The current study was to examine the reliability and effectiveness of using most abundant, inexpensive waste in the form of scrap raw zero valent aluminum ZVAI and zero valent iron ZVI for the capture, retard, and removal of one of the most serious and hazardous heavy metals cadmium dissolved in water. Batch tests were conducted to examine contact time (0-250) min, sorbent dose (0.25-1 g ZVAI/100 mL and 2-8 g ZVI/100 mL), initial pH (3-6), pollutant concentration of 50mg/L initially, and speed of agitation (0-250) rpm . Maximum contaminant removal efficiency corresponding to (90 %) for cadmium at 250 min contact time, 1g ZVAI/ 6g ZVI sorbent mass ratio, pH 5.5, pollutant concentration of 50 mg/L initially, and 250 rpm agitation speed were obtained. Langmuir and Freundlich isotherms were presumed to fit the batch kinetics data for the sorption of Cd(II) onto ZVAI and/or ZVI and found that Langmuir (I) was the most representative model type with coefficient of determination R2 greater than 0.9115. Kinetics data for the sorption of Cd(II) onto ZVAI/ZVI mixture and due to the good agreement between the fitted and the experimental results; the data was found to obey the pseudo second order model. The scanning electron microscopy (SEM) for the ZVI and ZVAI was conducted before and after the sorbent-liquid reaction and revealed distinct morphological changes in the sorbent surface due to the contaminant saturation and pore channel blockages that ceased the sorption process.
Markov chains are an application of stochastic models in operation research, helping the analysis and optimization of processes with random events and transitions. The method that will be deployed to obtain the transient solution to a Markov chain problem is an important part of this process. The present paper introduces a novel Ordinary Differential Equation (ODE) approach to solve the Markov chain problem. The probability distribution of a continuous-time Markov chain with an infinitesimal generator at a given time is considered, which is a resulting solution of the Chapman-Kolmogorov differential equation. This study presents a one-step second-derivative method with better accuracy in solving the first-order Initial Value Problem
... Show MoreOptical fiber technology is without a doubt one of the most significant phases of the communications revolution and is crucial to our daily lives. Using the free version (2022) of RP Fiber Calculator, the modal properties for optical fibers with core radii (1.5−7.5) μm, core index (1.44−1.48) and cladding index (1.43−1.47) have been determined at a wavelength of 1000 nm. When the fiber core’s radius is larger than its operating wavelength, multimode fibers can be created. The result is a single-mode fiber in all other cases. All of the calculated properties, it has been shown, increase with increasing core radius. The modes’ intensity profiles were displayed.
This study investigated the shear performance of concrete beams with GFRP stirrups vs. traditional steel stirrups. Longitudinal glass fiber‐reinforced polymer (GFRP) bars were used to doubly reinforce the tested beams at both the top and bottom of their cross sections. To accomplish this, several stirrup spacings were provided. Eight beam specimens, measuring 300 × 250 × 2400 mm, were used in an experimental program to test under a two‐point concentrated load with an equal span‐to‐depth ratio until failure. Four beams in Group I have standard mild steel stirrups of 8 mm diameter, while four beams in Group II have GFRP stirrups with the same adopted diameter. The difference betwe
The growing demand for optical fibers is due to their superior the ability to transmit information with high efficiency and minimal loss across extensive distances. In this study, four optical fibers with core radii ranging from (2.05-5.05) μm, and with a numerical aperture of 0.1624 were analyzed. The modal properties of these fibers were calculated at a wavelength of 1030 nm using the RP Fiber Calculator software (free version 2025). Furthermore, the impact of increasing the core radius on these properties was examined. The results showed that multimode fibers are formed when the core radius is much larger than the wavelength used. In contrast, single-mode fiber is obtained when th
سرطان البنكرياس هو مرض ذو معدل وفيات مرتفع، ولا يزال التشخيص المبكر لسرطان البنكرياس يمثل تحديًا. يظل معدل البقاء النسبي لمدة 5 سنوات أقل من 8%، والاستراتيجيات العلاجية غير فعالة في زيادة معدلات بقاء المريض على قيد الحياة. في خلايا سرطان البنكرياس، ارتبطت مقاومة العلاج بالتغيرات الجينية التي تؤدي إلى ظهور مسارات خلوية شاذة؛ ولذلك، هناك ما يبرر ايجاد استراتيجيات جديدة لعلاج هذا المرض. هنا، سعينا لاستكشاف
... Show MoreThis study investigated the shear performance of concrete beams with GFRP stirrups vs. traditional steel stirrups. Longitudinal glass fiber‐reinforced polymer (GFRP) bars were used to doubly reinforce the tested beams at both the top and bottom of their cross sections. To accomplish this, several stirrup spacings were provided. Eight beam specimens, measuring 300 × 250 × 2400 mm, were used in an experimental program to test under a two‐point concentrated load with an equal span‐to‐depth ratio until failure. Four beams in Group I have standard mild steel stirrups of 8 mm diameter, while four beams in Group II have GFRP stirrups with the same adopted diameter. The difference betwe