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11.
A novel membrane sensor for selective monitoring of iodide, consisting of a triiodide‐ketoconazole ion pair complex dispersed in a PVC matrix, plasticized with a mixture of 2‐nitrophenyl octyl ether and dioctylphtalate with unique selectivity toward iodide ions, is described. The influence of membrane composition, pH of test solution and foreign ions on the electrode performance were investigated. The optimized membrane demonstrates a near‐Nernstian response for iodide ions over a wide linear range from 1.0 × 10?2 to 1.0 × 10?5 M, at 25 ± 1 °C. The electrode could be used over a wide pH range 3–10 and has the advantages of high selectivity, fast response time and good lifetime (over 4 months). It was successfully used as indicator electrode in potentiometric titrations and direct potentiometric assay of iodide ions. 相似文献
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Masoud Behzad Karel Samec Sang-In Bak Yacine Kadi Claudio Tenreiro Seung-Woo Hong Jong-Seo Chai 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(2):1001-1006
A worldwide challenge in the near future will be to find a way of producing radioisotopes in sufficient quantity without relying on research reactors. The motivation for this innovative work on targets lies in the accelerator-based production of radioisotopes using a neutron converter target as in the transmutation by adiabatic resonance crossing concept. Thermal analysis of a multi-channel helium cooled device is performed with the computational fluid dynamics code CFX. Different boundary conditions are taken into account in the simulation process and many important parameters such as maximum allowable solid target temperature as well as uniform inlet velocity and outlet pressure changes in the channels are investigated. The results confirm that the cooling configuration works well; hence such a solid target could be operated safely and may be considered for a prototype target. 相似文献
14.
There has been a considerable interest in recent years in developing polymer gel matrices for many important applications such as 2DE for quantization and separation of a variety of proteins and drug delivery system to control the release of active agents. However, a well‐defined knowledge of the ultrastructures of the gels has been elusive. In this study, we report the characterization of two different polymers used in 2DE: Gelatin, a naturally occurring polymer derived from collagen (protein) and agar, a polymer of polysaccharide (sugar) origin. Low‐temperature SEM is used to examine the internal structure of these gels in their frozen natural hydrated states. Results of this study show that both polymers have an array of hollow cells that resembles honeycomb structures. While agar pores are almost circular, the corresponding Gaussian curve is very broad exhibiting a range of radii from nearly 370 to 700 nm. Gelatin pores are smaller and more homogeneous reflecting a narrower distribution from nearly 320 to 650 nm. Overall, these ultrastructural findings could be used to correlate with functions of the polymers. 相似文献
15.
Nader Mansoori Oghaz Behzad Haghighi Mohammad Mehdi Alavianmehr Ebrahim Ghiamati 《Journal of solution chemistry》2013,42(3):544-554
A robust and efficient procedure is presented for calculating the solubility parameter. An analytical equation for internal pressure is proposed. Through a simple relation reported by Verdier and Andersen (fluid phase equilibrium 231: 125–137, 2005), one can easily find the solubility parameter via our analytical equation for the internal pressure. Also, the radial distribution function (RDF) of a Lennard–Jones LJ (12, 6) fluid, proposed by Xu and Hu (fluid phase equilibrium 30: 221–228, 1986), has been employed to calculate the internal pressure of normal alkanes from methane to decane. Their solubility parameters were evaluated according to the calculated values of the internal pressure. A comparison between the experimental and the estimated values demonstrated a very good agreement between them. 相似文献
16.
Hormoz Eslami Soleyman Hosseinzadeh Younes Saadat Faramarz Afshar-Taromi Mehdi Rimaz 《Colloid and polymer science》2012,290(14):1463-1469
In this work, the preparation of micron-sized polymer particles with nonspherical shapes via seeded dispersion polymerization of 2-ethylhexyl methacrylate (EHMA) with polystyrene (PS) seed particles in the presence of decane droplets and evaporation of decane after the polymerization under various polymerization conditions was discussed. The effect of monomer and decane content and polarity of the medium on the shape of the obtained particles was investigated. The experimental results showed that decreasing the amount of monomer and hydrocarbon volume of PEHMA/hydrocarbon domains, the particles decreased but they grew symmetrically, resulting in symmetric shapes. Furthermore, it was suggested that because of changing the solubility of the oligoradicals and hydrocarbon in the medium, the shape of the particles changed with changing the polarity of the medium. With decreasing the polarity of the medium, solubility of the oligoradicals in the medium increases and bigger polymer domains form on the surface of PS particles which can absorb higher amounts of decane. All of these can contribute to an increase in volume reduction after extraction of PEHMA/decane, resulting in various particle shapes. Further decreasing in polarity of the medium leads to an increase in the solubility of decane in the medium and decreasing the absorbed amount of decane by PS particles and PEHMA domains, resulting in lower volume reduction after evaporation of decane. 相似文献
17.
Zahra Taji Ali A. Ensafi Elahe Heydari-Soureshjani Behzad Rezaei 《Electroanalysis》2021,33(2):304-313
In this work, a modified 3D-rGO/MWCNT with nickel and copper oxide nanoparticles were synthesized. The structural properties of this nanocomposite were investigated by several techniques. The fabricated sensor at optimum condition potential of +0.60 V (vs. Ag/AgCl) and a rotational rate of 1800 rpm gave a detection limit of 0.04 μmol L−1 with two dynamic ranges of 0.10–300 and 300–900 μmol L−1 glucose with high stability. The good accuracy of the fabricated sensor was proved in the determination of glucose in a blood sample (with recoveries between 95 % to 105 % and RSDs of 1.2 to 2.5 %). 相似文献
18.
S. Hossein-Zadeh A. Iranmanesh M. A. Hosseinzadeh A. Hamzeh M. Tavakoli A. R. Ashrafi 《Journal of Applied Mathematics and Computing》2017,54(1-2):69-80
In this paper we present explicit formulas for computing the topological efficiency index of the most important graph operations such as the Cartesian product, composition, corona, join and hierarchical product of two graphs. We apply our results to compute this distance-related invariant for some important classes of molecular graphs and nano-structures by specializing components of these graph operations. 相似文献
19.
Research on Chemical Intermediates - An efficient ecofriendly approach has been developed for one-pot multicomponent synthesis of fused polycyclic dihydropyridine (DHP) derivatives. Tandem... 相似文献
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