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481.
Somayeh Sharifi Zarei Ebrahim Asghari Alireza 《Russian Journal of Electrochemistry》2021,57(2):183-196
Russian Journal of Electrochemistry - In the present study, simultaneous voltammetric determination of noscapine and papaverine as two important alkaloids in opium was studied for the first time. A... 相似文献
482.
Heydari Zahra Abdy Hamed Ghaziani Mohammad Pouya Kolahdouz Mohammadreza Asl-Soleimani Ebrahim Masnadi-Shirazi Mostafa 《Journal of Solid State Electrochemistry》2021,25(2):583-590
Journal of Solid State Electrochemistry - Organometallic halide perovskites have been arisen as a class of multi-purpose materials with exciting applications in optoelectronic devices such as solar... 相似文献
483.
Let τ be a locally convex topology on the countable dimensional polynomial ${\mathbb{R}}$ -algebra ${\mathbb{R} [\underline{X}] := \mathbb{R} [X_1, \ldots, X_{n}]}$ . Let K be a closed subset of ${\mathbb{R} ^{n}}$ , and let ${M := M_{\{g_1, \ldots, g_s\}}}$ be a finitely generated quadratic module in ${\mathbb{R} [\underline{X}]}$ . We investigate the following question: When is the cone Psd(K) (of polynomials nonnegative on K) included in the closure of M? We give an interpretation of this inclusion with respect to representing continuous linear functionals by measures. We discuss several examples; we compute the closure of ${M = \sum \mathbb{R} [\underline{X}]^{2}}$ with respect to weighted norm-p topologies. We show that this closure coincides with the cone Psd(K) where K is a certain convex compact polyhedron. 相似文献
484.
Venkata Ramaiah‐Badarla Adolfo Esteban‐Martin Majid Ebrahim‐Zadeh 《Laser \u0026amp; Photonics Reviews》2013,7(5):L55-L60
A self‐phase‐locked degenerate femtosecond optical parametric oscillator (OPO) based on the birefringent nonlinear material, bismuth triborate, BiB3O6, synchronously‐pumped by a Kerr‐lens‐mode‐locked Ti:sapphire laser at 800 nm is described. By exploiting versatile phase‐matching properties of BiB3O6, including large spectral and angular acceptance for parametric generation and low group velocity dispersion in the optical xz plane, stable self‐phase‐locked degenerate OPO operation centered at 1600 nm is demonstrated using collinear type I (e → oo) interaction in a 1.5‐mm crystal at room temperature. The degenerate OPO output spectrum extends over 46 nm (∼5.4 THz) with 190 fs pulse duration for input pump pulses of 155 fs with a bandwidth of 7 nm. Phase coherence between the pump and degenerate output is verified using f‐2f interferometry, and discrete frequency beats caused by different carrier‐envelope‐offset frequencies are measured using radio frequency measurements. Photo shows a 1.5‐mm BiB3O6 crystal used as a nonlinear gain medium in a degenerate self‐phase‐locked femtosecond OPO operating at room temperature. The green beam is the result of non‐phase‐matched sum‐frequency mixing between the pump light and the sub‐harmonic OPO field at degeneracy. 相似文献
485.
Javad Azizian Ali A. Mohammadi Ebrahim Soleimani Ali R. Karimi Mohammad R. Mohammadizadeh 《Journal of heterocyclic chemistry》2006,43(1):187-190
A mild and stereoselective three‐component one‐step synthesis of cis‐isoquinolonic acid using silica sulfuric acid as a heterogeneous catalyst from an aldehyde, amine and homophthalic anhydride in acetonitrile is described. This new method produces pure products in high yields (81‐91%). 相似文献
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Let G be a locally compact group, and ZL1(G) be the centre of its group algebra. We show that when G is compact ZL1(G) is not amenable when G is either non-abelian and connected, or is a product of infinitely many finite non-abelian groups. We also, study, for some non-compact groups G, some conditions which imply amenability and hyper-Tauberian property, for ZL1(G). 相似文献
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