The utilization of carbon dioxide (CO₂) to enhance wellbore injectivity presents a cost-effective and sustainable strategy for mitigating greenhouse gas emissions while improving reservoir performance. This study introduces an environmentally friendly method employing a water-soluble chitosan salt (CS) that generates a carbonated-rich acid solution upon contact with dry CO₂ at 25 °C and 508 psi. CS solutions (100–2000 ppm) were prepared and evaluated for CO₂ uptake, acid generation, and rheological behavior. Results show that 1000 ppm achieves an optimal CO2 uptake (2612 mg/l), with moderate viscosity increase (from 1.52 to 3.37 cp), while higher concentrations exhibit a sharp rise due to polymer-like network formation. Core flooding tests revealed that 1000 ppm CS maximized pore-volume-to-breakthrough time (PVBT) and produced uniform, less branched wormholes as observed via CT imaging, indicating efficient acid penetration with minimal interface reaction resistance. These findings suggest that chitosan-based formulations offer a promising and sustainable pathway for CO₂ utilization and improved reservoir stimulation.
Background and Aim: due to the rapid growth of data communication and multimedia system applications, security becomes a critical issue in the communication and storage of images. This study aims to improve encryption and decryption for various types of images by decreasing time consumption and strengthening security. Methodology: An algorithm is proposed for encrypting images based on the Carlisle Adams and Stafford Tavares CAST block cipher algorithm with 3D and 2D logistic maps. A chaotic function that increases the randomness in the encrypted data and images, thereby breaking the relation sequence through the encryption procedure, is introduced. The time is decreased by using three secure and private S-Boxes rather than using si
... Show MoreMetasurface polarizers are essential optical components in modern integrated optics and play a vital role in many optical applications including Quantum Key Distribution systems in quantum cryptography. However, inverse design of metasurface polarizers with high efficiency depends on the proper prediction of structural dimensions based on required optical response. Deep learning neural networks can efficiently help in the inverse design process, minimizing both time and simulation resources requirements, while better results can be achieved compared to traditional optimization methods. Hereby, utilizing the COMSOL Multiphysics Surrogate model and deep neural networks to design a metasurface grating structure with high extinction rat
... Show MoreThis study presents a novel, custom‑built fluorescence detector for the precise determination of chloride and iodide ions based on their quenching effect on fluorescein. The detection system incorporates eight blue LEDs irradiation sources arranged at 0–90° angles relative to twin solar cell detectors connected. Two fluorescence quenching strategies were developed. The injected‑mixture mode (IMFQ) exhibited linear ranges of 0.00–1.00 mM for Cl⁻ and 0.00–1.25 mM for I⁻, with detection limits of 20 µM and 10 µmol L⁻¹, respectively. The continuous‑flow mode (CFFQ) demonstrated superior sensitivity with a dispersion factor of 1.33, wider linear ranges (0.1–6.0 m
In this paper it is required to enhance the performance of a mechanical system (here: a Hoisting System) where it is preferred to lift a different payloads with approximately the same speed of lifting and keeping at the same time the good performance, and this of course needs some intelligence of the system which will be responsible on measuring the present load and taking into account the speed and performance desired in order to achieve the requirements or the criteria. The process therefore is a Mechatronics System design which includes a measuring system, a control or automation technique, and an actuating system. The criteria built here in this research using a given Hoist system's characteristics and parameters and changing one of
... Show MoreBackground. In cases of spontaneous subarachnoid haemorrhage (SAH) with multiple intracranial aneurysms (MIAs) detected on angiography, some radiological clues assist in determining the site of a ruptured aneurysm which is bleeding is quite beneficial for the selection of the best treatment strategy. Case description. We report a case of a 60 years old patient who presented with spontaneous SAH, sellar hematoma, and three different aneurysms detected in angiography. Although the right Posterior communicating artery (PcomA) aneurysms showed Murphy’s teat on angiography intraoperatively, we discovered that the right superior hypophyseal aneurysm (SHA) was the source of the index bleeding. Both aneurysms were clipped successfully. Co
... Show MoreA simple and accurate method to determinate furosemide (FUR) based on converting the secondary amine to primary amine with acidic hydrolysis then azotization by nitrous acid and coupled with resorcinol as a coupling agent in aqueous medium at pH 13. The optical characteristic like beers law limit found to be (0.25-2.5) μg.ml−1, detection and quantification limits (0.0196) (0.0654) μg.ml−1respectivly and Sandel sensitivity was 0.006738 μg.cm−2. The least-square method was used to evaluate the regression equation and the correlation coefficient. The resulted azo dye has a maximum absorbance at 430 nm with light oran