thermal Analysis and Calorimetry》2019,137(1):327-342
Journal of Thermal Analysis and Calorimetry - This study was conducted with the aim of investigating the Newtonian nanofluid flow in a catheterized tapered artery through using a completely... 相似文献