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111.
Farzin Emami Mohsen Hatami Alireza Keshavarz Amir Hosein Jafari 《Optical and Quantum Electronics》2009,41(6):429-439
In this paper we simulated the pulse propagation and the switching effects in nonlinear fiber Bragg gratings using a combination
of Fourier series analysis technique and Jacobi iterative method. The effects of nonlinearity and dispersion on the pulse
propagation have been studied extensively. An all optical self switch was designed by this simulation. This switch is operated
based on the input power. 相似文献
112.
The isotopic compositions of carbon compounds in landfill leachate provide insights into the biodegradation pathways that dominate the different stages of waste decomposition. In this study, the carbon geochemistry of different carbon pools, environmental stable isotopes and compound-specific isotope analysis (CSIA) of leachate dissolved organic carbon (DOC) fractions and gases show distinctions in leachate biogeochemistry and methane production between the young area of active waste emplacement and the old area of historical emplacement at the Trail Road Landfill (TRL). The active area leachate has low DOC concentrations (<200 mg l(-1)) dominated by fulvic acid (FA=160 mg l(-1)), and produces CH(4) dominantly by CO(2) reduction (D- excess=20.6 per thousand). Leachate generated in the area of older waste has high DOC (>4770 mg l(-1)) dominated by FA (4482 mg l(-1)) and simple fatty acids (acetic=1008 mg l(-1) and propionic=608 mg l(-1)), and produces CH(4) by the acetate fermentation pathway (D- excess=9.8 per thousand). CSIA shows an advanced degradation and a progressive accumulation of (13)C of fatty acids in leachate from the older area. The enriched (13)C value of FA (-20 and-26 per thousand for the older and active parts, respectively,) and of low molecular weight DOC (-8 and-27 per thousand) as well as of the bulk DOC (-21 and-25 per thousand) shows more advanced degradation in the older part of the landfill, which is consistent with the shift in the humic/FA ratios (0.05 and 0.18). The (13)C enrichment of acetate (-12 per thousand) above the (13)C of DOC (-21 per thousand) and of propionic acid (-19 per thousand), in older leachate, suggests that this acetate has not evolved from the simple degradation of larger organic molecules, but by homoacetogenesis from the enriched dissolved inorganic carbon (DIC) pool (8 per thousand) and H(2,) which produce a more enriched (13)C of acetate. In contrast, the (13)C of the minor acetate in the active area (-17 per thousand) indicates that CO(2)-reducing bacteria must be the primary consumers of H(2), which has resulted in enriched (13)C(DIC) (10 per thousand) and depleted (13)C(CH4) (-58 per thousand). 相似文献
113.
Gholam Hosein Hakimelahi 《Helvetica chimica acta》1982,65(5):1378-1384
The synthesis of some β-lactams and one Δ1-carbapenem is described. The electronic activation of monocyclic β-lactams of type 1 is not sufficient to generate a bioactive compound. 相似文献
114.
115.
Ali Akbar Moshfegh Behnaz Mazandarani Azarmidokht Nahid Gholam Hosein Hakimelahi 《Helvetica chimica acta》1982,65(4):1229-1232
A short synthesis of the title compounds is reported. Most of the compounds prepared were found to be active against a number of pathogenic microorganisms in vitro. 相似文献
116.
Diethyl 2-(ω-hydroxypropyl or butyl) malonates are shown to give 2,20dicarbethoxytetrahydrofuran or tetrahydropyran, when allowed to react with CF3SO2Cl/NEt3 in CH2Cl2. 相似文献
117.
Manavi Mohammad Amin Fathian Nasab Mohammad Hosein Dashti Fatemeh Moghimi Setareh Saniee Parastoo Pouramiri Behjat Foroumadi Alireza Pirali-Hamedani Morteza 《Research on Chemical Intermediates》2022,48(10):4049-4062
Research on Chemical Intermediates - Nearly half of the world's population have been infected with Helicobacter pylori (H. pylori) which is known as the main cause of chronic gastritis,... 相似文献
118.
B.?Yahyaei S.?AzizianEmail author A.?Mohammadzadeh M.?Pajohi-Alamoti 《Journal of the Iranian Chemical Society》2015,12(1):167-174
One of the serious problems in the present century is chemical and biological pollution of the environment. Nanocomposites are multiphase solid materials that have been used as adsorbent of pollutants such as dyes, pesticides, anions and etc. in the last decades. In this study, a novel nanocomposite including silver nanoparticles and ordered mesoporous alumina (OMA) has been synthesized and used for the removal of dyes pollutants (methyl orange, bromothymol blue and reactive yellow) from aqueous solution. The characterization of synthesized nanocomposite has been performed by TEM, N2 adsorption/desorption, XRD and energy dispersive X-ray spectroscopy analysis. The adsorption kinetic and equilibrium data have been obtained by UV–vis spectroscopy. The results show that the silver/OMA nanocomposite (Ag/OMA nanocomposite) is good adsorbent for the removal of anionic dyes from aqueous solution, and also this nanocomposite has a biocidal action against both Gram-negative and Gram-positive bacteria. 相似文献
119.
Nonlinear Dynamics - In this paper, an optimal control scheme, based on dynamic programming strategy, is presented for synchronization of uncertain fractional-order chaotic/hyperchaotic systems. In... 相似文献
120.
Zahra Siyar Ali Motamedzadegan Jafar Mohammadzadeh Milani Ali Rashidinejad 《Molecules (Basel, Switzerland)》2022,27(1)
In this study, the encapsulation of saffron extract (SE) was examined at four various concentrations of soy lecithin (0.5%–4% w/v) and constant concentration of SE (0.25% w/v). Particle size and zeta potential of liposomes were in the range of 155.9–208.1 nm and −34.6–43.4 mV, respectively. Encapsulation efficiency was in the range of 50.73%–67.02%, with the stability of nanoliposomes in all treatments being >90%. Encapsulated SE (2% lecithin) was added to ricotta cheese at different concentrations (0%, 0.125%, 1%, and 2% w/v), and physicochemical and textural properties of the cheese were examined. Lecithin concentration significantly (p ≤ 0.05) affected the particle size, zeta potential, stability, and encapsulation efficiency of the manufactured liposomes. In terms of chemical composition and color of the functional cheese, the highest difference was observed between the control cheese and the cheese enriched with 2% liposomal encapsulated SE. Hardness and chewiness increased significantly (p ≤ 0.05) in the cheeses containing encapsulated SE compared to the control cheese. However, there was no significant difference in the case of adhesiveness, cohesiveness, and gumminess among different cheeses. Overall, based on the findings of this research, liposomal encapsulation was an efficient method for the delivery of SE in ricotta cheese as a novel functional food. 相似文献