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Degradation of direct azo dye by Cucurbita pepo free and immobilized peroxidase

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Journal of Environmental Sciences 2013年第6期25卷 1235-1244页

作者： Nabila Boucherit mahmoud Abouseoud Lydia Adour Université mouloud mammeri Laboratoire de Biomatériaux et de Phénomènes deTransports Université Dr.Yahia Fares Laboratoire de Biomatériaux et de Phénomènes de Transports Université Dr.Yahia Fares Laboratoire de Génie de la Réaction Faculté de Génie Mécanique et Génie des ProcédésUniversité Houari Boumediene Laboratoire des Biotechnologies Environnementales et Génie des Procédés

Enzymatic decolourization of the azo dye, Direct Yellow （DY 106） by Cucurbita pepo （courgette） peroxidase （CP） is a complex process, which is greatly affected by ph, temperature, enzyme activity and the concentrations of h202 and dye. Courgette peroxidase was extracted and its performance was evaluated by using the free-CP （FCP） and immobilized-CP （ICP） forms in the decolourization of DY106. Immobilization of peroxidase in calcium alginate beads was performed according to a strategy aiming to minimize enzyme leakage and keep its activity at a maximum value by optimizing sodium alginate content, enzyme loading and calcium chloride concentration. The initial conditions ~it which the highest DY106 decolourization yield was obtained were found at ph 2, temperature 20~C, h202 dose 1 mmol/L （FCP） and 100 mmol/L （ICP）. The highest decolourization rates were obtained for dye concentrations 50 mg/L （FCP） and 80 mg/L （ICP）. Under optimal conditions, the FCP was able to decolorize more than 87% of the dye within 2 min. While with ICP, the decolourization yield was 75% within 15 rain. The decolourization and removal of DY106 was proved by UV-Vis analysis. Fourier transform infrared （FF-IR） spectroscopy analysis was also performed on DY106 and enzymatic treatment precipitated byproduct.

关键词： Cucurbita pepo peroxidase immobilization decolourization azo dye

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maximizing the Benefit of Rate Transient Analysis for Gas Condensate Reservoirs

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Energy Engineering 2021年第5期118卷 1411-1423页

作者： mahmoud Abdo Tantawy Ahmed A.m.Elgibaly Ahmed mohamed Farag Faculty of Petroleum and mining Engineering Suez UniversitySuezEgypt Abu Qir Petroleum Company AlexandriaEgypt

In recent years,many trials have been made to use the Rate Transient Analysis(RTA)techniques as a method to describe the gas condensate *** problem with using these techniques is the multi-phase behavior of the gas condensate ***,the Pressure Transient Analysis(PTA)is commonly used in this case to analyze the reservoir *** this paper,we are going to compare the results of both PTA and RTA of three wells in gas condensate *** comparison showed a great match between the results of the two mentioned techniques for the first time using a reference GOR of 75,000 SCF/***,we concluded that we could depend on RTA instead of PTA to spare the cost associated with the PTA in the gas condensate reservoirs.

关键词： Rate transient analysis production data analysis well testing permeability skin factor gas condensate

Effective damping of local low frequency oscillations in power systems integrated with bulk PV generation

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Protection and Control of modern Power Systems 2021年第1期6卷 512-524页

作者： Ahmed hesham Abd El-Kareem mohamed Abd Elhameed mahmoud m.Elkholy Operation Engineer at New Capital Power Plant New Capital CityEgypt Electrical Power and machines Department Faculty of EngineeringZagazig UniversityZagazigEgypt

high penetration of renewable sources into conventional power systems results in reduction of system inertia and noticeable low-frequency oscillations (LFOs) in the rotor speed of synchronous generators. In this paper, we propose effective damping of LFOs by incorporating a supplementary damping controller with a photovoltaic (PV) generating station, where the parameters of this controller are coordinated optimally with those of a power system stabilizer (PSS). The proposed method is applied to damp local electromechanical modes by studying a system comprising a synchronous generator and a PV station connected to an infinite bus. The PV station is modeled following the instructions of the Western Electricity Coordinating Council. The problem is modeled as an optimization problem, where the damping ratio of the electromechanical modes is designed as the objective function. Constraints including upper and lower limits of decision parameters and damping ratio of other modes are considered by imposing penalties on the objective function. Different optimization algorithms are used to pursue the optimal design, such as political, improved gray wolves and equilibrium optimizers. The results validate the effectiveness of the proposed controller with PSS in damping local modes of oscillations.

关键词： Low frequency oscillations Damping controller PV WECC

Profitability analysis of a femtosecond laser system for cataract surgery using a fuzzy logic approach

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International Journal of Ophthalmology(English edition) 2016年第7期9卷 1046-1050页

作者： Jose Antonio Trigueros David P Pinero mahmoud m Ismail Department of Financial Economic and Accounting Miguel Hernandez University Elche 03202 Alicante Spain Department of Optics Pharmacology and AnatomyUniversity of Alicante Crta San Vicente del RaspeigAlicante 03690 Spain Al-Azhar University Cairo 11651 Egypt

AIm：To define the financial and management conditions required to introduce a femtosecond laser system for cataract surgery in a clinic using a fuzzy logic ***：In the simulation performed in the current study,the costs associated to the acquisition and use of a commercially available femtosecond laser platform for cataract surgery（VICTUS,TEChNOLAS Perfect Vision Gmbh,Bausch ＆ Lomb,munich,Germany） during a period of 5y were considered.A sensitivity analysis was performed considering such costs and the countable amortization of the system during this 5y ***,a fuzzy logic analysis was used to obtain an estimation of the money income associated to each femtosecond laser-assisted cataract surgery（G）. RESULTS：According to the sensitivity analysis,the femtosecond laser system under evaluation can be profitable if 1400 cataract surgeries are performed per year and if each surgery can be invoiced more than $*** contrast,the fuzzy logic analysis confirmed that the patient had to pay more per surgery,between $661.8 and $667.4 per surgery,without considering the cost of the intraocular lens（IOL）.CONCLUSION：A profitability of femtosecond laser systems for cataract surgery can be obtained after a detailed financial analysis,especially in those centers with large volumes of *** cost of the surgery for patients should be adapted to the real flow of patients with the ability of paying a reasonable range of cost.

关键词： cataract surgery femtosecond laser fuzzy logic femto-cataract victus profitability analysis

Amino Acid Encryption method Using Genetic Algorithm for Key Generation

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Computers, materials & Continua 2022年第1期70卷 123-134页

作者： Ahmed S.Sakr m.Y.Shams Amena mahmoud mohammed Zidan Department of Information System Faculty of Computers and InformationMenofia UniversityEgypt Department of machine learning and Information Retrieval Faculty of Artificial IntelligenceKafrelsheikh UniversityEgypt Department of Computer Science Faculty of Computers and InformationKafrelshiekh UniversityEgypt hurghada Faculty of Computers and Artificial Intelligence South Valley UniversityEgypt

In this new information era,the transfer of data and information has become a very important *** data must be kept secured from unauthorized persons using *** science of cryptography depends not only on complex mathematical models but also on encryption *** acid encryption is a promising model for data *** this paper,we propose an amino acid encryption model with two encryption *** first key is generated randomly using the genetic *** second key is called the protein key which is generated from converting DNA to a protein ***,the protein message and the first key are used in the modified Playfair matrix to generate the cypher *** experimental results show that the proposed model survives against known attacks such as the Brute-force attack and the Ciphertext-only *** addition,the proposed model has been tested over different types of characters including white spaces and special characters,as all the data is encoded to 8-bit *** performance of the proposed model is compared with other models using encryption time and decryption *** model also balances all three principles in the CIA triad.

关键词： Cryptography amino acid genetic algorithm playfair deep learning DNA computing

Data mining Approach Based on hierarchical Gaussian mixture Representation model

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Intelligent Automation & Soft Computing 2023年第3期35卷 3727-3741页

作者： hanan A.hosni mahmoud Alaaeldin m.hafez Fahd Althukair Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Information Systems College of Computer and Information SciencesKing Saud UniversityRiyadhSaudi Arabia Department of Electrical Engineering and Computer Sciences College of EngineeringUniversity of CaliforniaBerkeleyUSA

Inﬁnite Gaussian mixture process is a model that computes the Gaus-sian mixture parameters with *** process is a probability density distribu-tion with adequate training data that can converge to the input density *** this paper,we propose a data mining model namely Beta hierarchical distribution that can solve axial data modeling.A novel hierarchical Two-hyper-Parameter Poisson stochastic process is developed to solve grouped data *** solution uses data mining techniques to link datum in groups by linking their *** learning techniques are novel presentations of Gaussian model-ling that use prior knowledge of the representation hyper-parameters and approx-imate them in a closed *** are performed on axial data modeling of Arabic Script classiﬁcation and depict the effectiveness of the proposed method using a hand written benchmark dataset which contains complex handwritten Ara-bic *** are also performed on the application of facial expres-sion recognition and prove the accuracy of the proposed method using a benchmark dataset which contains eight different facial expressions.

关键词： Data classiﬁcation handwritten Arabic classiﬁcation facial expressions

Comparisons between unsteady sediment-transport modeling

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Journal of Central South University 2013年第2期20卷 536-540页

作者： Lahouari Benayada mahmoud hasbaia Department of Architecture University of Sciences and Technology Department of hydraulics University of M’Sila

The comparative study between unsteady flow models in alluvial streams shows a chaotic residue as for the choices of a forecasting model. The difficulty resides in the choice of the expressions of friction resistance and sediment transport. Three types of mathematical models were selected. models of type one and two are fairly general, but require a considerable number of boundary conditions, which related to each size range of sediments. It can be a handicap during rivers studies which are not very well followed in terms of experimental measurements. Also, the use of complex models is not always founded. But then, the model of type three requires a limited number of boundary conditions and solves only a system of three equations at each time step. It allows a considerable saving in calculating times.

关键词： friction resistance bed load suspended load mobile-bed modeling

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Thermal radiation effect on flow and heat transfer of unsteady mhD micropolar fluid over vertical heated nonisothermal stretching surface using group analysis

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Applied mathematics and mechanics(English Edition) 2013年第6期34卷 703-720页

作者： I. A. hASSANIEN h. m. EL-hAWARY m. A. A. mahmoud R. G. ABDEL-RAhmAN A. S. ELFEShAWEY Department of mathematics Faculty of Science Assuit University Department of mathematics Faculty of Science Benha University

The aim of this paper is to study the thermal radiation effects on the flow and heat transfer of an unsteady magnetohydrodynamic （mhD） micropolar fluid over a vertical heated nonisothermal stretching surface in the presence of a strong nonuniform magnetic field. The symmetries of the governing partial differential equations are de- termined by the two-parameter group method. One of the resulting systems of reduced nonlinear ordinary differential equations are solved numerically by the Chebyshev spec- tral method. The effects of various parameters on the velocity, the angular velocity, and the temperature profiles as well as the skin-friction coefficient, the wall couple stress co- efficient, and the Nusselt number are studied.

关键词： thermal radiation micropolar fluid unsteady flow group theoretic method,Chebyshev spectral method

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Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.ImRAN T.ASGhAR Z.ABBAS Department of mathematics Division of Science and TechnologyUniversity of Education Department of mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(hAm).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： hybrid nanofluid oscillating curved stretchable sheet gyrotactic microorganism Cattaneo-Christov heat and mass flux chemical reaction analytical solution O368