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New simple spectrophotometric method for determination of the binary mixtures(atorvastatin calcium and ezetimibe;candesartan cilexetil and hydrochlorothiazide) in tablets

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Journal of Pharmaceutical Analysis 2013年第2期3卷 118-126页

作者： Tarek S.Belal Hoda G.Daabees magdi m.Abdel-Khalek mohamed S.mahrous mona m.khamis Pharmaceutical Analytical Chemistry Department Faculty of PharmacyUniversity of AlexandriaElmessalah 21521AlexandriaEgypt Pharmaceutical Chemistry Department Faculty of PharmacyUniversity of AlexandriaElmessalah 21521AlexandriaEgypt

A new simple spectrophotometric method was developed for the determination of binary mixtures without prior *** method is based on the generation of ratio spectra of compound X by using a standard spectrum of compound Y as a *** peak to trough amplitudes between two selected wavelengths in the ratio spectra are proportional to concentration of X without interference from *** method was demonstrated by determination of two drug *** first consists of the two antihyperlipidemics：atorvastatin calcium（ATV） and ezetimibe（EZE）,and the second comprises the antihypertensives：candesartan cilexetil（CAN） and hydrochlorothiazide（HCT）.For mixture 1,ATV was determined using 10 μg/mL EZE as the divisor to generate the ratio spectra,and the peak to trough amplitudes between 231 and 276 nm were plotted against ATV ***,by using 10 μg/mL ATV as divisor,the peak to trough amplitudes between 231 and 276 nm were found proportional to EZE *** curves were linear in the range 2.5-40 mg/mL for both *** mixture 2,divisor concentration was 7.5 μg/mL for both *** was determined using its peak to trough amplitudes at 251 and 277 nm,while HCT was estimated using the amplitudes between 251 and 276 *** measured amplitudes were linearly correlated to concentration in the ranges 2.5-50 and 1-30 μg/mL for CAN and HCT,*** proposed spectrophotometric method was validated and successfully applied for the assay of both drug combinations in several laboratory-prepared mixtures and commercial tablets.

关键词： Spectrophotometric analysis Ratio spectra Atorvastatin Ezetimibe Candesartan Hydrochlorothiazide

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Statistical Analysis of a Class of Secure Relay Assisted Cognitive Radio Networks

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China Communications 2018年第12期15卷 174-189页

作者： mona Shokair Waleed Saad Shady m.Ibraheem Electronic and Electrical Comm.Dep. Faculty of Electronic EngineeringMeno.a UniversityEgypt Telecom Egypt Egypt Electrical Engineering Department College of EngineeringShaqra UniversityDawadmiAr RiyadhKingdom of Saudi Arabia

In this paper, the problem of communication security in an underlay wiretap cognitive radio network is addressed and statistically investigated. We rely on a simple dual-hop communication model of decode and forward relay assisted network. Regarding the interference from primary users, interference power and maximum transmit power constraints; this network is subjected to multiple eavesdropping attacks which employ a specific interception strategy. To confound this eavesdropping, proposed selection schemes are exploited that aim at maximizing the minimum of the dual secrecy rates in order to strengthen the physical layer security. moreover, exact and asymptotic closed form expressions are derived for specific performance metrics over independent and identically distributed Rayleigh fading channels. At high signal to interference noise ratio(SINR), tangential system bounds are also derived and discussed. monte Carlo simulation results emphasize our assumption. It is found out that at the full diversity of the system, any additional node that enters the cooperative eavesdropping system becomes significantly of no effect.

关键词： relay selection non-colluding or colluding eavesdroppers outage probability secrecy rate power constraints.

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Genetic Based Approach for Optimal Power and Channel Allocation to Enhance D2D Underlaied Cellular Network Capacity in 5G

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Computers, materials & Continua 2022年第8期72卷 3751-3762页

作者： Ahmed.A.Rosas mona Shokair m.I.Dessouky Department of Electronics and Electrical Communication Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

With the obvious throughput shortage in traditional cellular radio networks,Device-to-Device(D2D)communications has gained a lot of attention to improve the utilization,capacity and channel performance of nextgeneration *** this paper,we study a joint consideration of power and channel allocation based on genetic algorithm as a promising direction to expand the overall network capacity for D2D underlaied cellular *** genetic based algorithm targets allocating more suitable channels to D2D users and finding the optimal transmit powers for all D2D links and cellular users efficiently,aiming to maximize the overall system throughput of D2D underlaied cellular network with minimum interference level,while satisfying the required quality of service QoS of each *** simulation results show that our proposed approach has an advantage in terms of maximizing the overall system utilization than fixed,random,BAT algorithm(BA)and Particle Swarm Optimization(PSO)based power allocation schemes.

关键词： 5G D2D communication spectrum allocation power allocation genetic algorithm optimization BAT-optimization particle swarm optimization

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Biometric Finger Vein Recognition Using Evolutionary Algorithm with Deep Learning

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Computers, materials & Continua 2023年第6期75卷 5659-5674页

作者： mohammad Yamin Tom Gedeon Saleh Bajaba mona m.Abusurrah Department of management Information Systems Faculty of Economics and AdministrationKing Abdulaziz UniversityJeddah21589Saudi Arabia Optus Centre for AI Curtin UniversityPerth6102Australia Department of Business Administration Faculty of Economics and AdministrationKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of management Information Systems College of Business AdministrationTaibah UniversityAl-Madinah42353Saudi Arabia

In recent years,the demand for biometric-based human recog-nition methods has drastically increased to meet the privacy and security *** prints,palm veins,finger veins,fingerprints,hand veins and other anatomic and behavioral features are utilized in the development of different biometric recognition *** the available biometric recognition techniques,Finger Vein Recognition(FVR)is a general technique that analyzes the patterns of finger veins to authenticate the *** Learning(DL)-based techniques have gained immense attention in the recent years,since it accomplishes excellent outcomes in various challenging domains such as computer vision,speech detection and Natural Language Processing(NLP).This technique is a natural fit to overcome the ever-increasing biomet-ric detection problems and cell phone authentication issues in airport security *** current study presents an Automated Biometric Finger Vein Recognition using Evolutionary Algorithm with Deep Learning(ABFVR-EADL)*** presented ABFVR-EADL model aims to accomplish bio-metric recognition using the patterns of the finger ***,the presented ABFVR-EADL model employs the histogram equalization technique to pre-process the input *** feature extraction,the Salp Swarm Algorithm(SSA)with Densely-connected Networks(DenseNet-201)model is exploited,showing the proposed method’s ***,the Deep-Stacked Denoising Autoencoder(DSAE)is utilized for biometric *** proposed ABFVR-EADL method was experimentally validated using the benchmark databases,and the outcomes confirmed the productive performance of the proposed ABFVR-EADL model over other DL models.

关键词： Biometric authentication finger vein recognition deep learning evolutionary algorithm security privacy

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Gas–liquid flow mass transfer in a T-shape microreactor stimulated with 1.7 mHz ultrasound waves

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1143-1152页

作者： mona Akbari masoud Rahimi mahboubeh Faryadi CFD Research Center Chemical Engineering Department Razi University

This paper describes the application of ultrasound waves on hydrodynamics and mass transfer characteristics in the gas–liquid flow in a T-shape microreactor with a diameter of 800 μm. A 1.7 mHz piezoelectric transducer(PZT) was employed to induce the vibration in this microreactor. Liquid side volumetric mass transfer coefficients were measured by physical and chemical methods of CO_2 absorption into water and Na OH solution. The approach of absorption of CO_2 into a 1 mol·L^(-1) Na OH solution was used for analysis of interfacial areas. With the help of a photography system, the fluid flow patterns inside the microreactor were analyzed. The effects of superficial liquid velocity, initial concentration of Na OH, superficial CO_2 gas velocity and length of microreactor on the mass transfer rate were investigated. The comparison between sonicated and plain microreactors(microreactor with and without ultrasound) shows that the ultrasound wave irradiation has a significant effect on kLa and interfacial area at various operational conditions. For the microreactor length of 12 cm, ultrasound waves improved kLa and interfacial area about 21% and 22%, respectively. From this study, it can be concluded that ultrasound wave irradiation in microreactor has a great effect on the mass transfer rate. This study suggests a new enhancement technique to establish high interfacial area and kLa in microreactors.

关键词： Ultrasound waves microreactor Gas–liquid flow mass transfer Absorption

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Dimethylether production on zeolite catalysts activated by Cl^-,F^- and / or ultrasonication

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燃料化学学报 2016年第4期44卷 428-436页

作者： Sameh m.K.Aboul-Fotouh Noha A.K.Aboul-Gheit mona A.Naghmash Chemistry Department Faculty of Education Ain Shams University Roxy Cairo 11757 Egypt Faculty of Science Chemistry Department Northern Border University Arar 91431 Kingdom of Saudi Arabia Egyptian Petroleum Research Institute Cairo 11787 Egypt

The chlorinated and fluorinated zeolite catalysts were prepared by the impregnation of zeolites( H-ZSm-5,H-mOR or H-Y) using two halogen precursors( ammonium chloride and ammonium fluoride) in this study. The influence of ultrasonic irradiation was evaluated for optimizing both halogen precursors for production of dimethylether( DmE) via methanol dehydration in a fixed bed reactor. The catalysts were characterized by SEm,XRD,BET and NH3-TPD. The reaction conditions were temperatures from 100 to 300 ℃ and a WHSV = 15. 9 h-1. All halogenated catalysts showhigher catalytic activities at all reaction temperatures studied. However, the halogenated zeolite catalysts prepared under ultrasonic irradiation showhigher performance for DmE formation. The chlorinated zeolite catalysts show higher activity and selectivity for DmE production than the respective fluorinated versions.

关键词： ultrasonication DmE zeolite Cl^- F^-

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Snapshot multispectral imaging using a diffractive optical network

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Light(Science & Applications) 2023年第5期12卷 789-808页

作者： Deniz mengu Anika Tabassum mona Jarrahi Aydogan Ozcan Electrical and Computer Engineering Department University of CaliforniaLos AngelesCA 90095USA Bioengineering Department University of CaliforniaLos AngelesCA 90095USA California NanoSystems Institute University of CaliforniaLos AngelesCA 90095USA

multispectral imaging has been used for numerous applications in e.g.,environmental monitoring,aerospace,defense,and ***,we present a diffractive optical network-based multispectral imaging system trained using deep learning to create a virtual spectral filter array at the output image *** diffractive multispectral imager performs spatially-coherent imaging over a large spectrum,and at the same time,routes a pre-determined set of spectral channels onto an array of pixels at the output plane,converting a monochrome focal-plane array or image sensor into a multispectral imaging device without any spectral filters or image recovery ***,the spectral responsivity of this diffractive multispectral imager is not sensitive to input polarization *** numerical simulations,we present different diffractive network designs that achieve snapshot multispectral imaging with 4,9 and 16 unique spectral bands within the visible spectrum,based on passive spatially-structured diffractive surfaces,with a compact design that axially spans ~72λ_(m),where λ_(m) is the mean wavelength of the spectral band of ***,we experimentally demonstrate a diffractive multispectral imager based on a 3D-printed diffractive network that creates at its output image plane a spatially repeating virtual spectral filter array with 2×2=4 unique bands at terahertz *** to their compact form factor and computation-free,power-efficient and polarization-insensitive forward operation,diffractive multispectral imagers can be transformative for various imaging and sensing applications and be used at different parts of the electromagnetic spectrum where high-density and wide-area multispectral pixel arrays are not widely available.

关键词： spectrum spectral spatially

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Chitosan/Nanocrystalline Cellulose Biocomposites Based on Date Palm (Phoenix Dactylifera L.) Sheath Fibers

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Journal of Renewable materials 2019年第6期7卷 567-582页

作者： Abeer m.Adel Amira m.El-Shafei Atef A.Ibrahim mona T.Al-Shemy Cellulose and Paper Department National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt Textile Research Division National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt

In this study,nanocrystalline celluloses were used to enhance physical,mechanical and water vapor barrier properties of chitosan films for potential food packaging *** different mineral acids(sulfuric and phosphoric)were used to extract nanocrystalline cellulose from date palm sheath *** influence of cellulose I and cellulose II on the properties of the isolated nanocrystalline celluloses(e.g.,yield,energy and length of intra-and intermolecular hydrogen bonds,and degree of substitution)were studied *** characteristics of chitosan biocomposite film with phosphorylated nanocrystalline cellulose were compared to those with sulfated nanocrystalline *** showed that besides cellulose polymorphism,the ionic ester groups on the surface of nanocrystalline cellulose is one of the factors influencing the physical,chemical,mechanical,and water vapor barrier properties in chitosan/nanocrystalline cellulose biocomposites.

关键词： Biocomposite Cellulose I Cellulose II Nanocrystalline cellulose(NCC) physico-mechanical properties Thermal stability

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Investigation of a mutual interaction force at different pressure amplitudes in sulfuric acid

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Chinese Physics B 2011年第8期20卷 454-459页

作者： Nastaran Rezaee Rasoul Sadighi-Bonabi mona mirheydari Homa Ebrahimi Department of Physics Sharif University of Technology11365-91TehranIran Department of Physics Islamic Azad University Central Tehran BranchTehranIran

This paper investiages the secondary Bjerknes force for two oscillating bubbles in various pressure amplitudes in a concentration of 95% sulfuric acid. The equilibrium radii of the bubbles are assumed to be smaller than 10 μm at a frequency of 37 kHz in various strong driving acoustical fields around 2.0 bars （1 bar=10^5 Pa）. The secondary Bjerknes force is investigated in uncoupled and coupled states between the bubbles, with regard to the quasi-adiabatic model for the bubble interior. It finds that the value of the secondary Bjerknes force depends on the driven pressure of sulfuric acid and its amount would be increased by liquid pressure amplitude enhancement. The results show that the repulsion area of the interaction force would be increased by increasing the driven pressure because of nonlinear oscillation of bubbles.

关键词： multi-bubble sonoluminescence secondary Bjerknes force coupled and uncoupled state,nonlinear oscillation

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Effect of the Si/Al ratio of HZSm-5 zeolite on the production of dimethyl ether before and after ultrasonication

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燃料化学学报 2017年第5期45卷 581-588页

作者： Sameh m.K.Aboul-Fotouh Laila I.Ali mona A.Naghmash Noha A.K.Aboul-Gheit Chemistry Department Faculty of ScienceNorthern Boder UniversityArar 91431Kingdom of Saudi Arabia Chemistry Department Faculty of EducationAin Shams UniversityRoxyCairo 11757Egypt Egyptian Petroleum Research Institute Nasr CityCairo 11787Egypt

A series of as-synthesized HZSm-5 zeolites with different Si/Al ratios(25,90,120,240 and 400)were post-treated by ultrasonication for an optimum time of 60 *** morphology,acidity and textural properties of HZSm-5 were characterized with XRD,SEm,N_2 adsorption and NH3-TPD *** catalytic performance was evaluated by dehydration of methanol to dimethyl ether(DmE),which is a promising gaseous automotive fuel in *** was found that the Si/Al ratio of HZSm-5 had considerable impacts on its catalytic performance for dehydration of methanol to *** activity increased with decreasing Si/Al ratio from 400 to *** of HZSm-5 could significantly improve its catalytic performance.

关键词： Ultrasonication-HZSm-5-dimethyl ether-Si/Al 比率

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