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351.
Hydrodistillation–headspace solvent microextraction (HD–HSME) has been used for isolation and preconcentration of the essential
oil from the seeds of Foeniculum vulgare Mill. The effect on extraction efficiency of different conditions, for example sample mass, extraction time, microdrop volume,
and choice of solvent, was studied and all were optimized. The results were compared with those from hydrodistillation, as
reference method. Fourteen compounds were identified; the main components were trans-anethole (70.4%), fenchone (9.3%), and p-allylanisole (8.8%). The results were in good agreement with those obtained by hydrodistillation. 相似文献
352.
Omid Taheri Mahdi Behzad Abolfazl Ghaffari Maciej Kubicki Grzegorz Dutkiewicz Abolfazl Bezaatpour Hossein Nazari Ali Khaleghian Abolfazl Mohammadi Mehdi Salehi 《Transition Metal Chemistry》2014,39(2):253-259
A series of new derivatives and previously reported Schiff base ligands and their oxidovanadium(IV) complexes were synthesized, characterized and tested as potential antibacterial agents against four human pathogenic bacteria. These N2O2 type Schiff base ligands were derived from the condensation of meso-1,2-diphenyl-1,2-ethylenediamine with different salicylaldehyde derivatives, and their metal complexes were obtained from the reaction of these ligands with bis(acetylacetonato)oxidovanadium(IV). Our studies showed that the metal complexes had moderate antibacterial activity, and this activity was higher than that of the free ligands against both Gram-positive and Gram-negative bacteria. Besides, it was found that the presence of more substituents on the ligands increases the antibacterial activities of both the free ligands and their complexes. The crystal structures of H2L4 and its corresponding complex VOL4 were determined by X-ray crystallography. 相似文献
353.
A comprehensive review considering recent advances in self‐collimation and its applications in optical integration is covered in the current article. Self‐collimation is compared to the conventional technique of photonic bandgap engineering to control the light propagation in photonic crystal‐based structures. It is fully discussed how the self‐collimation phenomenon can be tailored to be independent of the incident angle and polarization. This adds substantial flexibility to the structure to overcome light coupling challenges and simultaneously aids in the omission of bulk and challenging elements, including polarizers and lenses from optical integrated circuits. Additionally, designed structures have the potential to be rescaled to operate in any desired frequency range thanks to the scalability rule in the field of electromagnetics. Moreover, it is shown that one can boost the coupling efficiency by applying an anti‐reflection property to the structure, which provides not only efficient index matching but also the matching between external waves with uniform amplitude and Bloch waves with periodic amplitude. 相似文献
354.
Minoo Dabiri Peyman Salehi Mostafa Baghbanzadeh 《Monatshefte für Chemie / Chemical Monthly》2007,43(7):1191-1194
2,3-Dihydroquinazolin-4(1H)-ones were efficiently synthesised by the reaction of isatoic anhydride, a primary amine or ammonium acetate, and different
aromatic aldehydes in 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) without using any acidic catalyst. Also a bis-derivative of the title compound as a polyheterocyclic system was synthesised
successfully in high yield. 相似文献
355.
356.
In this paper, within the scope of FRW cosmology for $k=0, \pm 1$ , we investigate the dynamics of the universe in cosmological model where a scalar field nonminimally is coupled to matter field. By best-fitting the model parameters with the observational data, for the direct interaction between the dark sectors in the model, we obtain new constraints on cosmological parameters. The result with the best fitted model parameters supports the current universe acceleration in all models and shows that only in flat universe case the phantom crossing occurs twice in the past and once in the future. The best fitted reconstructed potential function and other physical functions are also obtained. 相似文献
357.
Shafaati Mahsa Miralinaghi Mahsasadat Shirazi Reza Haji Seyed Mohammad Moniri Elham 《Research on Chemical Intermediates》2020,46(12):5231-5254
Research on Chemical Intermediates - The environmental pollution caused by the introduction of antibiotics into the water resources poses serious threats to aquatic organisms and human... 相似文献
358.
Kheirollahivash Mahsa Rashidi Fariborz Moshrefi Mohammad Mahdi 《Plasma Chemistry and Plasma Processing》2019,39(2):445-459
Plasma Chemistry and Plasma Processing - Hydrogen and solid carbon were produced through methane decomposition in a plasma reactor with a parallel set of screw type helix and rod-like electrodes.... 相似文献
359.
Mahsa Kiani Mojtaba Bagherzadeh Soraya Meghdadi Farzaneh Fadaei-Tirani Kurt Schenk-Joß Navid Rabiee 《应用有机金属化学》2020,34(4):e5531
The complexes PdII(qcq)(OAc) and PtII(qcq)Cl have been synthesized using environmentally benign synthesized ligands and characterized by elemental analyses: Fourier transform infrared spectroscopy, UV–visible spectroscopy, 1H NMR spectroscopy, and X-ray diffraction. The catalytic activity of the complex was assessed, in different media, for the Mizoroki–Heck coupling reaction for typical aryl halides and terminal olefins under aerobic conditions. Since the base and the solvent were found to influence the efficiency of the reaction, reaction conditions, temperature, time, and the amount of K3PO4 and a mixture of H2O/PEG, were optimized. We found, for the Mizoroki–Heck reaction coupling less reactive aryl chloride derivatives with olefins, promising activity for palladium catalysts. The electrochemical behavior of Hqcq and the Pd(II) complex was investigated by cyclic voltammetry and irreversible PdII/I reductions were observed. Hqcq and the Pd(II) and Pt(II) complexes were also screened for their in vitro antibacterial activity. They showed promising antibacterial activity comparable to that of the antibiotic penicillin. 相似文献
360.
Khalili Asboei Alireza Salehi Amiri Seyed Sadegh 《Czechoslovak Mathematical Journal》2022,72(3):747-750
Czechoslovak Mathematical Journal - We prove that if the average number of Sylow subgroups of a finite group is less than $${{41} \over 5}$$ and not equal to $${{29} \over 4}$$ , then G is solvable... 相似文献