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111.
Hassan Hassanabadi Won Sang Chung Soroush Zare Hadi Sobhani 《The European Physical Journal C - Particles and Fields》2018,78(1):83
This paper contains a discussion of a relativistic spin-0 system in the presence of a Gödel-type background space-time. The Duffin–Kemmer–Petiau (DKP) equation in the presence of a Gödel-type background space-time is studied in detail. After a derivation of the final form of this equation in the considered framework, free spin-0 particles have been studied. 相似文献
112.
Rashba effect in presence of a time-dependent interaction has been considered.Then time-evolution of such a system has been studied by using Lewis–Riesenfeld dynamical invariant and unitary transformation method.So appropriate dynamical invariant and unitary transformation according the considered system have been constructed as well as some special cases have come into this article which are common in physics. 相似文献
113.
Hadi Beitollahi Alireza Mohadesi Mortaza Mostafavi Hassan Karimi-Maleh Mehdi Baghayeri Ali Akbari 《Ionics》2014,20(5):729-737
A novel carbon paste electrode modified with carbon nanotubes and 5-amino-2′-ethyl -biphenyl-2-ol was fabricated. The electrochemical study of the modified electrode, as well as its efficiency for electrocatalytic oxidation of ascorbic acid (AA), is described. The electrode was employed to study the electrocatalytic oxidation of AA, using cyclic voltammetry, chronoamperometry, and square-wave voltammetry (SWV) as diagnostic techniques. It has been found that the oxidation of AA at the surface of modified electrode occurs at a potential of about 250 mV less positive than that of an unmodified carbon paste electrode. SWV exhibits a linear dynamic range from 2.0?×?10?7 to 5.0?×?10?4 M and a detection limit of 1.0?×?10?7 M for AA. In addition, this modified electrode was used for simultaneous determination of AA, acetaminophen (AC), and tryptophan (TRP). Finally, the modified electrode was used for determination of AA, AC, and TRP in pharmaceutical products. 相似文献
114.
Abdollahi A Hassani A Ghosta Y Bernousi I Meshkatalsadat MH Shabani R Ziaee SM 《Natural product research》2012,26(1):77-83
The effects of postharvest spraying of essential oils from sweet basil (Ocimum basilicum), fennel (Foeniculum vulgare), summer savory (Satureja hortensis) and thyme (Thymus vulgaris) on fungal decay and quality parameters of the 'Thompson seedless' table grape stored at 0?±?1°C for 60 days were evaluated. Results showed that the essential oils, especially of thyme and fennel, have a good inhibitory effect on the development of fungal decay in Thompson table grapes. In addition, essential oils reduced weight loss, berry and rachis browning and had no considerable adverse effect on the flavour of the fruits. GC-MS analysis showed that the main compounds identified in sweet basil, fennel, summer savory and thyme oils are linalool (65.25%), trans-anethole (64.72%), carvacrol (54.14%) and β-ocimene (12.62%), respectively. Therefore, these essential oils have good potential for use as an alternative to synthetic fungicides for the preservation and storage of table grapes. 相似文献
115.
In this study, the application of various concentrations (0.02%, 0.04%, 0.06% and 0.08%) of Satureja khuzestanica essential oil (EO) was examined on the oxidative stability of sunflower oil and compared to butylated hydroxyanisole (BHA) during storage at 60°C. Gas chromatography (GC) and GC-mass spectrometry analyses of the oils revealed that carvacrol (87.7%) was the major component of EO. Peroxide value and anisidine value measurements in sunflower oil showed that all concentrations of EO had antioxidant effects in comparison to BHA. Oil samples supplemented with EO concentration of 0.08% were the most stable during storage (p?0.05). EO also was able to reduce the stable free radical 2, 2-diphenyl-1-picrylhydrazyl with a 50% inhibition concentration (IC??) of 31.5?±?0.6?μg?mL?1. Therefore, the results indicate that EO could be used as a natural antioxidant in food lipids. 相似文献
116.
Hamid Golchoubian Zahra Mohseni Afshar Golasa Moayyedi Giuseppe Bruno Hadi Amiri Rudbari 《中国化学》2012,30(8):1873-1880
The syntheses of three mixed ligand chelate copper(II) complexes of the type [Cu(L)(acac)(H2O)]BPh4 where acac=acetyleacetonate; L=N,N‐dimethyl,N′‐benzylethane‐1,2‐diamine ( L1 ), N,N‐dimethyl, N′‐2‐methylbenzylethane‐1,2‐diamine ( L2 ) or N,N‐dimethyl,N′‐2‐chlorobenzylethane‐1,2‐diamine ( L3 ) are reported and characterized by elemental analyses, spectroscopic and molar conductance measurements. The X‐ray structure of complex 1 shows that the central copper atom is placed in a distorted square pyramidal geometry made by acac and diamine chelate in the base and a H2O molecule on the apex. The prepared complexes are fairly soluble in a large number of organic solvents and show positive solvatochromism. Calculations of SMLR (stepwise multiple linear regression) method was utilized to find the best model explaining the observed solvatochromic behavior and showed that among different solvent parameters, donor number (DN) is a dominant factor responsible for the shift in the d‐d absorption band of the complexes to the lower wavenumber with increasing its values. The importance of substituent effect in diamine ligand on the spectral and SMLR measurements is also discussed. 相似文献
117.
Cell formation (CF) is the first and the most important problem in designing cellular manufacturing systems. Due to its non-polynomial nature, various heuristic and metaheuristic algorithms have been proposed to solve CF problem. Despite the popularity of heuristic algorithms, few studies have attempted to develop exact algorithms, such as branch and bound (B&B) algorithms, for this problem. We develop three types of branch and bound algorithms to deal with the cell formation problem. The first algorithm uses a binary branching scheme based on the definitions provided for the decision variables. Unlike the first algorithm, which relies on the mathematical model, the second one is designed based on the structure of the cell formation problem. The last algorithm has a similar structure to the second one, except that it has the ability to eliminate duplicated nodes in branching trees. The proposed branch and bound algorithms and a hybrid genetic algorithm are compared through some numerical examples. The results demonstrate the effectiveness of the modified problem-oriented branch and bound algorithm in solving relatively large size cell formation problems. 相似文献
118.
Along the same line as that in Ono (Ann Pure Appl Logic 161:246–250, 2009), a proof-theoretic approach to Glivenko theorems is developed here for substructural predicate logics relative not only to classical predicate logic but also to arbitrary involutive substructural predicate logics over intuitionistic linear predicate logic without exponentials QFL e . It is shown that there exists the weakest logic over QFL e among substructural predicate logics for which the Glivenko theorem holds. Negative translations of substructural predicate logics are studied by using the same approach. First, a negative translation, called extended Kuroda translation is introduced. Then a translation result of an arbitrary involutive substructural predicate logics over QFL e is shown, and the existence of the weakest logic is proved among such logics for which the extended Kuroda translation works. They are obtained by a slight modification of the proof of the Glivenko theorem. Relations of our extended Kuroda translation with other standard negative translations will be discussed. Lastly, algebraic aspects of these results will be mentioned briefly. In this way, a clear and comprehensive understanding of Glivenko theorems and negative translations will be obtained from a substructural viewpoint. 相似文献
119.
120.
Bahaedin Nikrooz Morteza Zandrahimi Hadi Ebrahimifar 《Journal of Sol-Gel Science and Technology》2012,63(3):286-293
Silica coating for the protection of stainless steel (SS) surfaces was prepared using tetraethoxysilane and methyltriethoxysilane as precursors via an acid-catalysed (H2SO4) sol?Cgel method and was deposited on ferritic SS AISI 430 by dip coating. The surface morphology was studied using a scanning electron microscope equipped with energy-dispersive X-ray, phase analysis was carried out by X-ray diffraction, and isothermal oxidation was carried out at 800?°C for 200?h. Corrosion properties were examined by electrochemical impedance spectroscopy and resistance polarization methods in an aqueous medium containing 3.5?wt?% NaCl. The results indicated that silica coating improved high-temperature oxidation resistance of AISI 430 in chloride media. 相似文献