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Simulation of Enzyme Catalysis in Calcium Alginate Beads
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A general mathematical model for a fixed bed immobilized enzyme reactor was developed to simulate the process of diffusion and reaction inside the biocatalyst particle. The modeling and simulation of starch hydrolysis using immobilized α-amylase were used as a model for this study. Corn starch hydrolysis was carried out at a constant pH of 5.5 and temperature of . The substrate flow rate was ranging from 0.2 to 5.0 mL/min, substrate initial concentrations 1 to 100 g/L. α-amylase was immobilized on to calcium alginate hydrogel beads of 2 mm average diameter. In this work Michaelis-Menten kinetics have been considered. The effect of substrate flow rate (i.e., residence time) and initial concentration on intraparticle diffusion have been taken into consideration. The performance of the system is found to be affected by the substrate flow rate and initial concentrations. The reaction is controlled by the reaction rate. The model equation was a nonlinear second order differential equation simulated based on the experimental data for steady state condition. The simulation was achieved numerically using FINITE ELEMENTS in MATLAB software package. The simulated results give satisfactory results for substrate and product concentration profiles within the biocatalyst bead.

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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
Laminar Free Convection In Horizontal Annulus Filled With Glass Beads And With Annular Fins On The Inner Cylinder
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An experimental and numerical study has been carried out to investigate the heat transfer by natural convection and radiation in a two dimensional annulus enclosure filled with porous media (glass beads) between two horizontal concentric cylinders. The outer cylinders are of (100, 82 and70mm) outside diameters and the inner cylinder of 27 mm outside diameter with (or without) annular fins attached to it. Under steady state condition; the inner cylinder surface is maintained at a high temperature by applying a uniform heat flux and the outer cylinder surface at a low temperature inside a freezer. The experiments were carried out for an annulus filled with
glass beads at a range of modified Rayleigh number (4.9 ≤ Ra≤ 69), radiation

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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Production of Protease Enzyme from Wheat Straw
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      Protease enzyme production was studied and optimized as  a first step to collect information about solid state fermenter) to produce protease enzyme. A local isolated Aspergillus niger was used for this study with constant spores feeding in every experiment at (105/g). Experiments carried out in conical flasks with (250 ml) containing (10 g) of wheat straw as a substrate with different conditions included temperature, pH, hydration ratio, and fermentation time, the results comprised by measuring protease activity (u). The results showed that the best activity can be obtained at (T = 32°C, t= 100 hrs, pH= 2.5 and hydration ratio is 1:3). On the other hand the results is courage to p

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Publication Date
Thu Dec 01 2011
Journal Name
Iraqi Journal Of Physics
Synthesis of calcium hydroxyapatite powder from hen’s eggshell
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The interest in calcium phosphates arises from the fact that bones contain a high percentage of mineralized calcium phosphate . In this study, pure and biocompatible hydroxyapatite (HAP) powder was successfully synthesized using hen’s egg shell as calcium source and phosphoric acid by precipitation method.The precipitate obtained was subjected to ripenning process for 24 hours, filtered, air dried, and calcined at temperatures of 400,800,900,and 1000 ºC.
X-Ray diffraction(XRD) technique was used to investigate the formation of HAP powder, XRD results revealed the HAP formation and also indicate no occurrence of secondary phases. Fourier Transform Infrared(FT-IR) spectrum shows the characterstic peaks for phosphate and hydroxyl grou

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Publication Date
Wed Mar 29 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Calcium, Magnesium and Phosphorous Levels in Serum of Iraqi Women with Fibromyalgia
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         Fibromyalgia (FM) is a common, debilitating, and chronic pain syndrome. The women are more likely to have more tender points on examination than are their male counterparts. Iraqi study showed that FM occur in 1.5% among adolescents of Iraqi population. In compare to normal healthy women, present study was revealed that Iraqi women with FM have significant elevation of calcium (p = 0.003) with significant reduction of magnesium (p = 0.001), whereas the inorganic phosphorous was not differs (p = 0.31). In conclusion, magnesium and calcium would play a crucial role in etiopathogenesis of fibromyalgia.

Key words: calcium, magnesium, phosphorous, Fibromyalgia.

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Enhancing Nitrate Ion Removal from Water using Fixed Bed Columns with Composite Chitosan-based Beads
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    Water contamination is a pressing global concern, especially regarding the presence of nitrate ions. This research focuses on addressing this issue by developing an effective adsorbent for removing nitrate ions from aqueous solutions. two adsorbents Chitosan-Zeolite-Zirconium (Cs-Ze-Zr composite beads and Chitosan-Bentonite-Zirconium Cs-Bn-Zr composite beads were prepared. The study involved continuous experimentation using a fixed bed column with varying bed heights (1.5 and 3 cm) and inlet flow rates (1 and 3 ml/min). The results showed that the breakthrough time increased with higher bed heights for both Cs-Ze-Zr and Cs-Bn-Zr composite beads. Conversely, an increase in flow rate led to a decrease in breakthrough time. Notab

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Publication Date
Sat Sep 06 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of sodium fluoride addition as a disinfectant on some properties of alginate impression material
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Background: Impression materials, impression trays, and poured stone cast have been said to be the main source of cross infection between patients and dentists. However, it was observed that disinfection of the impression is not performed systematically in routine dental practice. Disinfection of alginates either by immersion or spray technique was found to cause dimensional inaccuracies, although with proper disinfection of alginates there were small dimensional changes. A variety of fluoride releasing products designed for topical use is currently available. Following their use, varied amount of fluoride is systemically absorbed depending on the fluoride concentration and the manner of its use. The objective of this study was to evaluate

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Publication Date
Tue Nov 14 2023
Journal Name
International Journal Of Dentistry
Antimicrobial Efficiency of Hypochlorous Acid and Its Effect on Some Properties of Alginate Impression Material
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Dental clinicians and professionals need an affordable, nontoxic, and effective disinfectant against infectious microorganisms when dealing with the contaminated dental impressions. This study evaluated the efficiency of hypochlorous acid (HOCl) as an antimicrobial disinfectant by spraying technique for the alginate impression materials, compared with sodium hypochlorite, and its effect on dimensional stability and reproduction of details. HOCl with a concentration of 200 ppm for 5 and 10 min was compared with the control group (no treatment) as a negative control and with sodium hypochlorite (% 0.5) as a positive control. Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa were selected to assess the antimicrobi

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Publication Date
Fri Jan 19 2024
Journal Name
Baghdad Science Journal
GRHPR gene variations in Iraqi patients infected with calcium oxalate kidney stones
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      The alterations in glyoxylate reductase and hydroxy-pyruvate reductase concentrations in the sera and the genetic alterations associated with calcium oxalate kidney stones in Iraqi patients were not studied previously so this study aimed to focus on these points. This study included 80 subjects; they were 50 patients with calcium oxalate stones compared to 30 apparently healthy controls. Biochemical investigations for kidney functions (creatinine, urea, and uric acid), were performed on the sera of both groups. Also, complete blood count, random blood sugar, and blood group tests. Furthermore, urine had been collected for General Urine Examination to visualize oxalate crystals in the urine of the patient. Also, the GRHPR

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Publication Date
Tue Dec 27 2022
Journal Name
Chemical Papers
Synthesis, characterization, and application of external gelation of sodium alginate nanoparticles in molecular imprinting for separation and drug delivery of tenoxicam
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Publication Date
Wed Nov 01 2023
Journal Name
Journal Of Dentistry
The in-vitro development of novel enzyme-based chemo-mechanical caries removal agents
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Objectives Bromelain is a potent proteolytic enzyme that has a unique functionality makes it valuable for various therapeutic purposes. This study aimed to develop three novel formulations based on bromelain to be used as chemomechanical caries removal agents. Methods The novel agents were prepared using different concentrations of bromelain (10–40 wt. %), with and without 0.1–0.3 wt. % chloramine T or 0.5–1.5 wt. % chlorhexidine (CHX). Based on the enzymatic activity test, three formulations were selected; 30 % bromelain (F1), 30 % bromelain-0.1 % chloramine (F2) and 30 % bromelain-1.5 % CHX (F3). The assessments included molecular docking, Fourier-transform infrared spectroscopy (FTIR), viscosity and pH measurements. The efficiency

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