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101.
Milad Javanmard Hossein Ali Asadi-Gharneh Pejman Nikneshan 《Natural product research》2018,32(14):1738-1743
Dog rose (Rosa canina L.) is a wild native species in Iran, with a significant genetic diversity. This plant serves as a rich source of vitamin C, anthocyanins, phenolic contents and carotenoids. Rose hips have been used in several food products, as well as perfumery and cosmetics industries. In this research, we investigate biochemical characteristics of five dog rose ecotypes (Kopehjamshid, Zarneh, Miyankish, Aghcheh and Sadeghiyeh), that were collected from the central part of Iran (Isfahan province). Amounts of vitamin C, total carotenoids, total phenolic contents, total anthocyanins, macro and micro minerals were measured. Seed oil are extracted by soxhlet method and analysed by gas chromatography. The macro and micro minerals levels in the fruit vary significantly among these regions. The results of this study demonstrate that dog rose have great diversity and can be used in breeding programmes in order to increase nutrient values as a food resource additive. 相似文献
102.
Behzad Rezaei Maryam Mokhtarianpour Ali Asghar Ensafi 《Journal of the Iranian Chemical Society》2018,15(4):955-965
In this work, a 304 stainless steel (SS) was anodized to prepare nanoporous SS (NPSS) with an average size of about 75 nm and then filled with copper (Cu/NPSS) using pulsed electrodeposition method. Afterward, a nanostructural Pt and Pd film was deposited by galvanic replacement (GR) on the Cu/NPSS to prepare modified electrode (PtPd/Cu/NPSS) for hydrogen evolution reaction (HER) and formic acid electrooxidation (FAO). The electrocatalytic activity of the modified electrode and its structural characterization have been studied by voltammetric methods, electrochemical impedance spectroscopy (EIS), inductively coupled plasma optical emission spectrometry (ICP-OES), and field emission scanning electron microscopy (FESEM). The results show that the nanostructural Pt1Pd1/Cu/NPSS composition, with low Pt loading and suitable stability, has a good electrocatalytic performance toward HER (EOnset = + 12 mV vs. NHE) and FAO (EOnset = ?180 mV vs. NHE). For HER observed a high mass activity of noble metals (87.54 mA cm?2μg Pd+Pt ?1 ) in comparison with Pt deposited Cu/NPSS (41.5 mA cm?2 μg Pt ?1 ) at the same applied potential of ? 0.25 V versus NHE. Also, the fabricated electrocatalysts with more electrochemically active surface area in comparison with Pd/Cu/NPSS and Pt/Cu/NPSS revealed more resisting to the poisoning components and good stability for FAO. 相似文献
103.
Pejman Abdollahzadeh Karegar 《Wireless Networks》2018,24(8):2825-2833
According to rapid extension of wireless sensor network localization, indoor localization using fingerprint has turned out to be more considerable lately. It contains of a database called Receive Strength Signal Indicator vectors, which is a primitive amount in wireless sensor network fingerprinting positioning. The equivalence of a few strategies is brought up from the literary works, and some new variants are presented in this study. A combination of a clustering strategy named affinity propagation and statistical and probabilistic positioning procedures is considered in this review and at the same time, the impact of some components in our methodology onto positioning precision will be investigated. Affinity propagation clustering method set up a common baseline for assessing the relative accuracy of various indoor location methods effectively. Eventually two coarse localization methods as Mahalanobis norm method and similarity to exemplar receive strength signal vector are compared based on positioning accuracy and performance. Experimental outcomes prove that the intended algorithm will advance the accuracy and localization error compared with the method without clustering. 相似文献
104.
One of the main electrochemical characteristics of a lead-acid battery is amount of water consumption. The effect of solidification temperature on electrochemical behavior (mainly hydrogen overvoltage) of Pb–Ca–Sn–Al (0.09%, Ca; 0.9%, Sn; 0.02%, Al) and Pb–Sb–Sn (1.7%, Sb; 0.24%, Sn) alloys, which are used in making the grid of lead-acid batteries, has been studied by cyclic voltammetry (CV) and linear sweep voltammety for different concentrations of sulfuric acid (ranging from 0.5 mol L–1 to 4.0 mol L–1). The morphology of the grid at some solidification temperatures was studied by optical microscopy. After one sweep of CV the surface of the electrode was investigated by using scanning electron microscopy.The results show that the potential of hydrogen evolution depends on the solidification temperature of the grids during production (mold temperature of grid casting). Also, at different solidification temperatures, different passivation phenomena, electrode surface constituents, and structure were observed. 相似文献
105.
The thermodynamic parameters underlying the binding of Mg2+ to the hydrophobic core of human growth hormone, hGH, are determined using isothermal titration calorimetry. The interaction
between Mg2+ and hGH (35 μM) was studied at 27°C in NaCl solution. A new solvation model was used to reproduce the enthalpies of Mg2+-hGH interaction over the whole Mg2+ concentrations. The solvation parameters recovered from the new salvation model, were correlated to the structural changes
of hGH due to the metal ion interaction. 相似文献
106.
Pt(II) complexes immobilized on polymer‐modified magnetic carbon nanotubes as a new platinum drug delivery system 下载免费PDF全文
Seyed Jamal Tabatabaei Rezaei Ali Hesami Hossein Khorramabadi Vahid Amani Asemeh Mashhadi Malekzadeh Ali Ramazani Hassan Niknejad 《应用有机金属化学》2018,32(7)
We combine nanotechnology and chemical synthesis to create a novel multifunctional platinum drug delivery vehicle based on magnetic carbon nanotubes (multiwall carbon nanotubes/Fe3O4@poly(citric acid)/cis‐[(Pt(1,7‐phenanthroline)(DMSO)Cl2)]‐b‐poly(ethylene glycol) (MCNTs/FO@PC/Pt(II)‐b‐PEG)) for targeted cancer therapy. MCNTs/FO@PC/Pt(II)‐b‐PEG was conveniently prepared by conjugating cis‐[Pt(1,7‐phenanthroline)(DMSO)Cl2] complex to MCNTs/FO@PC‐b‐PEG via strong hydrogen‐bonding interactions. In comparison with free cisplatin and Pt(II) complex, MCNTs/FO@PC/Pt(II)‐b‐PEG shows higher solubility in aqueous solution and higher cytotoxicity towards human cervical cancer HeLa cells and human breast cancer MDA‐MB‐231 cells. In vitro release experiments revealed that the platinum drug‐loaded delivery system is relatively stable under physiological conditions (pH = 7.4 and 37 °C) but susceptible to acidic environments (pH = 5.6 and 37 °C) which would trigger the release of loaded drugs. Fluorescence microscopy studies revealed that this magnetic nanohybrid system possesses marked cell‐specific targeting in vitro in the presence of an external magnetic field. The results indicated that the prepared superparamagnetic MCNTs/FO@PC/Pt(II)‐b‐PEG nanohybrid system is a promising candidate for inhibiting the proliferation of cancer cells. 相似文献
107.
G. Rezaei Behbehani A. A. Saboury A. Fallah Baghery 《Journal of solution chemistry》2007,36(10):1311-1320
The interaction of myelin basic protein (MBP) from the bovine central nervous system with divalent calcium ion was studied
by isothermal titration calorimetry at 27 °C in aqueous solution. The extended solvation model was used to reproduce the enthalpies
of Ca2+-MBP interaction over the whole range of Ca2+ concentrations. The solvation parameters recovered from the solvation model were attributed to the structural change of MBP
due to the metal ion interaction. It was found that there is a set of two identical and non-interacting binding sites for
Ca2+ ions. The association equilibrium constant is 0.021 μmol⋅dm−3. The molar enthalpy of binding is ΔH=−15.10 kJ⋅mol−1. 相似文献
108.
Rezaei M McKellar AR Moazzen-Ahmadi N 《The journal of physical chemistry. A》2011,115(38):10416-10422
Infrared spectra of the C(2)H(2)-(OCS)(2) trimer are studied by means of direct infrared absorption spectroscopy. The van der Waals complexes are generated in a supersonic slit-jet apparatus and probed using a rapid-scan tunable diode laser in the region of the ν(1) fundamental vibration of the OCS monomer. Two infrared bands are analyzed for the lowest energy isomer of the trimer, which has C(2) symmetry and is experimentally observed here for the first time. A relatively strong band centered at 2068.93 cm(-1) is assigned as the out-of-phase vibrations of the pair of equivalent OCS monomers. This band is blue-shifted relative to the free OCS monomer but with a reduced shift as compared with the analogous vibration of the nonpolar OCS dimer. A weaker red-shifted band observed at 2049.64 cm(-1) establishes the nonplanarity of the OCS dimer subunit within the trimer. Spectra for three isotopologues in addition to the normal form are used to help define an experimental structure, which agrees well with past and present semiempirical calculations. 相似文献
109.
Rezaei Shokoofe Rahpeima Soraya Esmaili Javad Javanbakht Vahid 《Russian Journal of Applied Chemistry》2021,94(4):533-548
Russian Journal of Applied Chemistry - Magnetic nanoparticles and clay minerals combine to form a class of advanced nanocomposites that would possess exceptional adsorption, magnetism, and... 相似文献
110.