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61.
Emad A. Jaffar Al-Mulla Nor Azowa Bt Ibrahim Kamyar Shameli Mansor Bin Ahmad Wan M. Zin Wan Yunus 《Research on Chemical Intermediates》2014,40(8):2887-2894
Hydrofluoric acid has been used as a stripping agent for molybdenum(VI) using a mixture of N,N’-carbonyl difatty amides (CDFAs) synthesized from palm oil as a extractant. The CDFAs was characterized by Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance technique. In the extraction step, the effects of parameters, such as type of diluent, hydrochloric acid, metal concentration, and temperature, have been studied. The effects of various stripping agents on stripping efficiency have also been investigated. This work presents the development of a low-cost and environmentally friendly extractant to recover molybdenum. 相似文献
62.
Khaled Osati Ali Salajegheh Mohammad Mahdavi Kamran Chapi Arash Malekian 《Isotopes in environmental and health studies》2014,50(2):169-183
Karst springs of the Zagros Mountains contribute a significant amount to agricultural and human water demands of western and south-western Iran. For an adequate management of available water resources in semi-arid and arid regions, sufficient hydrological monitoring is needed, and hydro-chemical and isotope hydrological data provide important additional information. About 350 water samples were collected from precipitation, river water, and karst springs of the upper part of the Karkheh River Basin (20,895 km2) located between 33°35′ and 34°55′ North and 46°22′ and 49°10′ East with elevations ranging from 928 to 3563 m above sea level. Sampling was conducted in monthly time resolution from August 2011 to July 2012. All samples were analysed for hydro-chemical parameters (pH, electrical conductivity, and major ions) and stable isotopes (deuterium, oxygen-18). Isotope values of precipitation indicate a local meteoric water line (Zagros MWL δ2H=6.8 δ18O+10.1; R2=0.99) situated between the Mediterranean MWL and Global MWL. Spring and river water isotope values vary between?7.1 and?4.1 ‰, and?38 and?25 ‰ for δ18O and δ2H, respectively, responding to winter snowmelt and evaporation. This work implements stable isotopes and hydro-chemical information of springs and river water to understand hydrological and hydro-geological interrelations in karstic semi-arid areas and helps to improve the current water resources management practices of western Iran. 相似文献
63.
Dr. Atash V. Gurbanov Dr. Maxim L. Kuznetsov Dr. Kamran T. Mahmudov Prof. Armando J. L. Pombeiro Prof. Giuseppe Resnati 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(65):14833-14837
Intramolecular chalcogen bonding in arylhydrazones of sulfamethizole is strengthened by conjugation in the π-system of a noncovalent five-membered ring. The S⋅⋅⋅O distance in the sulfamethizole moiety of these compounds ranges from 2.698(3) to 2.806(15) Å, which indicates its strong dependence on the attached arylhydrazone fragments. Information on the nature of the intramolecular chalcogen bond was afforded by DFT calculations. 相似文献
64.
An efficient one-pot synthetic methodology has been developed for the benzylic amination reactions of methyl-substituted azine N-oxides that operate under mild conditions. The reaction was found to tolerate quinoline and isoquinoline N-oxides with electron donating and withdrawing substituents as the electrophilic reaction partners as well as a broad range of nucleophilic primary, secondary and aromatic amines, affording the benzylic amination products in up to 82% yield. 相似文献
65.
Mostafaie A Bidmeshkipour A Shirvani Z Mansouri K Chalabi M 《Applied biochemistry and biotechnology》2008,144(2):123-131
Actinidin is a cysteine protease abundant in Kiwifruit. This enzyme is known as a meat-tenderizing protease. In this project,
actinidin was purified from kiwifruit by salt precipitation and ion exchange chromatography. Collagenolytic effect of the
purified enzyme was tested in four different buffer systems. Thereafter, the enzyme was used for isolation and culture of
cells from three different tissues: endothelial cells from human umbilical vein, hepatocytes from rat liver, and thymic epithelial
cells from rat thymus. Our results revealed that actinidin can hydrolyze collagen types I and II at neutral and alkaline buffers.
Furthermore, actinidin compared with type II or IV collagenase isolated intact human umbilical vein endothelial cells, hepatocytes,
and thymic epithelial cells with viability more than 90%. These results address a novel and valuable collagenase, which can
be used efficiently for hydrolysis of collagen and isolation of different cell populations from various solid tissues. 相似文献
66.
Prof. Dr. Skye Fortier José Veleta Dr. Amélie Pialat Jennifer Le Roy Kamran B. Ghiassi Prof. Dr. Marilyn M. Olmstead Dr. Alejandro Metta‐Magaña Prof. Dr. Muralee Murugesu Prof. Dr. Dino Villagrán 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):1931-1936
After more than 50 years, the synthesis and electronic structure of the first and only reported “U0 complex” [U(bipy)4] ( 1 ) has been reinvestigated. Additionally, its one‐electron reduced product [Na(THF)6][U(bipy)4] ( 2 ) has been newly discovered. High resolution crystallographic analyses combined with magnetic and computational data show that 1 and its derivative 2 are best described as highly reduced species containing mid‐to‐high‐valent uranium ligated by redox non‐innocent ligands. 相似文献
67.
A new copper(II) complex, [Cu(Bphen)(Leu)(NO3)(H2O)] (Bphen = 4,7-diphenyl-1,10-phenanthroline, leu = L-leucine), has been synthesized and characterized by IR spectroscopy, CHN analysis, and single-crystal X-ray diffraction techniques. The CT-DNA binding properties of the complex have been investigated by both absorption and emission spectroscopy. The binding parameters for the fluorescence Scatchard plot were also determined. Further, the interaction of the complex with bovine serum albumin (BSA) has been investigated using absorption and emission spectroscopy. The thermodynamic parameters, free energy change (ΔG), enthalpy change (ΔH), and entropy change (ΔS), were calculated by the van’t Hoff equation and discussed. The distance between BSA and the complex has been obtained according to fluorescence resonance energy transfer. Conformational changes of BSA have been observed from synchronous fluorescence. Antioxidant and radical scavenging activities of the complex were determined by various in vitro assays such as 1,1-diphenyl-2-picryl-hydrazyl free radicals (DPPH˙), 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radicals (ABTS˙+), and reducing ability determination by H2O2 scavenging methods. 相似文献
68.
69.
70.
Kamran Akhbari 《Journal of organometallic chemistry》2007,692(23):5109-5112
In the solid state, the Tl(I) complex of 4-hydroxybenzoate (HB−), [Tl(HB)]n (1), can be regarded as containing polymeric chains linked through 2 × η6 interactions of the Tl atoms with phenyl groups from adjacent units. The thallium atoms contain close TlI ? π (aromatic) contacts, thus attaining a total hapticity of 16 with environments TlO4C12. The unusually high coordination number in the this compound may reflect the capacity of Tl(I) to act as both a Lewis acid and a Lewis base. 相似文献