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441.
Maryam Salimi Elham Tavasoli Pouyan Moradifar Siamak Yassemi 《Algebras and Representation Theory》2014,17(4):1217-1234
This paper aims at generalizing the notions of “Auslander dual”, “k-torsionless” and “k-th syzygy” modules to the relative setting with respect to a semidualizing module. It is shown that the “relative” Auslander dual shares many nice properties with the Auslander dual originally introduced by Auslander and Bridger. It is also shown the interplay between the “relative” version of “k-torsionless” and “k-th syzygy” modules parallels that of k-torsionless and k-th syzygy modules. 相似文献
442.
Somayeh Behrouz Mohammad Navid Soltani Rad Saeid Rostami Marzieh Behrouz Elham Zarehnezhad Ali Zarehnezhad 《Molecular diversity》2014,18(4):797-808
The synthesis and biological effects of 15 novel azole-bonded \(\upbeta \) -hydroxypropyl oxime \(O\) -ethers have been described. In this synthesis, the oximation of aromatic ketones followed by an \(O\) -alkylation reaction with epichlorohydrin and/or epibromohydrin led to the corresponding \(O\) -oxime ether adducts. Subsequently, the attained \(O\) -oxime ether adducts were used to synthesize the target molecules after treating them with the appropriate azole derivatives. The in vitro antifungal and antibacterial activities of title compounds were obtained against several pathogenic fungi, Gram-positive and/or Gram-negative bacteria. Benzophenone \(O\) -2-hydroxy-3-(2-phenyl-1 \(H\) -imidazol-1-yl) propyl oxime and 9 \(H\) -fluoren-9-one \(O\) -2-hydroxy-3-(2-phenyl-1 \(H\) -imidazol-1-yl)propyl oxime proved to have considerable antifungal activity against Candida albicans, Candida krusei, Aspergillus niger, and Trichophyton rubrum. These two compounds demonstrated comparable antifungal activity to clotrimazole and fluconazole (standard drugs). All compounds were also tested against Escherichia coli and Staphylococcus aureus as Gram-negative and Gram-positive bacteria, respectively, and their activities were compared to gentamycin and ampicillin (reference drugs). In general, marginal antibacterial activity against tested bacteria was observed for the title compounds. A molecular docking study is also discussed for the two most potent compounds against fungi. The docking study reveals a considerable interaction between the two most potent compounds and the active site of Mycobacterium P450DM. Moreover, these two compounds are much strongly bound to the active site of Mycobacterium P450DM compared to fluconazole. 相似文献
443.
Investigation of Interfacial Charge Separation at PbS QDs/(001) TiO2 Nanosheets Heterojunction Solar Cell 下载免费PDF全文
Elham Ghadiri Bin Liu Jacques‐E. Moser Michael Grätzel Lioz Etgar 《Particle & Particle Systems Characterization》2015,32(4):483-488
In the recent years, the heterojunction solar cells based on quantum dots (QDs) have attracted attention due to strong light absorbing characteristics and the size effect on the bandgap tuning. This paper reports on the kinetics of interfacial charge separation of PbS QDs/(001) TiO2 nanosheets heterojunction solar cells. PbS QDs are deposited using a bifunctional linker molecule on two different TiO2 films, i.e., TiO2 nanosheets (with 001 dominant exposed facet) and TiO2 nanoparticles (with 101 dominant exposed facet). Upon bandgap excitation, electrons are transferred from the PbS QDs conduction band to the lower lying conduction band of TiO2. Based on the ultrafast pump‐probe laser spectroscopy technique, the kinetics of charge separation is scrutinized at the PbS/TiO2 interface. The interfacial charge separation at PbS/TiO2 nanosheets films made of (001) dominant exposed facets is five times faster than that on (101) dominant exposed facets TiO2 nanoparticles. The quantum yields for charge injection are higher for the (001) TiO2 nanosheets than the (101) TiO2 nanoparticles due to enhanced interfacial interaction with (001) surface compared to the (101) nanoparticles. The superior interfacial charge separation at PbS/(001) nanosheets respect to PbS/(101) nanoparticles is consistent with the higher photocurrent and enhanced power conversion efficiency in the PbS QDs/(001) TiO2 heterojunction solar cell. The use of (001) TiO2 nanosheets can be a better alternative to conventional mesoporous TiO2 films in QD heterojunction solar cells and perovskites‐based heterojunction solar cells. 相似文献
444.
Kazem D. Safa Elham Sharifi Shahin Tofangdarzadeh Akbar Hassanpour 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2433-2440
The reactions between a variety of functionalized alcohols and tris(dimethylsilyl)methane, (HMe2Si)3CH, are described. Alcohols such as ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, triethylene glycol monomethyl ether, 2-chloroethanol, 1-octanol, benzyl alcohol, glycidol, and allyl alcohol were converted in the presence of Karstedt's catalyst into the corresponding tris(alkoxydimethylsilyl)methanes, (ROMe2Si)3CH, in a convenient one-pot operation under aerobic conditions. The appearance of the products coincides with the generation of colloidal Pt(0) species. Moreover, poly(4-chloromethyl)styrene containing tris(dimethylsilyl)methyl groups reacts with benzyl alcohol or 2-chloroethanol in the presence of Karstedt's catalyst to give new macromolecules bearing tris(alkoxydimethylsilyl)methyl groups. The reaction rate is greatly influenced by the concentration of catalyst. 相似文献
445.
Ahmad Shaabani Elham Farhangi Abbas Rahmati 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):463-468
Silica-supported 1,1,3,3-tetramethylguanidine/Br2 complex is an efficient reagent for the selective oxidation of aliphatic and aromatic sulfides to the corresponding sulfoxides and the oxidative coupling of thiols to disulfides in aqueous solution at room temperature in a short reaction time. 相似文献
446.
A novel high-throughput device based on 96-micro-solid phase extraction (96-μ-SPE) system was constructed for multiresidue determination of nine pesticides in aquatic samples. The extraction procedure was performed on a commercially available 96-well plate system. The extraction module consisted of 96 pieces of 1 cm × 3 cm of cylindrically shaped stainless steel meshes. The prepared meshes were fixed in a home-made polytetrafluoroethylene-based constructed ninety-six holes block for possible simultaneous immersion of meshes into the center of individual wells. Dodecyl methacrylate and ethylene glycol dimethacrylate was copolymerized as a monolithic polymer and placed in the cylindrically shaped stainless steel meshes as extracting medium. A volume of 1 mL of the aquatic sample was transferred into the 96-well plate and the 96-μ-SPE device was applied for the extraction of the selected pesticides. Subsequently, the extracted analytes were analyzed by gas chromatography–mass spectrometry. Influential parameters such as polymer synthesis conditions, sorbent-to-sorbent reproducibility, ionic strength and extraction time were optimized. Intra and inter-sorbent reproducibility on 96-μ-SPE device were evaluated and results revealed that extraction yields are rather similar. Limits of detection were below 4 μg L−1 and the coefficient of determination was satisfactory (r2 > 0.99) for all the studied analytes. The developed method was successfully applied to the extraction and determination of the selected pesticides in surface water samples. 相似文献
447.
A simple and mild process for oxidation of xylenes to phthalic acids using N-hydroxyphthalimide/O2/HNO3 in an ionic liquid, wherein the ionic liquid can be successfully recovered and reused, is described. 相似文献
448.
Mohammad Hossein Habibi Elham Askari 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1345-1349
Nanocrystalline manganese-doped zinc oxide was synthesized by thermal decomposition of a zinc oxide sol with two new dinuclear manganese(III) complexes as precursor. Thermal analysis results indicated that the decomposition of manganese precursors occurred at 269 and 314 °C. X-ray structural analysis shows the presence of dimanganese core in the complexes and the binding of the ligands to the manganese(III) is through N2O2. The manganese-doped zinc oxide composite was characterized by means of X-ray diffraction, scanning electron microscopy, and UV–Vis spectroscopy. Structural properties of the composites elucidated that the manganese ions have substituted the zinc ions without changing the wurtzite structure of zinc oxide. 相似文献
449.
Saeed Nojavan Zeinab Tahmasebi Tina Bidarmanesh Hamideh Behdad Mahnaz Nasiri‐Aghdam Sozan Mansori Ahmad Pourahadi 《Journal of separation science》2013,36(19):3256-3263
An electromembrane extraction procedure coupled with HPLC and visible detection was applied for the extraction of three textile azo dyes as organic salts. The extraction parameters such as extraction time, applied voltage, pH range, and concentration of salt added were optimized. A driving force of 60 V was applied to extract the analytes through 2‐nitrophenyl octyl ether, used as the supported liquid membrane, into a neutral aqueous solution. This method required 20 min extraction time from a neutral sample solution. The proposed microextraction technique provided good linearity with correlation coefficients from 0.996 to 0.998 over a concentration range of 1.0–1000.0 ng/mL. The LODs of dyes were 0.30–0.75 ng/mL, while the reproducibility ranged from 6.7 to 12.9% (n = 6). Also, enrichment factors of 96–162 that corresponded to the recoveries ranging from 48 to 81% were achieved. Finally, the application of this new method was demonstrated on wastewater samples and some plants grown in contaminated environments. Excellent selectivity was obtained as no interfering peaks were detected. 相似文献
450.
Z. Tahmasebi Birgani Pamela Habibovic Lucas A. Kinard F. Kurtis Kasper Antonios G. Mikos John A. Jansen Sander C. G. Leeuwenburgh Jeroen J. J. P. van den Beucken 《Macromolecular bioscience》2013,13(6):777-788
The enzyme alkaline phosphatase (ALP) is added at different concentrations (i.e., 0, 2.5, and 10 mg · ml?1) to oligo(poly(ethylene glycol)fumarate) (OPF) hydrogels. The scaffolds are either incubated in 10 mM calcium glycerophosphate (Ca–GP) solution for 2 weeks or implanted in a rat subcutaneous model for 4 weeks. Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and alizarin red staining show a strong ability to form minerals exclusively in ALP‐containing hydrogels in vitro. Additionally, the calcium content increases with increasing ALP concentration. Similarly, only ALP‐containing hydrogels induce mineralization in vivo. Specifically, small (≈5–20 µm) mineral deposits are observed at the periphery of the hydrogels near the dermis/scaffold interface using Von Kossa and alizarin red staining.