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341.
Intensity noise including Mode Partition Noise (MPN) and Mode Hopping Noise (MHN), and Phase/Frequency Noise Spectrum (FNS) are calculated for a two-mode semiconductor laser. RIN is derived considering of MPN and MHN effect. 相似文献
342.
Hang Nguyen T. V. Mordukhovich Boris S. Sarabi M. Ebrahim 《Journal of Global Optimization》2022,82(1):51-81
This paper addresses problems of second-order cone programming important in optimization theory and applications. The main attention is paid to the augmented Lagrangian method (ALM) for such problems considered in both exact and inexact forms. Using generalized differential tools of second-order variational analysis, we formulate the corresponding version of second-order sufficiency and use it to establish, among other results, the uniform second-order growth condition for the augmented Lagrangian. The latter allows us to justify the solvability of subproblems in the ALM and to prove the linear primal–dual convergence of this method.
相似文献343.
Ebrahim Ghorbani-Kalhor 《Mikrochimica acta》2016,183(9):2639-2647
The author describes the preparation of a magnetic metal organic framework of type MOF-199 containing magnetite (Fe3O4) nanoparticles carrying covalently immobilized 4-(thiazolylazo) resorcinol (Fe3O4@TAR). This material is shown to represent a viable sorbent for separation and preconcentration of Cd(II), Pb(II), and Ni(II) ions. Box-Behnken design was applied to optimize the parameters affecting preconcentration. Following elution with 0.6 mol L?1 EDTA, the ions were quantified by FAAS. The capacity of the sorbent ranged between 185 and 210 mg g?1. The limits of detection are 0.15, 0.40, and 0.8 ng mL?1 for Cd(II), Ni(II), and Pb(II) ions, respectively. The relative standard deviations are <8.5 %. The method was successfully applied to the rapid extraction of trace amounts of these ions from sea food and agri food. 相似文献
344.
Mohammadhassan?MotaghedifardEmail author Mohsen?BehpourEmail author Sayed?Mahdi?Ghoreishi Ebrahim?Honarmand 《Russian Journal of Electrochemistry》2016,52(5):477-487
For the first time, the electrochemical synthesis of gold nanostructures was done at the surface of carbon paste electrode. This device was used as a simple and sensitive electrochemical sensor for measurement of pyridoxine (Vitamin B6, VB6). The diffusion coefficient (D) and the kinetic parameters such as electron transfer coefficient (α) and catalytic rate constant (k) for VB6 were also determined using electrochemical approaches. The cyclic voltammetry method showed VB6 oxidation reaction with irreversible characteristics was diffusion-controlled at low scan rates. Using differential pulse voltammetry (DPV), the peak current was linearly dependent on VB6 concentration in the ranges of 1.9–110.8 and 110.8–257.0 μM, with detection limit of 74.0 nM, respectively. Results showed there is no interference of other vitamins in oxidation of VB6. DPV was used to quantify of VB6 in some real samples by the standard addition method. The modified electrode showed good sensitivity and stability. 相似文献
345.
346.
4-Formylphenyl benzoate was utilized as a versatile precursor for the construction of new series of heterocyclic scaffolds that contain thiazole and thiazolidin-5-one rings. The antibacterial activity of these scaffolds against two types of bacteria was screened and most of them exhibited good activity. Among the synthesized thiazole derivatives, compounds 5, 6, and 8a showed antibacterial activity close to the standard chemotherapeutic (Ampicillin). 相似文献
347.
Ahmad Shaabani Ebrahim Soleimani Zahra Badri 《Monatshefte für Chemie / Chemical Monthly》2006,137(2):181-184
Summary. Silica sulfuric acid as an inexpensive and recyclable solid acid efficiently catalyzes the Fridedl?nder synthesis of quinolines through a condensation reaction of a 2-aminoaryl ketone with an activated α-CH acid compound under
solvent-free conditions in high yields at 100°C. 相似文献
348.
MOHAMMAD-HUSSEIN Sorouraddin MOHAMMAD-REZA Rashidi BEHROOZ Shabani EBRAHIM Ghorbani-Kalhor 《中国化学》2005,23(2):160-165
A new synthesized fluorogenic reagent,8-[(2-pyridine)methylideneamino] quinoline
(PMAQ), was utilized for spectrofluorimetric determination of Cu(II) at trace levels. PMAQ, a good fluorogenic reagent, though insoluble in water, but is soluble in ethanol and 20% ethanol-water. The excitation and the fluorescence wavelengths of PMAQ were 310 and 434 nm respectively. When the reagent was complexed with Cu(II), the fluorescence intensity decreased proportionally with the concentration of Cu(II) at pH 4.5 by a static quenching effect. The highest sensitivity to Cu2+ determination was shown to be at PMAQ
concentration of 1.0×10-5mol•L-1. In order to enhance the quenching effect, the Cu(II)-PMAQ complex solution was kept at 22 ℃ for 20 min. Though the interferences by Co(II) and Fe(III) were very serious, they were however, completely eliminated by being masked with oxalate and ascorbate ions respectively. The linear dynamic range for Cu(II) determination was between 25—441 µg•L-1 with the detection limit of 18 µg•L-1 (RSD=3.7%, n=6). The proposed method was successfully applied to the determination of Cu(II) in real samples including
human blood serum, commercial tea and wheat flour. 相似文献
349.
Ahmad Shaabani Ebrahim Soleimani Ralf-Dieter Hoffmann Rainer Pöttgen 《Tetrahedron letters》2006,47(31):5493-5496
A three-component condensation reaction between an isocyanide, an electron-deficient acetylenic ester and (ethoxycarbonylmethyl)triphenylphosphonium bromide efficiently provides fully substituted N-alkyl-2-triphenylphosphoranylidene glutarimides in a one-pot reaction without any activation or modification. 相似文献
350.
Mothi Mohamed Ebrahim Helen Stoeckli-Evans 《Journal of organometallic chemistry》2007,692(11):2168-2174
Organotin(IV) complexes of the type [RSnCl3(cis-Ph2PCHCHPPh2)] [R = Me (1), nBu (2), Ph (3)] were prepared by the reaction of RSnCl3 with the rigid bisphosphine ligand, cis-1,2-bis(diphenylphosphino)ethylene in dichloromethane. The complexes have been characterized both in solution and the solid state. Low temperature 31P and 119Sn NMR studies indicate two different phosphorus environments. The crystal structures indicate a weak but chelating mode of coordination of the two phosphorus atoms to tin, leading to a distorted octahedral geometry. In solution the complexes 1-3 undergo a redistribution reaction to form [SnCl4(cis-Ph2PCHCHPPh2)] (4) as one of the products. In order to confirm the redistribution, complex 4 has been prepared separately and characterized both structurally and spectrally. 相似文献