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71.
72.
Seyed Naser Azizi Mohammad Javad Chaichi Parmis Shakeri Ahmadreza Bekhradnia 《Journal of fluorescence》2013,23(2):227-235
In this article, a novel chemiluminescence method using water-soluble CdS quantum dots (QDs) as sensitizers is proposed for the chemiluminometric determination of epinephrine. The method is based on the quenching effect of epinephrine on the chemiluminescence emission generated by the mixing of CdS quantum dots (QDs) with hydrogen carbonate (HCO3 -) in the presence of hydrogen peroxide (H2O2) in an alkaline medium. The optimization of variables influencing the chemiluminescence response of the method has been carried out by using experimental design. Under the optimal conditions, there is good linear relationship between the relative chemiluminescence intensity and the concentration of epinephrine over the range of 5?×?10?9–1?×?10?6?molL?1 with a 3σ detection limit of 5?×?10?11?molL?1. The method has been successfully applied to the determination of epinephrine in pharmaceutical formulation and the recovery test was done in human urine. 相似文献
73.
Kazem?KaramiEmail author Corrado?Rizzoli Naser?Rahimi 《Transition Metal Chemistry》2011,36(8):841-846
Reaction of the dinuclear complex [Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4}Cl]2 (1) with ligands (L = 4-picoline, sym-collidine) gave the six-membered palladacycles [Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4}Cl(L)] (2). The complex 1 reacted with AgX (X = CF3SO3, BF4) and bidentate ligands [L–L = phen (phenanthroline), dppe (bis(diphenylphosphino)ethane), bipy(2,2′-bipyridine) and dppp
(bis(diphenylphosphino)propane)] giving the mononuclear orthopalladated complexes [Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4}(L–L)] (3) [L–L = phen, dppe, bipy and dppp]. These compounds were characterized by physico-chemical methods, and the structure of
[Pd{κ2-N2′,C1-2-(2′-NH2C6H4)C6H4}Cl(L)] (L = sym-collidine) was determined by single-crystal X-ray analysis. 相似文献
74.
Akbar J Tavakoli N Marangoni DG Wettig SD 《Journal of colloid and interface science》2012,377(1):237-243
An evaluation of the physical interactions between gemini surfactants, DNA, and 1,2-dialkyl-sn-glycero-3-phosphoethanolamine helper lipid is presented in this work. Complexation between gemini surfactants and DNA was first investigated using surface tensiometry where the surface tension profiles obtained were found to be consistent with those typically observed for mixed surfactant-polymer systems; that is, there is a synergistic lowering of the surface tension, followed by a first (CAC) and second (CMC) break point in the plot. The surfactant alkyl tail length was observed to exhibit a significant effect on the CAC, thus demonstrating the importance of hydrophobic interactions during complexation between gemini surfactants and DNA. The second study presented is an investigation of the mixing interactions between gemini surfactants and DOPE using Clint's, Rubingh's, and Motomura's theories for mixed micellar formation. The mixing interactions between the 16-3-16/16-7-16/16-12-16/16-7NH-16 gemini surfactants and DOPE were observed to be antagonistic, where the strength of antagonism was found to be dependent upon the gemini surfactant spacer group and the solution composition. 相似文献
75.
Hosseini M Shafei MN Safari V Taiarani Z Kafami Ladani M Sadeghian R 《Natural product research》2012,26(16):1544-1548
The effect of olibanum administered during lactation to methimazole-treated dams on the learning of offspring was evaluated. The animals were treated for 60 days from the first day of lactation period: group 1--tap water, group 2-0.03% methimazole and groups 3 and 4-0.03% methimazole with 0.25% or 0.125% olibanum, respectively. The serum thyroxin level in the offspring of group 2 was significantly lower than that of group 1. However, there was no difference compared to groups 3 and 4. In a Morris water maze, the distance and time latency to reach the platform in offspring of group 2 was significantly higher than groups 1, 3 and 4. In probe trial, the time spent in target quadrant (Q?) by offspring of group 2 was lower than groups 1,?3 and 4. It is suggested that impaired learning and memory in the offspring of hypothyroid rats may be prevented by olibanum. 相似文献
76.
Naser Zare Dehnavi Mohsen Fathi Farhad Tavakoli 《International Journal of Theoretical Physics》2013,52(11):3886-3891
The observational data indicate that about 70 % of the total energy density of the current state universe has been occupied by Dark Energy. This is said to be the cause of the accelerated expansion of universe. In this letter we shall use a curvature constant as a scalar field in the quintessence Dark Energy model, for an isotropic universe. Connected to the so-called model, we will specify a definite dynamical field equation from the initial action of the theory. 相似文献
77.
78.
The expression of biosynthesis controlling genes of crocin and safranal in saffron (Crocus sativus) can be influenced by ultrasonic waves. Sterilized saffron corms were cultured in a ½-MS medium supplemented by 2-4-D and BAP. Saffron callus cells were treated with ultrasonic waves in a cellular suspension culture under optimal growth conditions. The samples were collected at 24 and 72 hours after treatment in three replications. The secondary metabolites were measured by high-performance liquid chromatography and the gene expression was analysed by the real-time polymerase chain reaction. Results indicate that this elicitor can influence the expressions of genes CsBCH, CsLYC and CsGT-2; the ultrasonic waves acted as an effective mechanical stimulus to the suspension cultures. The analysis of variance of the ultrasonically produced amounts of safranal and crocin indicates that there is a significant difference between once- and twice-treated samples in that the amount of safranal was the highest within the samples taken from the twice-treated suspension culture at 72 h after the ultrasound treatment, and the crocin was maximised after 24 h passed the twice-applied ultrasound treatment. 相似文献
79.
The catalytic activity of l ‐arginine‐coated nano‐Fe3O4 particles (Fe3O4@l ‐arginine) proves they are a novel magnetic catalyst without the use of heat and reflux for the synthesis of 1,3‐diaryl‐2‐N‐azaphenalene derivatives and n‐acyl‐1,3‐diaryl‐2‐N‐azaphenylene derivatives in a one‐pot pseudo‐five‐component condensation reaction of compounds of 2,7‐naphthalene diol, aldehydes, and ammonia derivatives (ammonium acetate or ammonium hydrogen phosphate) and solvent (water and alcohol) with high yield and short reaction times, economical, and simple workup. The structure and magnetic properties of the obtained nanoparticles were characterized via Fourier transform infrared spectroscopy (IR) and field emission scanning electron microscopy (FE‐SEM). The results demonstrated that the average size of the synthesized magnetite nanoparticles is about 21 nm. In addition, the heterogeneous catalyst can be easily recovered magnetically and can be reused for further runs without significant loss of its catalytic activity. 相似文献
80.
Tasviri Mahboubeh Miri Naser Mohaghegh Neda 《Research on Chemical Intermediates》2019,45(3):1039-1055
Research on Chemical Intermediates - A deposition method was applied to synthesize a multicomponent photocatalyst based on apatite (HaP)-coated Ag/AgBr/Bi2WO6 (denoted as HaP/Ag/AgBr/Bi2WO6).... 相似文献