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61.
Younes Ghasemi Abdolali Mohagheghzadeh Zahra Ostovan Maryam Moshavash Sara Rasoul-Amini Mohammad Hossein Morowvat 《Chemistry of Natural Compounds》2010,46(5):734-737
Biotransformation of several monoterpene ketones, including carvone, pulegone, piperitone, menthone, and fenchone, was carried
out by the locally isolated unicellular microalgae Chlorella vulgaris. The microalgal strain was isolated during a screening program from soil samples collected from paddy-fields of Fars Province,
in the south of Iran. Chlorella vulgaris was cultured in 250 mL conical flasks, each containing 50 mL of BG-11 liquid medium and 20 μL levels of terpene substrates,
incubated at a temperature of 28±2°C and illuminated continuously with fluorescent lamps with shaking at 80 rpm. The metabolites
were identified by thin-layer chromatography and GC-MS. Chlorella vulgaris has the ability to reduce the C=C double bond of carvone to yield trans-dihydrocarvone and cis-dihydrocarvone. The cell line reduced menthone and pulegone to the same product and gave menthol. Study of Chlorella vulgaris with substrates of piperitone and fenchone showed no reaction in these substrates. Chlorella vulgaris MCCS 012 was assigned according to the 18S rRNA gene sequence. The DNA sequence of the 18S rRNA gene of Chlorella vulgaris MCCS 012 was recorded in the NCBI under the accession number EU374170. 相似文献
62.
Mohammad Kazem Mohammadi Shahriare Ghammamy Soroush Zarrinabadi Mohammad Hossein Farjam Behrang Sabayan 《中国化学》2010,28(11):2199-2203
New orange solid tributylammonium halochromates, (C4H9)3N+CrO3X?, TBAXC (X=F, Cl) are easily synthesized by the reaction of tributylammonium fluoride and chloride with CrO3 in a 1:1 molar ratio in the presence of HF and HCl. Tributylammonium halochromates(VI) are versatile reagent for the effective and selective oxidation of organic substrates. Silica gel supported TBAFC and TBACC are versatile reagents for the effective and selective oxidation of organic substrates, in particular, thiols, under mild conditions. Considerable improvements are observed in the presence of the absorbent, making the work‐up much more convenient. 相似文献
63.
Hossein Mahdavi Farid Sheikh-Hasani Mehdi Mahmoudian 《Journal of the Iranian Chemical Society》2016,13(9):1733-1740
Hyperbranched polyester-grafted poly(vinylidene fluoride) (HBPE-g-PVDF) was synthesized and used as additive in preparation of PVDF blend membranes. HBPE-g-PVDF copolymer was characterized with FTIR and TGA techniques. The prepared membranes were also characterized with SEM, AFM and contact angle measurement. The performance of prepared membranes as nanofiltration membrane was studied by pure water flux (PWF), salt rejection, dynamic and static fouling tests. The results showed that hydrophilicity of prepared membranes greatly increased after blending, and their pore size and pore size distribution and so PWF of blend membranes increased. 相似文献
64.
Mahboubeh Rahmati-Rostami Cyrus Ghotbi Masih Hosseini-Jenab Amir Naser Ahmadi Amir Hossein Jalili 《The Journal of chemical thermodynamics》2009,41(9):1052-1055
The solubility of hydrogen sulphide in three ionic liquids, viz. 1-hexyl-3-methylilmidazolium hexafluorophosphate ([hmim][PF6]), 1-hexyl-3-methylimidazolium tetrafluoroborate ([hmim][BF4]), and 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([hmim][Tf2N]), at temperatures ranging from 303.15 K to 343.15 K and pressures up to 1.1 MPa were determined. The solubility values were correlated using the Krichevsky–Kasarnovsky equation and Henry’s constants were obtained at different temperatures. Partial molar thermodynamic functions of solvation such as standard Gibbs free energy, enthalpy, and entropy were calculated from the solubility results. Comparison of the values obtained show that the solubility of H2S in these three ionic liquids was in the sequence: [hmim][BF4] > [hmim][PF6] ≈ [hmim][Tf2N]. 相似文献
65.
In this paper, a decentralized adaptive control scheme for multi-robot coverage is proposed. This control method is designed based on centroidal Voronoi configuration integrated with robust adaptive fuzzy control techniques. We consider simple single integrator mobile robots used for covering dynamical environments, where an adaptive fuzzy logic system is used to approximate the unknown parts of control law. A robust coverage criterion is used to attenuate the adaptive fuzzy approximation error and measurement noises to a prescribed level. Therefore, the robots motion is forced to obey solutions of a coverage optimization problem. The advantages of the proposed controller can be listed as robustness to external disturbances, computation uncertainties, and measurement noises, while applicability on dynamical environments. A Lyapunov-function based proof is given of robust stability, i.e. convergence to the optimal positions with bounded error. Finally, simulation results are demonstrated for a swarm coverage problem simultaneous with tracking mobile intruders. 相似文献
66.
Farhad Shirini Nader Ghaffari Khaligh Gholam Hossein Imanzadeh Parisa Ghods Ghasem-Abadi 《中国化学快报》2012,23(10):1145-1148
1,3-Dibromo-5,5-dimethylhydantoin,has been used as an efficient catalyst for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes in the presence of kaolin.All reactions are performed in the absence of solvent in relatively short reaction times in good to high yields. 相似文献
67.
In this article we introduce an ordinary differential equation associated to the one parameter family of Calabi–Yau varieties which is mirror dual to the universal family of smooth quintic three folds. It is satisfied by seven functions written in the q-expansion form and the Yukawa coupling turns out to be rational in these functions. We prove that these functions are algebraically independent over the field of complex numbers, and hence, the algebra generated by such functions can be interpreted as the theory of (quasi) modular forms attached to the one parameter family of Calabi–Yau varieties. Our result is a reformulation and realization of a problem of Griffiths around seventies on the existence of automorphic functions for the moduli of polarized Hodge structures. It is a generalization of the Ramanujan differential equation satisfied by three Eisenstein series. 相似文献
68.
Alireza Bananej Amir Hassanpour Hossein Razzaghi Mehdí Vaez zade Ali Mohammadi 《Optics & Laser Technology》2010,42(8):1187-1192
Monolayer ZrO2 and TiO2 films were prepared on BK7 glass by physical vapor deposition (PVD) and were subsequently annealed for 1 h at 300 °C. By using the transmission spectra of two samples and the envelope method, the refractive index dispersion and extinction coefficients have been calculated. Laser induced damage threshold (LIDT) measurement shows that despite slight differences between the extinction coefficients of the two samples, the LIDT parameter of the ZrO2 film is greater than that of the TiO2 film. This fact leads us to consider thermal conductivity as an important parameter for interpreting the LIDT difference. According to our theoretical analysis, as a consequence of increase in the number of thermal barriers along poorer film, its thermal conductivity, and hence LIDT, decreased, which is in agreement with our experimental results. The measured porosity of the two samples shows higher porosity for TiO2 single layer, which is in agreement with atomic force (AFM) images. The gradual and smooth damage morphology of ZrO2 observed in optical images implies higher thermal conductivity than TiO2. 相似文献
69.
The electrooxidation of Gabapentin was studied on nanotubes of nickel oxide-modified carbon paste electrode for the first time. Cyclic voltammetry was employed
to investigate the electrooxidation process. A simple, sensitive, and efficient amperometric method was developed for the
analysis of the drug, and the corresponding analytical parameters were reported. For Gabapentin, a detection limit of 0.3 μM
was obtained in a linear range of 2.4–50 μM. The proposed amperometric method was also applied to the analysis of commercial
capsules, and the results were in good agreement with the declared values. Also, the applicability of the method to the direct
assay of the drug in human serum and urine was described. 相似文献
70.
Mahdi Tohidian Mohadeseh Nouri Elham Jaafarnia Amir Hossein Haghighi 《Journal of Macromolecular Science: Physics》2015,54(1):17-31
The preparation and characterization of a new type of nanocomposite polyelectrolyte membrane, based on DuPont Nafion/imidazole-modified nanosilica (Im-Si), for direct methanol fuel cell applications is described. Related to the interactions between the protonated imidazole groups, grafted on the surface of nanosilica, and negatively charged sulfonic acid groups of Nafion, new electrostatic interactions can be formed in the interface of Nafion and Im-Si which result in both lower methanol permeability and also higher proton conductivity. Physical characteristics of these manufactured nanocomposite membranes were investigated by scanning electron microscopy, thermogravimetry analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy, water uptake, methanol permeability, and ion-exchange capacity, as well as proton conductivity. The Nafion/Im-Si membranes showed higher proton conductivity, lower methanol permeability and, as a consequence, higher selectivity parameter in comparison to the neat Nafion or Nafion/silica membranes. The obtained results indicated that the Nafion/Im-Si membranes could be utilized as promising polyelectrolyte membranes for direct methanol fuel cell applications. 相似文献