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1.
Zohreh Habibi Peyman Salehi Maryam Yousefi Yahya Hejazi Ahmad Laleh Valiollah Mozaffarian Shiva Masoudi Abdolhossein Rustaiyan 《Chemistry of Natural Compounds》2006,42(6):689-692
The hydrodistilled oils from the aerial parts of Ferula latisecta and Mozaffariania insignis, which is endemic to Iran, were analyzed by GC and GC/MS. (Z)-Ocimenone (32.4%), (E)-ocimenone (20.3%), and cis-pinocarvone (11.4%) were the main components among the 22 constituents characterized in the oil of F. latisecta, representing 87.7% of the total components detected. Twenty-five compounds were identified in the oil of M. insignis, representing 99.0% of the total oil, with octyl acetate (41.1%), β-pinene (30.3%), and α-pinene (23.9%) as the main constituents. The essential oils were examined for their potential antimicrobial activities.
Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 561–563, November–December, 2006. 相似文献
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Keyhandokht Karimi-Shahri Laleh Rafat-Motavalli Hashem Miri-Hakimabad 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(2):813-819
This study aimed to investigate effects of the thermoluminescent dosimeter (TLD) size and type on the absorbed dose value by using of Monte Carlo calculations. The options in creating conditions to establish the kerma approximation were also studied. The Monte Carlo N-Particle (MCNPX 2.4.0) transport code was used to design simulations. Results of this work indicate that if common mineral materials of TLDs are replaced by air and a huge volume is applied for the TLD, the accurate assessment of absorbed doses is possible while the photon energy fluence in the TLD cell is convoluted with mass energy absorption coefficients of the real TLD material. In this method the simulation run-time is strongly decreased. 相似文献
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Pierre Apkarian Dominikus Noll Laleh Ravanbod 《Set-Valued and Variational Analysis》2018,26(2):405-429
We use a non-smooth trust-region method for H ∞-control of infinite-dimensional systems. Our method applies in particular to distributed and boundary control of partial differential equations. It is computationally attractive as it avoids the use of system reduction or identification. For illustration the method is applied to control a reaction-convection-diffusion system, a Van de Vusse reactor, and to a cavity flow control problem. 相似文献
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Sanaz Rezaei Afsaneh Valipouri Seyed Abdolkarim Hosseini Ravandi Monireh Kouhi Laleh Ghasemi Mobarakeh 《先进技术聚合物》2019,30(9):2447-2457
Pigmented purpuric dermatosis (PPD) is a skin disorder mainly seen in the lower limbs. The nanofibrous web has been shown to be an appropriate alternative for the treatment of skin diseases as a drug delivery vehicle. In this study, sodium alginate (SA)/polyethylene oxide (PEO) nanofibers containing vitamin C (VC) were fabricated using both blended electrospinning and core/shell electrospinning. The resultant nanofibers were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. Enhancing the VC content resulted in increasing the nanofibers diameter. Also, the degradation rate and drug release were investigated. Drug release was evaluated using the in vitro dissolution and permeation method. The degradation rate and the drug release of the core/shell nanofibers were found to be lower than those of the blended nanofibers. The drug release of the extended nanofibers followed a different pattern, indicating that the extension of the nanofibers could be a promising way to control the drug release. 相似文献
5.
We have developed a 3-phase method for dispersive liquid-liquid microextraction of ß-lactam antibiotics in milk. Chloroform and acetonitrile serve as the solvents for extraction and disperssion, respectively, where Aliquat 336 is the carrier. An experimental design based on Plackett-Burman and Central composite designs were applied for the screening and optimization of significant parameters in the extraction method. The experimental conditions for extraction were optimized, and the subsequent HPLC assay gave relative standard deviations and detection limits in the range of 4.3–8.5 % and 50–500 μg L-1, respectively. Preconcentration factors are in the range of 80–125. Figure
We have developed a 3-phase method for dispersive liquid-liquid microextraction of ß-lactam antibiotics in milk. Chloroform and acetonitrile serve as the solvents for extraction and disperssion, respectively, where Aliquat 336 is the carrier. An experimental design based on Plackett-Burman and Central composite designs were applied for the screening and optimization of significant parameters in the extraction method. 相似文献
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In this study, a simple, rapid, and highly efficient liquid-phase microextraction method based on solidification of floating organic droplet was coupled with high performance liquid chromatography-photo diode array detection (HPLC-PDA) for determination of ketoconazole, clotrimazole, and miconazole as antifungal drugs. Central composite design (CCD) was used for optimization of several factors affecting the extraction efficiency. The optimized conditions were established to be 550 rpm for stirring rate, 35 min for extraction time, 57 °C for extraction temperature, 8.5 for solution pH, 10 μl for organic solvent volume, and 7% (w/v) of NaCl for ionic strength. Limit of detections (LODs) of the extraction method ranged from 0.01 to 0.1 μg L−1 and the linear dynamic ranges (LDRs) ranged from 0.1 to 300 μg L−1 for the three antifungal drugs. Relative standard deviations (RSDs) of the proposed method were 5-11%. Preconcentration factors in the range of 306-1350 were obtained at extraction time of 35 min. Finally, performance of the proposed method was evaluated for the extraction and determination of the drugs’ levels in microgram per liter in samples and satisfactory results were obtained. 相似文献
9.
Laleh Torkian Minoo Dabiri Peyman Salehi Morteza Bararjanian 《Helvetica chimica acta》2011,94(8):1416-1425
The 1‐{[(1H‐1,2,3‐Triazol‐4‐yl)methoxy]phenyl}‐1H‐pyrazolo[1,2‐b]phthalazine‐5,10‐dione derivatives 5 were synthesized by a simple and efficient method, i.e., by the four‐component, one‐pot condensation reaction of phthalohydrazide 4 , a (propargyloxy)benzaldehyde 1 , an active methylene compound 3 (malononitrile or ethyl cyanoacetate), and an azide 2 in the presence of Cu(OAc)2/sodium L ‐ascorbate as catalyst and 1‐methyl‐1H‐imidazolium trifluoroacetate ([Hmim](CF3COO)) as an ionic‐liquid medium in good to excellent yields (Scheme 1). 相似文献
10.
Latifi R Tahsini L Nam W de Visser SP 《Physical chemistry chemical physics : PCCP》2012,14(7):2518-2524
Many enzymes in nature utilize molecular oxygen on an iron center for the catalysis of substrate hydroxylation. In recent years, great progress has been made in understanding the function and properties of iron(IV)-oxo complexes; however, little is known about the reactivity of iron(II)-superoxo intermediates in substrate activation. It has been proposed recently that iron(II)-superoxo intermediates take part as hydrogen abstraction species in the catalytic cycles of nonheme iron enzymes. To gain insight into oxygen atom transfer reactions by the nonheme iron(II)-superoxo species, we performed a density functional theory study on the aliphatic and aromatic hydroxylation reactions using a biomimetic model complex. The calculations show that nonheme iron(II)-superoxo complexes can be considered as effective oxidants in hydrogen atom abstraction reactions, for which we find a low barrier of 14.7 kcal mol(-1) on the sextet spin state surface. On the other hand, electrophilic reactions, such as aromatic hydroxylation, encounter much higher (>20 kcal mol(-1)) barrier heights and therefore are unlikely to proceed. A thermodynamic analysis puts our barrier heights into a larger context of previous studies using nonheme iron(IV)-oxo oxidants and predicts the activity of enzymatic iron(II)-superoxo intermediates. 相似文献