The main objective of this study was to evaluate the adsorption efficiency of two adsorbent materials, Iraqi chicken eggshells (ESh) and activated carbon (AC) derived from ESh powder for the removal of a cationic dye (Janus green B; JGD) from aqueous solution. Activated carbon was synthesised from ESh using a simple chemical activation method using phosphoric acid as the activating agent. The physicochemical properties of the adsorbents were characterised by the Brunauer–Emmett–Teller (BET) method, FT-IR spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma optical emission spectroscopy (ICP-OES), and point of zero charge (pHpzc). The results of BET analysis confirmed that AC has a higher specific surface area (4.146 m2/g) compared to ESh (1.561 m2/g). The effects of operational parameters including contact time (5–60 min for ESh and 5–30 min for AC), adsorbent dose (0.05–1 g/10 mL), temperature (298–318 K), and pH (3.72–11.36) were systematically investigated. Optimal adsorption occurred at pH 11.36, where JGD removal efficiencies reached 90.13% with 0.2 g/10 mL of ESh after 60 min and 92.89% with 0.1 g/10 mL of AC after 30 min at 298 K. Equilibrium data were best fitted by the Freundlich isotherm model, yielding adsorption capacities of 0.09 mg/g for ESh and 1.85 mg/g for AC at 318 K and pH 5.5. The high correlation coefficient (R2 = 0.99) confirmed favourable heterogeneous adsorption. Kinetic data followed the pseudo-second-order model (R2 = 0.99). Thermodynamic parameters (ΔG°, ΔH°, ΔS°) indicated that JGD adsorption onto ESh was spontaneous (ΔG°<0), exothermic (ΔH°<0), and associated with decreased randomness (ΔS°<0), while adsorption onto AC was spontaneous (ΔG°<0), endothermic (ΔH°>0), and accompanied by increased randomness (ΔS°>0). The adsorption mechanism was attributed to electrostatic interactions, hydrogen bonding, and π–π interactions. Desorption experiments demonstrated that 0.2 mol/L HNO₃ effectively regenerated both adsorbents. After seven adsorption–desorption cycles, AC exhibited superior stability and reusability compared to ESh.
The aim of the research is to use the data content analysis technique (DEA) in evaluating the efficiency of the performance of the eight branches of the General Tax Authority, located in Baghdad, represented by Karrada, Karkh parties, Karkh Center, Dora, Bayaa, Kadhimiya, New Baghdad, Rusafa according to the determination of the inputs represented by the number of non-accountable taxpayers and according to the categories professions and commercial business, deduction, transfer of property ownership, real estate and tenders, In addition to determining the outputs according to the checklist that contains nine dimensions to assess the efficiency of the performance of the investigated branches by investing their available resources T
... Show MoreThe aim of this study is to investigate the ability of malachite green (MG) combined with 650nm diode laser to kill Candida albicans and to spectrally study the MG photodegradation after photodynamic therapy (PDT) spectrally. Cultures of Candida albicans were exposed to 40mW, 650 nm diode laser in the absence of MG. In PDT group, the MG was added to the Candida suspension for 5 min then exposed to diode laser for (5, 10, 15, 20) min at power density of 0.59W/cm2. The absorption spectrum of the photosensitized fungal suspension was obtained. The data were submitted to T-test (p<0.05). A 650nm diode laser in the presence of MG reduced the number of CFU/ml in 98.4%. Laser with 650nm alone and MG alone did not reduce significantly the num
... Show MoreGreen buildings are considered more efficient than traditional buildings due to the incorporated techniques and the multidisciplinary specializations required to comply with their specifications, in addition to the advanced commissioning, which undergoes before handing over the buildings to the owners to ensure requirements conformance. As a result, the appropriate selection of a project delivery system acts as the essential factor that affects the performance of the project. This research aims at building a system that helps to select the best method to implement green buildings. Through studying the recent research approaches in project delivery systems, the factors that affect the selection of the optimal implementation method fo
... Show MorePraise be to God, Lord of the Worlds, and prayers and peace be upon the Master of Messengers, and upon his family and companions
And whoever follows his guidance until the Day of Judgment. As for what follows: Islamic law commands Muslims to unite, reject disagreement, and not dispute, and to spread the spirit of tolerance and love among them. God Almighty said: “And hold fast to the rope of God all of you and do not become divided, and remember the favor of God upon you when you are enemies and He has joined your hearts.” So, by His grace, you became brothers (1), and He said: (And You will be like those who became divided and disagreed after the clear proofs had come to them. It is they - for them is a great punishment.) (2
... Show MoreThe current research aims to analyze the extent of the adoption of the standards of ISO 45001: 2018 for occupational safety and health management by the General Establishment of Civil Aviation. The research problem was the extent to which the General Establishment of Civil Aviation approved ISO 45001: 2018 for occupational safety and health management. The questionnaire was used as a primary data collection tool, the sample was distributed (50) form, they were selected from the category of employees of the establishment at different levels to represent the research community. Data were analyzed using the statistical package (SPSS), a number of vector statistical methods were used as well as arithmetic mean, standard deviation, an
... Show MoreNovel azo ligand based on tryptamine, and its metal complexes with antioxidant properties were synthesized through chemical methods and characterized through various techniques, including IR, Mass, UV-Vis spectroscopy, elemental analysis, conductivity, magnetic sensitivity, and thermogravimetric analysis. According to the IR spectra of the complexes, the azo-ligand, [5-(2-(3H- 1-indol-3-yl) ethyl) diazenyl) quinolin-8-ol] coordinates with metal ions through the nitrogen atom in the quinoline ring and the oxygen atom of the hydroxyl group. Thermal analysis techniques were employed to investigate the thermal behavior of the compounds. The results revealed that the metal complexes possess higher thermal stability compared to the free ligand. T
... Show MoreIn this work, two different laser dye solutions were used to host highly-pure silicon nitride nanoparticles as scattering centers to fabricate random gain media. The laser dye was dissolved in three different solvents (ethanol, methanol and acetone) and the final results were obtained for methanol only. The silicon nitride nanoparticles were synthesized by dc reactive magnetron sputtering technique with average particle size of 35 nm. The random gain medium was made as a solid rod with high spectral efficiency and low production cost. Optical emission with narrow linewidth was detected at 532-534 nm as 9 mg of silicon nitride nanoparticles were added to the 10 -5 M dye solution. The FWHM of 0.3 and 3.52 nm was determined for Rhodamine B and
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