تم في هذه الدراسة ، تزيين رقائق أكسيد الجرافين (GO) بجسيمات كوبلتيت النيكل النانوية NiCo2O4(NC) عن طريق الترسيب في الموقع ، وتم استخدام المتراكب المحضر (NC: GO) كسطح ماز لإزالة صبغة الميثيل الخضراء ( MG) من المحاليل المائية. تم التحقق من التغطية الناجحة لأوكسيد الجرافين بجزيئات كوبلتيت النيكل النانوية (NC) باستخدام دراسات FT-IR وحيود الأشعة السينية (XRD). كانت أحجام الجسيمات البلورية لل NC و لل GO المزين ب NCهي 10.53 نانوميتر 9.30 نانومتر على التوالي. تم دراسة تأثير العديد من العوامل التجريبية ، بما في ذلك زمن التلامس ، وكمية السطح الماز ، ودرجة الحرارة. كان وقت التلامس الأمثل وكمية السطح 120 دقيقة و 3 مجم / لتر على التوالي. تتلائم بيانات الامتزاز بشكل أفضل مع ايزوثيرم Freundlich. تم استخدام أربعة نماذج حركية لتتبع عملية الامتزاز: معادلة زائفة من الدرجة الأولى ، ومعادلة زائفة من الدرجة الثانية ، ومعادلة الانتشار داخل الجسيمات ، ومعادلة بويد. أظهرت نمذجة البيانات التجريبية أن حركية الامتزاز كانت ممثلة بشكل جيد بنموذج الرتبة الثانية الزائفة (R2 = 0.9945) مع معدل ثابت سرعة يبلغ 3.2 × 10 - 3 (جم / مجم. دقيقة). يتم امتصاص صبغة MG تدريجيًا بواسطة الجسيمات النانوية NC من خلال الانتشار داخل الجسيمات ويتم الاحتفاظ بها بعد ذلك في مسام أصغر. أظهرت قيم التحليل الديناميكي الحراري أن عملية امتزاز صبغة MG كانت ماصة للحرارة بطبيعتها ، و تلقائية وعملية الامتزاز فيزيائية. الكلمات المفتاحية: الانتشار داخل الجسيمات ، المسافات البينية، النموذج الزائف من الدرجة الأولى ، معادلة بويد
Integration of laminar bubbling flow with heat transfer equations in a novel internal jacket airlift bioreactor using microbubbles technology was examined in the present study. The investigation was accomplished via Multiphysics modelling to calculate the gas holdup, velocity of liquid recirculation, mixing time and volume dead zone for hydrodynamic aspect. The temperature and internal energy were determined for heat transfer aspect.
The results showed that the concentration of microbubbles in the unsparged area is greater than the chance of large bubbles with no dead zones being observed in the proposed design. In addition the pressure, due to the recirculation velocity of liquid around the draft
... Show MoreKE Sharquie, AA Noaimi, ZT Burhan, Journal of Cosmetics, Dermatological Sciences and Applications, 2016 - Cited by 9
This study has contributed to understanding a delayed prey-predator system involving cannibalism. The system is assumed to use the Holling type II functional response to describe the consuming process and incorporates the predator’s refuge against the cannibalism process. The characteristics of the solution are discussed. All potential equilibrium points have been identified. All equilibrium points’ local stability analyses for all time delay values are investigated. The system exhibits a Hopf bifurcation at the coexistence equilibrium, which is further demonstrated. The center manifold and normal form theorems for functional differential equations are then used to establish the direction of Hopf bifurcation and the stability of the per
... Show MoreIn the present research synthesis and study of biological activity a series of new polymers modified of chitosan with compounds containing azo group. Beginning diazonium salt produced from 3,3'-dimethyl-[1,1'-biphenyl]-4,4'-diamine reacted with concentrated HCl acid and sodium nitrite. The coupling reaction between diazonium salt with substituted aromatic aldehyde to produce Azo derivatives )1-6(. Azo Schiff bases Chitosan )7-12( were synthesized by condensation of Chitosan with Azo derivatives )1-6( in ethanol with some drops of glacial acetic acid. The structural modifications of Chitosan ring (linked to a bioactive azo moiety) were expected to give new derivatives )7-12( with a diverse range of biological functions. These compounds' st
... Show MoreSteady natural and mixed convection flow in a square vented enclosure filled with water-saturated aluminum metal foam is numerically investigated. The left vertical wall is kept at constant temperature and the remaining walls are thermally insulated. Forced convection is imposed by providing an inlet at cavity bottom surface, and a vent at the top surface. Natural convection takes place due to the temperature difference inside the enclosure. Darcy-Brinkman-Forchheimer model for fluid flow and the two-equation of the local thermal non-equilibrium model for heat flow was adopted to describe the flow characteristics within the porous cavity. Numerical results are obtained for a wide range of width of the inlet as a fraction
... Show MoreThe fingerprints are the more utilized biometric feature for person identification and verification. The fingerprint is easy to understand compare to another existing biometric type such as voice, face. It is capable to create a very high recognition rate for human recognition. In this paper the geometric rotation transform is applied on fingerprint image to obtain a new level of features to represent the finger characteristics and to use for personal identification; the local features are used for their ability to reflect the statistical behavior of fingerprint variation at fingerprint image. The proposed fingerprint system contains three main stages, they are: (i) preprocessing, (ii) feature extraction, and (iii) matching. The preprocessi
... Show MoreObjectives: Two derivatives of cephalexin were synthesized by reaction with isatin-glycine Schiff base and bromoisatin-glycine Schiff base separately. Methods: Cephalexin was linked through the amine group to isatin glycine and bromoisatin glycine Schiff bases by amide bond formation. Results: These derivatives were characterized by FT-IR, H-NMR, elemental CHN analysis and then tested for their antimicrobial activity compared to cephalexin against gram-positive, gram-negative bacteria and Candida albicans fungi. Conclusion: The two compounds showed better activity against Staphylococcus aureus, compound 3b is more active against Escherichia coli, and compound 3a is more active against Klebsiella pneumonia.