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111.
The magnetic filtration theory was evaluated to intensify the filtration of industrial fluids by magnetic filters. Effects of filtration velocity and external magnetic field intensity on filter performance were investigated and the dependence of the logarithmic efficiency coefficient on filtration velocity was questioned. It was concluded that change in the magnetic susceptibility of the dispersion particles, caused by external magnetic field, and change in the flow rate properties of the liquid alongside the filter pores are the most essential factors to be considered in the design, development, and modeling of magnetic filtration systems in various industrial areas. 相似文献
112.
Gürsoy Süleyman Koçak Makbule Cihan Ali Gül Ahmet Bekaroğlu Özer 《Transition Metal Chemistry》2000,25(4):474-477
A new soluble vic-dioxime ligand namely 1,4-bis(2′-hydroxyethyl)-2,3-bis(hydroxyimino)-5,6-diphenylpiperazine, (LH2) containing optically active centers has been prepared as a mixture of isomers from (CNO)2 and N,N-bis(2-hydroxyethyl)stilbendiamine (1) which has been made by the reduction of the condensation of the product of benzaldehyde and 2-aminoethanol in the presence
of aluminum amalgam. N,N-coordinated planar metal complexes of this ligand have been synthesized with NiII, CuII, CoII, PdII and UVIO2. Oxidation of (LH)2Co in the presence of a base, such as pyridine, leads to an octahedral complex (LH)2CopyCl containing pyridine and chloride as axial ligands in addition to vic-dioxime ligands. The structures of the ligand and its complexes are proposed on the basis of elemental analysis, 1H-n.m.r., mass, i.r. and u.v.–vis. spectral data.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
113.
Zeynep Kalaycıoğlu 《Journal of separation science》2023,46(22):2300391
Histamine is a biogenic amine found in various body tissues and responsible for many critical vital activities. It is also responsible for allergic reactions in the body. Ingestion of foods containing high amounts of histamine can cause fatal allergic reactions. Albumin in plasma controls drugs and free concentrations of bioactive constituents taken to the body with food. Hence, this study aimed to characterise the interactions of histamine with bovine serum albumin. Capillary electrophoresis in the frontal analysis mode was employed in this study as a practical approach for assessing histamine-bovine serum albumin affinity. The plateau-shaped free histamine peak was well separated from the bovine serum albumin (BSA)-histamine complex peak. The free histamine concentration was obtained by following the height of the free histamine peak. Whereas the bound histamine concentrations were obtained by calculating the difference between the height of total and free histamine peaks. Histamine bound to BSA at one independent site with a Kb value of 2.50 × 103 L/mol. Moreover, an in-silico molecular docking method was performed, and it was revealed that the binding site of histamine was located closer to Lysine-131 in subdomain IIA of bovine serum albumin. 相似文献
114.
早在六十年代,人们为了寻找较好的激光玻璃,曾对Sm~(3 )离子掺杂的玻璃中的光谱进行过研究。为了探寻新型的激光,发光玻璃,又进一步研究了Sm~(3 )在玻璃中的发光和敏化。我们以寻找一种高亮度,低成本的发光玻璃为目的,研究了基质玻璃组成,敏化离子及其浓度对Sm~(3 )发光性质的影响。 选择B_2O_3-BaO-M_mO_n(M_mO_n=Li_2O,Na_2O,K_2O,MgO,CaO,SrO)玻璃体系,所用原料的纯度皆为分析纯以上,用陶瓷坩埚在1250℃掺杂氧化钐(纯度均大于99%),玻璃的荧光谱和激发光谱,用MPF-4型荧光分光光度计测定。 相似文献
115.
Avcıbaşı Uğur Türkyarar Taner Karadağ Ayşegül Bakan Buket Yavaşoğlu Nefise Ülkü Karabay Kuşat Kevser Akgöl Sinan Gülcemal Derya Tekin Volkan Müftüler Fazilet Zümrüt Biber Topal Gökcen Parlak Yasemin Gümüşer Fikriye Gül 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):511-525
Journal of Radioanalytical and Nuclear Chemistry - The aim of this study is the synthesis of a novel 99mTc-labeld graft polymer and the biological evaluation of its in vitro and in vivo properties.... 相似文献
116.
Microstructure of nickel nanoparticles embedded in carbon films: case study on annealing effect by micromorphology analysis 下载免费PDF全文
Ştefan Ţălu Miroslaw Bramowicz Slawomir Kulesza Azizollah Shafiekhani Maryam Rahmati Atefeh Ghaderi Mohammad Ahmadirad Shahram Solaymani 《Surface and interface analysis : SIA》2017,49(3):153-160
The presented study is aimed at analyzing the surface texture of amorphous hydrogenated carbon layers containing nickel nanoparticles (Ni‐NPs@a‐C:H) within their structure, which were deposited by Radio Frequency (RF) sputtering and RF‐Plasma Enhanced Chemical Vapor Deposition (RF‐PECVD) methods on glass substrates. Prepared films were then used as research material following their annealing at two different temperatures of 250 °C and 350 °C in an inert argon atmosphere. Series of height samples were taken with the help of atomic force microscopy (AFM) operating in a non‐contact mode and examined in order to determine their fractal characteristics. Raw AFM data were first plane‐fitted to remove the surface bow exhibiting the so‐called residual surface, and then numerically processed to calculate the Areal Autocorrelation Function (AACF), which was later used to compute the Structure Function (SF). The log–log plots of the latter served for calculation of fractal properties of surfaces under investigation, including fractal dimension D, and pseudo‐topothesy K. The analysis of 3‐D surface texture helps to understand their essential characteristics and their implications as well as graphical models and their implementation in computer simulation. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
117.
Nuran Kahriman Serhat Gün Abidin Gümrüküolu Nurettin Yayl Ümmühan Ocak Mira Ocak 《Journal of heterocyclic chemistry》2019,56(9):2612-2618
Anion sensor properties of N‐alkyl‐substituted 1,4′‐diazaflavonium bromides in methanol–water were evaluated by UV–vis spectrometry. Pronounced changes were observed in the absorption spectra of all compounds for only OH?, CO32?, and CN? among F?, Cl?, Br?, I?, OH?, CO32?, NO3?, PO43?, CN?, SO42?, HSO4?, HCO3?, SCN?, NO2?, and P2O72? ions. Two new absorption bands at 385 and 685 nm accompanying the distinct color change for OH?, CO32?, and CN? ions were observed in case of all compounds. The color changes were from pink to blue for CO32? and OH? ions and from pink to purple for CN? ion. Thanks to the distinct color change, the compounds can be used as selective colorimetric anion sensors. Linear changes of absorbance of N‐heptyl‐substituted compound at 385 nm as a function of the ion concentration were used to determine CN? ion in water samples. Detection and quantification limits of the proposed method were 0.94 and 2.82 mg/L, respectively. 相似文献
118.
Activated carbon production from almond shells using phosphoric acid activation agent was achieved by applying both conventional heating and microwave heating in succession. The morphology and surface properties of activated carbon were studied using thermogravimetric and differential gravimetric analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy, and Brunauer–Emmett–Teller analysis. A surface area of 1128 m2/g was achieved by optimizing the microwave power (500?W), microwave application time (15?minutes), conventional heating time (45?minutes), conventional heating temperature (500?°C), and the phosphoric acid:sample ratio (0.7:1). An adsorption capacity of methylene blue of 148?mg/g and an iodine value of 791?mg/g was obtained for the prepared activated carbon. 相似文献
119.
Firstly, poly[phenyl thiadiazole methacrylamide-co-divinylbenzene-co-2-acrylamido-2-methylpropane sulfonic acid] (PTMAAm-co-DVB-co-AMPS), a new polymer resin was synthesized. This polymer resin was characterized by elemental analyzer, X-ray diffractometer, scanning electron microscope (SEM) and IR spectrometer. The glass column packed with the synthesized polymer resin was used for solid phase extraction (SPE). At the same time, the analytes were separated and preconcentrated from various water, dried vegetables samples and standard reference material (CRM) with SPE and determined by flame atomic absorption spectrometer (FAAS). The experimental conditions of this method such as pH, flow rates of sample, flow rates of eluent, type / concentration / volume of eluent, sample volume and matrix ions were examined. The limits of detection (µg L?1) were calculated (3s) 0.9 for Mn(II), 1.4 for Cd(II), Co(II) and Zn(II), 1.5 for Cr(III), 2.2. for Cu(II), 1.9 for Pb(II),1.5 for Ni(II) and 1.9 for Fe(III) (n = 21). The low relative standard deviation, ≤ 2% (n = 11) and preconcentration factor as 75 for analytes were obtained. 相似文献
120.
Herein we report, a series of new benzimidazolium chlorides as N-heterocyclic carbene (NHC) ligand and their corresponding palladium(II)-NHC complexes with the general formula [PdCl2(NHC)2] were synthesized. All new compounds were characterized by 1H NMR, 13C NMR, IR spectroscopy and elemental analysis techniques. The catalytic activity of palladium(II)-NHC complexes was investigated in the direct C2- or C5-arylation of thiazoles with aryl bromides in presence of palladium(II)-NHC at 150?°C for 1?h. These complexes exhibited the good catalytic performance for the direct arylation of thiazoles. The arylation of thiazoles regioselectively produced C2- or C5-arylated thiazoles in moderate to high yields. 相似文献