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We propose and discuss two models that take into account the decreasing of the bulk density of dyes molecules in contact with a porous electrode. We show that the models based on the standard adsorption phenomenon have to be considered just as fitting models, of limited physical significance. A more physical model has to take into account the diffusion of dye molecules into the channels present in the porous electrode and also the adsorption of dye molecules on the lateral surfaces of these channels. The agreement between the theoretical prediction of such a model and the experimental data is reasonably good. 相似文献
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Fazaeli Yousef Hosseini Mohammad Amin Shahabinia Fatemeh Feizi Shahzad 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(1):201-207
Journal of Radioanalytical and Nuclear Chemistry - Porphyrins and 68Ga have emerged as novel synergic options for PET applications so the idea of preparation of a novel porphyrin complex using this... 相似文献
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Nafisa Gull Shahzad Maqsood Khan Muhammad Taqi Zahid Butt Saba Zia Syed Khalid Atif Islam Imran Sajid Rafi Ullah Khan Martin William King 《先进技术聚合物》2019,30(9):2414-2424
Hydrogel‐based drug delivery systems can leverage therapeutically favorable upshots of drug release and found clinical uses. Hydrogels offer temporal and spatial control over the release of different therapeutic agents. Because of their tailor made controllable degradability, physical properties, and ability to prevent the labile drugs from degradation, hydrogels provide platform on which diverse physicochemical interactions with entrapped drugs cause to control drug release. Herein, we report the fabrication of novel vinyltrimethoxy silane (VTMS) cross‐linked chitosan/polyvinyl pyrrolidone hydrogels. Swelling in distilled water in conjunction with different buffer and electrolyte solutions was performed to assess the swellability of hydrogels. Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X‐ray diffraction (XRD) analysis were further conducted to investigate the possible interactions between components, thermal stability, and crystallinity of as‐prepared hybrid hydrogels, respectively. In vitro time‐dependent biodegradability, antimicrobial study, and cytotoxicity were also carried out to evaluate their extensive biocompatibility and cytotoxic behavior. More interestingly, in vitro drug release study allowed for the controlled release of cephradine. Therefore, this facile strategy developed the novel biocompatible and biodegradable hybrid hydrogels, which could significantly expand the scope of these hydrogels in other biomedical applications like scaffolds, skin regeneration, tissue engineering, etc. 相似文献
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Hamid Latif M. Shahid Rafique R.S. Rawat Shahzad Naseem 《Applied Surface Science》2008,254(22):7505-7511
In the paper an attempt has been made to use the laser-induced plasma as an X-ray source for the growth of nanostructures on the surface of gold. For this purpose, an Nd:YAG laser operated at second harmonics (λ = 532 nm, E = 400 mJ) is used to produce plasma from analytical grade 5N pure Al, Cu and W targets. An analytical grade (5N pure) gold substrate was irradiated by X-rays generated from Al, Cu and W plasma under the vacuum ∼10−4 Torr. The surface was analyzed by two techniques, XRD and AFM. The aberrations in the XRD peaks show that there are significant structural changes in the exposed gold, in terms of decreased reflection intensities, increased dislocation line density, changes in the d-spacing and disturbance in the periodicity of the planes. AFM used to explore the topography of the irradiated gold reveals that regardless of the source, nm sized hillocks have been produced on the gold surface. The roughness of the surface has increased due to the growth of these hillocks. 相似文献
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Faizan Ur Rahman Maryam Bibi Ezzat Khan Abdul Bari Shah Mian Muhammad Muhammad Nawaz Tahir Adnan Shahzad Farhat Ullah Muhammad Zahoor Salman Alamery Gaber El-Saber Batiha 《Molecules (Basel, Switzerland)》2021,26(15)
In this study six unsymmetrical thiourea derivatives, 1-isobutyl-3-cyclohexylthiourea (1), 1-tert-butyl-3-cyclohexylthiourea (2), 1-(3-chlorophenyl)-3-cyclohexylthiourea (3), 1-(1,1-dibutyl)-3-phenylthiourea (4), 1-(2-chlorophenyl)-3-phenylthiourea (5) and 1-(4-chlorophenyl)-3-phenylthiourea (6) were obtained in the laboratory under aerobic conditions. Compounds 3 and 4 are crystalline and their structure was determined for their single crystal. Compounds 3 is monoclinic system with space group P21/n while compound 4 is trigonal, space group R3:H. Compounds (1–6) were tested for their anti-cholinesterase activity against acetylcholinesterase and butyrylcholinesterase (hereafter abbreviated as, AChE and BChE, respectively). Potentials (all compounds) as sensing probes for determination of deadly toxic metal (mercury) using spectrofluorimetric technique were also investigated. Compound 3 exhibited better enzyme inhibition IC50 values of 50, and 60 µg/mL against AChE and BChE with docking score of −10.01, and −8.04 kJ/mol, respectively. The compound also showed moderate sensitivity during fluorescence studies. 相似文献
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Nazir Muhammad Shahzad Ghasemi Ali Dezfulizadeh Amin Abdalla Ahmad N. 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2653-2664
Journal of Thermal Analysis and Calorimetry - The aim of this work is the energy analysis of a novel semicircle-shaped parabolic trough solar collector filled with the water–boehmite alumina... 相似文献