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141.
We demonstrate 640 Gbits/s all-optical A AND B, and ā AND B logic functions using pump depletion in a periodically poled lithium niobate waveguide. Bit-error-rate measurements show the effectiveness of the scheme, with a penalty of <2 dB. 相似文献
142.
Iman Manavi-Tehrani Mohammad Rabiee Maryam Parviz Mohammad Reza Tahriri Zahra Fahimi 《Macromolecular Symposia》2010,296(1):457-465
In the present research hydrogel films based on polyvinyl alcohol (PVA) and polyacrylic acid (PAA) blend, with various crosslink densities, have been prepared through different thermal treatment. The results of FTIR and DSC confirmed quality and quantity of conclusion on miscibility of PVA/PAA blends, respectively. Besides, biocompatibility of the samples has been proved in cytotoxicity tests using L929 cells, according to ISO10993–5. Water uptake of the hydrogel blends is measured. pH sensitivity properties of blends are studied with and without boiling in NaOH solutions where the effect of swelling in water before boiling has also been investigated. Preswellings in water and NaOH concentration have been found to be mainly effective on pH sensitivity of PVA/PAA blends. Biocompatibility and pH sensitivity behavior make these hydrogels appropriate candidates to orally deliver drugs such as insulin and peptides that can be released in basic pH of intestine. The stability of these films in acidic solutions and its expansion and also the consequent release of drugs in basic solutions have been studied by using Teofilin as a model drug by UV-spectrophotometeric measurements. 相似文献
143.
Zahra Naji-Azimi Majid Salari Paolo Toth 《European Journal of Operational Research》2010,207(3):1227-1234
In this paper we propose a heuristic method to solve the Capacitated m-Ring-Star Problem which has many practical applications in communication networks. The problem consists of finding m rings (simple cycles) visiting a central depot, a subset of customers and a subset of potential (Steiner) nodes, while customers not belonging to any ring must be “allocated” to a visited (customer or Steiner) node. Moreover, the rings must be node-disjoint and the number of customers allocated or visited in a ring cannot be greater than the capacity Q given as an input parameter. The objective is to minimize the total visiting and allocation costs. The problem is a generalization of the Traveling Salesman Problem, hence it is NP-hard. In the proposed heuristic, after the construction phase, a series of different local search procedures are applied iteratively. This method incorporates some random aspects by perturbing the current solution through a “shaking” procedure which is applied whenever the algorithm remains in a local optimum for a given number of iterations. Computational experiments on the benchmark instances of the literature show that the proposed heuristic is able to obtain, within a short computing time, most of the optimal solutions and can improve some of the best known results. 相似文献
144.
145.
A series of new phosphoramides with general formula RP(O)X2, where R = amino/p‐methylphenoxy and X = amine, were synthesized and characterized by 1H, 13C, 31P nuclear magnetic resonance (NMR), and infrared (IR) spectroscopy and elemental analysis. The 31P{1H} NMR spectra show that among compounds 7–9 containing 2‐, 3‐, and 4‐aminopyridinyl moieties, respectively, the shielding order of the P atom decreases as 7 > 9 > 8 . Also, the structure of compound 7 was determined by X‐ray crystallography. In this structure, repeated noncentrosymmetric dimers are formed by two strong intermolecular N(1)‐H(1N)…N(2) and N(3)‐H(3N)…O(1) hydrogen bonds. Taking into account weak intermolecular C(17)‐H(17C)…N(4), C(17)‐H(17E)…N(4), C(2)‐H(2A)…O(2), and also weak aromatic C—H…C interactions, a three‐dimensional polymeric chain is created in the crystalline network. The density functional theory calculations at B3LYP, B3PW91, and M06 levels using the 6–31+G** basis set were in good agreement with the X‐ray crystallography data. 相似文献
146.
We study acoustic vortex in media with screw dislocation using the Katanaev–Volovich theory of defects. It is shown that the screw dislocation affects the beam?s orbital angular momentum and changes the acoustic vortex strength. This change is a manifestation of topological Dirac phase and is robust against fluctuations in the system. 相似文献
147.
Mehdi M. Baradarani Bahman Ebrahimi Saatluo Shiva Ghabeli Zahra Shokri Masoumeh Shahbazi John A. Joule 《Journal of heterocyclic chemistry》2019,56(7):1999-2007
The tricyclic isatin, 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione, undergoes three‐component, one‐pot reactions with 1‐aryl‐3‐methylpyrazole‐5‐amines and cyclohexane‐1,3‐diones producing hexacyclic spiro products, hexahydrospiro[pyrazolo[3,4‐b]quinoline‐4,1‐pyrrolo[3,2,1‐ij]quinoline‐2′,5(1H,4′H)‐diones]. Comparable spiro condensation products are also obtained using 4‐hydroxy‐2H‐1‐benzopyran‐2‐one in place of cyclohexane‐1,3‐diones. 相似文献
148.
Hamid Goudarziafshar Ahmad Reza Moosavi‐Zare Zahra Jalilian Mehdi Abdolmaleki 《中国化学会会志》2019,66(5):529-534
Nano‐Zn‐[2‐boromophenyl‐salicylaldimine‐methylpyranopyrazole]Cl2 (nano‐[Zn‐2BSMP]Cl2) as a nanoparticle Schiff base complex and a catalyst was introduced for the solvent‐free synthesis of 4‐((2‐hydroxynaphthalen‐1‐yl)(aryl)methyl)‐5‐methyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐ones by the multicomponent condensation reaction of various aromatic aldehydes, β‐naphthol, ethyl acetoacetate, and phenyl hydrazine at room temperature. 相似文献
149.
Sanati Hassan Karamshahi Zahra Ghorbani-Vaghei Ramin 《Research on Chemical Intermediates》2019,45(2):709-726
Research on Chemical Intermediates - This work describes a new method for a one-pot multicomponent condensation of a variety of aldehydes with dimedone and malononitrile in water, providing a... 相似文献
150.
Alizadeh Kaklar Zahra Ansari Mohammad Reza 《Journal of Thermal Analysis and Calorimetry》2019,135(3):1881-1890
Journal of Thermal Analysis and Calorimetry - Two-phase flow was simulated within the effervescent atomizer by the volume of fluid interface tracing model. Different gas-to-liquid mass ratios... 相似文献