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81.
The adsorption of Cu(II) ions onto the chitosan derived Schiff bases obtained from the condensation of chitosan with salicyaldehyde (polymer I), 2,4-dihydroxybenzaldehyde (polymer II) and with 4-(diethylamino) salicyaldehyde (polymer III) in aqueous solutions was investigated. Batch adsorption experiments were carried out as a function of contact time, pH, and polymer mass. The amount of metal-ion uptake of the polymers was determined by using atomic absorption spectrometry (AAS) and the highest Cu(II) ions uptake was achieved at pH 7.0 and by using sodium perchlorate as an ionic strength adjuster for polymers I, II, and III. The isothermal behavior and the kinetics of adsorption of Cu(II) ions on these polymers with respect to the initial mass of the polymer and temperature were also investigated; adsorption isothermal equilibrium data could be clearly explained by the Langmuir equation. The experimental data of the adsorption equilibrium from Cu(II) solution correlates well with the Langmuir isotherm equation. 相似文献
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I. M. Ali A. A. El-Zahhar E. S. Zakaria 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(3):637-644
Summary Modification of the physico-chemical properties of hydrous titanium dioxide (TiO2) was conducted by using binding polyacrylonitrile (PAN) for the preparation of larger size particles having higher granular strength. The thermal behavior of the obtained composite has been studied by thermogravimetric and differential thermal analysis (TG/DTA). Sorption behavior of the TiO2-PAN composite for removal of some hazardous radionuclides has been studied at different conditions such as, pH, contact time, ion concentrations and reaction temperature as well as the drying temperature. The effects of interfering ions as well as some complexing agents on the distribution ratio of the sorption process have been determined. As a result of the obtained data the optimum conditions for the removal of the studied radionuclides were recommended. 相似文献
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Erwan Prignot Chanjuan Zhang Dr. Olivier Jeannin Dr. Zakaria Halime Dr. Rafael Gramage-Doria Dr. Franck Camerel 《欧洲无机化学杂志》2023,26(6):e202200591
Metal-bis(dithiolene) complexes derived from Ni(II), Co(II), Pd(II), Pt(II) and Au(III), bearing butyl aliphatic chains have been synthesized, and fully characterized by a variety of spectroscopic techniques including NMR, UV-vis, IR, HRMS, CV, and X-ray diffraction studies. This comparative study made possible to establish that the Co(II) species appear to be dimeric in the solid state as well as in solution. On the other hand, the coordination complexes based on Ni(II), Pd(II), Pt(II) and Au(III), feature a monomeric structure in both solution and solid state. These metal-bis(dithiolene) complexes are remarkably stable in solution and, in stark contrast to precedents in the literature, they retain their square planar geometry even in presence of pyridine derivatives reported for their apical binding on metal-bis(dithiolene) complexes. 相似文献
87.
The sorption of Fe(2+) onto unbleached kraft fibre was investigated at different conditions such as pH, temperature, and concentrations. The sorption, which increased with concentration and temperature, followed the Langmuir isotherm. Thermodynamically, the process was spontaneous and endothermic. It was found that the precipitation of Fe(2+) was highly dependent on pH and reached 100% when pH exceeded approximately 8. 相似文献
88.
Khalid Saifuddin Zakaria Irnie Azmi W. H. Mohamed W. A. N. W. 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1555-1567
Journal of Thermal Analysis and Calorimetry - Hybrid nanofluid is a new revolutionized cooling liquid with improved thermo-physical properties as compared to conventional coolant. This paper... 相似文献
89.
Ahmed Gaber Moamen S. Refat Arafa A.M. Belal Ibrahim M. El-Deen Nader Hassan Rozan Zakaria Majid Alhomrani Abdulhakeem S. Alamri Walaa F. Alsanie Essa M. Saied 《Molecules (Basel, Switzerland)》2021,26(8)
Herein, we report the synthesis of eight new mononuclear and binuclear Co2+, Ni2+, Cu2+, and Zn2+ methoxy thiosemicarbazone (MTSC) complexes aiming at obtaining thiosemicarbazone complex with potent biological activity. The structure of the MTSC ligand and its metal complexes was fully characterized by elemental analysis, spectroscopic techniques (NMR, FTIR, UV-Vis), molar conductivity, thermogravimetric analysis (TG), and thermal differential analysis (DrTGA). The spectral and analytical data revealed that the obtained thiosemicarbazone-metal complexes have octahedral geometry around the metal center, except for the Zn2+-thiosemicarbazone complexes, which showed a tetrahedral geometry. The antibacterial and antifungal activities of the MTSC ligand and its (Co2+, Ni2+, Cu2+, and Zn2+) metal complexes were also investigated. Interestingly, the antibacterial activity of MTSC- metal complexes against examined bacteria was higher than that of the MTSC alone, which indicates that metal complexation improved the antibacterial activity of the parent ligand. Among different metal complexes, the MTSC- mono- and binuclear Cu2+ complexes showed significant antibacterial activity against Bacillus subtilis and Proteus vulgaris, better than that of the standard gentamycin drug. The in silico molecular docking study has revealed that the MTSC ligand could be a potential inhibitor for the oxidoreductase protein. 相似文献
90.
Controlled Synthesis of Nanoporous Nickel Oxide with Two‐Dimensional Shapes through Thermal Decomposition of Metal–Cyanide Hybrid Coordination Polymers 下载免费PDF全文
Mohamed B. Zakaria Dr. Ming Hu Dr. Rahul R. Salunkhe Dr. Malay Pramanik Kimiko Takai Dr. Victor Malgras Prof. Seyong Choi Prof. Shi Xue Dou Prof. Jung Ho Kim Dr. Masataka Imura Dr. Shinsuke Ishihara Prof. Yusuke Yamauchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3605-3612
The urgent need for nanoporous metal oxides with highly crystallized frameworks is motivating scientists to try to discover new preparation methods, because of their wide use in practical applications. Recent work has demonstrated that two‐dimensional (2D) cyanide‐bridged coordination polymers (CPs) are promising materials and appropriate for this purpose (Angew. Chem. Int. Ed. 2013 , 52, 1235). After calcination, 2D CPs can be transformed into nanoporous metal oxides with a highly accessible surface area. Here, this strategy is adopted in order to form 2D nanoporous nickel oxide (NiO) with tunable porosity and crystallinity, using trisodium citrate dihydrate as a controlling agent. The presence of trisodium citrate dihydrate plays a key role in the formation of 2D nanoflakes by controlling the nucleation rate and the crystal growth. The size of the nanoflakes gradually increases by augmenting the amount of trisodium citrate dihydrate in the reaction. After heating the as‐prepared CPs in air at different temperatures, nanoporous NiO can be obtained. During this thermal treatment, organic units (carbon and nitrogen) are completely removed and only the metal content remains to take part in the formation of nanoporous NiO. In the case of large‐sized 2D CP nanoflakes, the original 2D flake‐shapes are almost retained, even after thermal treatment at low temperature, but they are completely destroyed at high temperature because of further crystallization in the framework. Nanoporous NiO with high surface area shows significant efficiency and interesting results for supercapacitor application. 相似文献