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211.
Maasoumeh Jafarpour Abdolreza Rezaeifard Somayeh Gazkar Maryam Danehchin 《Transition Metal Chemistry》2011,36(7):685-690
Eight Schiff base compounds were prepared by condensation of 1-amino-2-propanol with different benzaldehydes in water. One
of the Schiff bases, (z)-N-bezylidene-2-hydroxypropane-1-amine (HL1), was used as a bidentate ligand for preparation of a zirconium complex (Zr(L1)2Cl2). The complex has been used as a catalyst for efficient synthesis of wide variety of indole derivatives in EtOH under mild
conditions. The turnover number and reusability of the catalyst indicate that it has high efficiency and is fairly stable
under the reaction conditions. 相似文献
212.
Alireza Salabat Rahmat Sadeghi Somayeh Tiani Moghadam Bahman Jamehbozorg 《The Journal of chemical thermodynamics》2011,43(10):1525-1529
The partitioning behavior of l-methionine has been studied in aqueous two-phase systems of (poly(propylene glycol) + sodium phosphate salts + H2O) at different temperatures. The salts used were sodium di-hydrogen phosphate (NaH2PO4), di-sodium hydrogen phosphate (Na2HPO4) and tri-sodium phosphate (Na3PO4). The effects of tie line length, salt type, and temperature on the partition coefficient of this amino acid have been studied. In addition, thermodynamic parameters (ΔH°, ΔS° and ΔG°) as a function of temperature were calculated. The results showed that increasing tie line length led to decreasing of the partition coefficient. We also showed that the partition coefficients of the amino acid in the systems containing Na3PO4 are greater than the other two salts. Moreover, it is verified that increasing temperature led to decreasing the partition coefficient. The experimental partition coefficient data are correlated using a modified virial-type model. 相似文献
213.
Somayeh Karimi Navid Mostoufi Rahmat Sotudeh-Gharebagh 《Journal of Optimization Theory and Applications》2014,160(3):1020-1026
The honey bee mating optimization (HBMO) algorithm is presented and tested with various test functions, and its performance is compared with the genetic algorithm (GA). It is shown that the HBMO algorithm can overcome the weaknesses of the GA. The HBMO converges faster than the GA. Even when the HMBO starts from a more improper initial condition than the GA, it can reach a better solution in a smaller number of function evaluations. Furthermore, in some cases, the GA was not able to reach the global minimum. 相似文献
214.
Akbar Mobinikhaledi Naser Foroughifar Somayeh Faghihi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1837-1842
Treatment of 2-aminopyridine ( 1 ) with chloroacetyl chloride in dry benzene gave 2-chloro-N-(pyridin-2-yl)acetamide ( 3 ), which on further reaction with potassium thiocyanate gave 2-imino-3-(pyridin-2-yl)thiazolidin-4-one ( 4 ) as an intermediate compound for the synthesis of pyridin-2-yl substituted 2-imino-thiazolidine-4-one derivatives. Cyclocondensation reaction of ( 4 ) with a series of aromatic aldehydes gave 5-arylidene derivatives of pyridin-2-yl substituted 2-imino-thiazolidine-4-ones 5a–j . 1 H and 13C NMR spectroscopy, as well as elemental analyses, were used for the identification of these new compounds. 相似文献
215.
Pirsaheb Meghdad Mohammadi Somayeh Khodarahmi Reza Hoseinkhani Zohreh Mansouri Kamran Payandeh Mehrdad 《Journal of fluorescence》2022,32(5):1733-1741
Journal of Fluorescence - In this research, DNA-modified carbon dots (CDs) were exploited to construct a fluorescence assay for breast cancer genes (BRCA1, a potential marker for cancer diagnosis)... 相似文献
216.
Fereydoon Laal Amir Hossein Khoshakhlagh Esmaeil Zarei Rohollah Fallah Madvari Somayeh Farhang Dehghan 《声与振动》2022,56(4):297-306
After controls, including engineering and management, the final way to control noise is to use hearing protection devices. Due to the lack of a standardized questionnaire regarding investigating workers’ use of hearing protection devices on the basis of the BASNEF behavioral model, the present study was conducted to investigate the effect of health education based on the BASNEF model on the use of hearing protection devices in workers of an automobile manufacturing plant in Iran. This quasi-experimental and prospective intervention study was performed on 80 workers at an automobile manufacturing plant who are exposed to noise levels above 85 decibels and do not use hearing protection devices. In this study, 40 people working in a cast iron foundry were selected as the intervention group, and 40 working in aluminum casting were chosen as the control group. Questionnaires were analyzed at the beginning of the intervention and three months after the intervention in the intervention and control groups. There was no significant difference between the intervention and control groups before the intervention. There was a significant difference between the intervention and control groups after the intervention in the area of knowledge. A significant correlation was observed between the intervention and control groups after the intervention program in all areas of the BASNEF educational model except behavioral intention. In this study, the effect of educational intervention on the use of hearing protection devices was investigated, and with the educational intervention, it was tried to get help from influential people and enabling factors in education based on the BASNEF model. The results showed that the educational intervention based on the BASNEF model can improve the knowledge of individuals in both the intervention and control groups. 相似文献
217.
Ultrashort laser-gas interaction is a promising candidate for the intense broad band far-infrared radiation in which the gas ionization and the resultant plasma formation occur consequently. The electron current produced in the process is the most important influential parameter which affects the far-infrared radiation generation. Although the interacting forces of the process are the space charge electric and the laser electromagnetic forces, the effect of the former one, has not been investigated on the gas-plasma THz generation. It is noteworthy that the space charge electric force, due to its effect on the electron distribution, has potential influence on the produced electron current and its consequent emission. Here, a 2D relativistic fluid model is presented in which the ions and the resultant space charge field are incorporated. The model investigates the air ionization, electron-ion plasma formation, and the system's evolution, spatiotemporally. Moreover, as the model is based on the transient electron current, as the source for the electromagnetic pulse radiation, it gives the temporal profile of the radiated field in which the space charge effects are observable. Our results show that the space charge field affects the electron velocity and its resultant current. Therefore, the temporal profiles and amplitudes of the radiated field components are affected and their resemblance to the experimental data is enhanced. The results indicate that the amplitude of the radiated field increases in the presence of the space charge field. In addition, it is shown that the space charge effects become more pronounced with the laser intensity. 相似文献
218.
Tahmineh Akbarzadeh Saeedeh Noushini Somayeh Taban Mohammad Mahdavi Mahsima Khoshneviszadeh Mina Saeedi Saeed Emami Mohammad Eghtedari Yaghoub Sarrafi Mehdi Khoshneviszadeh Maliheh Safavi Kouros Divsalar Mohammad Hassan Moshafi Ali Asadipour Reyhaneh Sabourian Najmeh Edraki Omidreza Firouzi Ramin Miri Abbas Shafiee Alireza Foroumadi 《Molecular diversity》2015,19(2):273-281
219.
Mohammad Navid Soltani Rad Somayeh Behrouz Abdo-Reza Nekoei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):465-476
Abstract A facile and efficient method for one-pot synthesis of N-alkyl sulfonamides from alcohols using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this protocol, treatment of various potassium sulfonylamide salts and alcohols in the presence of TsIm and triethylamine in refluxing DMF furnishes the corresponding N-alkyl sulfonamides in good to excellent yields. This methodology is highly efficient for reaction of various structurally diverse primary and secondary alcohols as well as potassium sulfonylamides. Also, the density functional theoretical calculations are employed to mechanistically study this protocol. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
220.
AbstractPoly(vinylidene fluoride)-based nanocomposite films with different loadings of PMMA-modified graphene sheets were prepared by a solution-mixing and solvent casting method. The prepared films were annealed at three different temperatures and the crystalline structures of the samples were investigated. X-ray diffraction data confirmed the PMMA-modified graphene nanosheets enhanced the preferential β-crystalline structure when increasing the annealing temperature to 90?°C, while increasing the annealing temperature to 120?°C led to a β → γ phase conversion. The tendency of the graphene sheets to restack by increasing the annealing temperature was confirmed by XRD. The PMMA-modified graphene sheets, however, didn’t showa nucleating effect on the PVDF crystallizationduring DSC cooling scans. 相似文献