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Doping effect of SrZrO_(3) on KNLN ceramics structure and their dielectric properties

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Journal of Advanced Dielectrics 2018年第5期8卷 28-34页

作者： Emad Ewais Ragab Mahani samy mostafa Adel Ahmedx Refractory and Ceramic Materials Division(RCMD)Central Metallurgical R&D Institute P.O.87 Helwan 11421 CairoEgypt Microwave Physics and Dielectrics Department National Research Centre 33 EL Bohouth st.(former EL Tahrirst.)P.O.12622 GizaEgypt Tabbin Institute for Metallurgical Studies(TIMS)P.O.109 Helwan 11421 CairoEgypt Chemistry Department Helwan University HelwanCairoEgypt

In this work,lead-free systems;(1-x)(K_(0.465)Na_(0.465)Li_(0.07))NbO_(3)–xSrZrO_(3)(x=0,0.005,0.050,0.095 and 0.14)were synthesized by the conventional solid-state reaction ***,SEM,densification parameter as well as dielectric parameters of the obtained KNLN ceramics were *** analysis showed the formation of orthorhombic perovskite structure in all investigated ***_(3)(SZ)inhibited the grain growth and increased the distribution of grains uniformly in the micro*** addition,SZ changed the crystalline system of KNLN ceramics *** a consequence,the permittivity,dielectric loss as well as AC conductivity decreased *** ceramics of x=0.005 are characterized by low conductivity(10-10 S/cm),low dielectric loss(0.005)and relatively high permittivity(34).They can be useful for the electrical capacitors fabrication and filtering out noise from signals in resonant *** frequencies lower than 105 Hz,DC conductivity and separation of the charges at the interfaces were found to dominate the electrical behavior of ceramics,whereas at higher frequencies,a faster or dipole polarization may become more dominated.A broad peak has been observed in the imaginary part of electric modulus revealing to the non-Debye dielectric relaxation *** mechanical tunneling(QMT)was found to be the most suitable to characterize the electrical conduction mechanism in the ceramic compounds.

关键词： Lead-free ceramics KNLN dielectric properties.

Global Solutions to Nonconvex Problems by Evolution of Hamilton-Jacobi PDEs

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Communications on Applied Mathematics and Computation 2024年第2期6卷 790-810页

作者： Howard Heaton samy Wu Fung Stanley Osher Typal Research Typal LLCLos AngelesUSA Department of Applied Mathematics and Statistics Colorado School of MinesGoldenUSA Department Mathematics UCLALos AngelesUSA

Computing tasks may often be posed as optimization *** objective functions for real-world scenarios are often nonconvex and/or ***-of-the-art methods for solving these problems typically only guarantee convergence to local *** work presents Hamilton-Jacobi-based Moreau adaptive descent(HJ-MAD),a zero-order algorithm with guaranteed convergence to global minima,assuming continuity of the objective *** core idea is to compute gradients of the Moreau envelope of the objective(which is"piece-wise convex")with adaptive smoothing *** of the Moreau envelope(i.e.,proximal operators)are approximated via the Hopf-Lax formula for the viscous Hamilton-Jacobi *** numerical examples illustrate global convergence.

关键词： Global optimization Moreau envelope Hamilton-Jacobi Hopf-Lax-Cole-Hopf Proximals Zero-order optimization

Exploring Sequential Feature Selection in Deep Bi-LSTM Models for Speech Emotion Recognition

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Computers, Materials & Continua 2024年第2期78卷 2689-2719页

作者： Fatma Harby Mansor Alohali Adel Thaljaoui Amira samy Talaat Computer Science Department Future Academy-Higher Future Institute for Specialized Technological StudiesCairo12622Egypt Department of Computer Science and Information College of Science at Zulfi Majmaah UniversityP.O.Box 66Al-Majmaah11952Saudi Arabia Preparatory Institute for Engineering Studies of Gafsa ZarrougGafsa2112Tunisia Computers and Systems Department Electronics Research InstituteCairo12622Egypt

Machine Learning(ML)algorithms play a pivotal role in Speech Emotion Recognition(SER),although they encounter a formidable obstacle in accurately discerning a speaker’s emotional *** examination of the emotional states of speakers holds significant importance in a range of real-time applications,including but not limited to virtual reality,human-robot interaction,emergency centers,and human behavior *** identifying emotions in the SER process relies on extracting relevant information from audio *** studies on SER have predominantly utilized short-time characteristics such as Mel Frequency Cepstral Coefficients(MFCCs)due to their ability to capture the periodic nature of audio signals *** these traits may improve their ability to perceive and interpret emotional depictions appropriately,MFCCS has some *** this study aims to tackle the aforementioned issue by systematically picking multiple audio cues,enhancing the classifier model’s efficacy in accurately discerning human *** utilized dataset is taken from the EMO-DB database,preprocessing input speech is done using a 2D Convolution Neural Network(CNN)involves applying convolutional operations to spectrograms as they afford a visual representation of the way the audio signal frequency content changes over *** next step is the spectrogram data normalization which is crucial for Neural Network(NN)training as it aids in faster *** the five auditory features MFCCs,Chroma,Mel-Spectrogram,Contrast,and Tonnetz are extracted from the spectrogram *** attitude of feature selection is to retain only dominant features by excluding the irrelevant *** this paper,the Sequential Forward Selection(SFS)and Sequential Backward Selection(SBS)techniques were employed for multiple audio cues features ***,the feature sets composed from the hybrid feature extraction methods are fed into the deep Bidirectional Long Short

关键词： Artificial intelligence application multi features sequential selection speech emotion recognition deep Bi-LSTM

Solute transport and geochemical modeling of the coastal quaternary aquifer, Delta Dahab Basin, South Sinai, Egypt

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Acta Geochimica 2024年第1期43卷 16-39页

作者： Amira samy Mustafa Eissa Seham Shahen Moustafa M.Said Rabab M.Abou-shahaba Division of Water Resources and Arid Land Department of HydrogeochemistryDesert Research CenterCairoEgypt Egypt Desalination Research Center of Excellence Desert Research CenterCairoEgypt Center for Water Supply Studies S&E-Physical&Environmental SciencesTexas A&M University Corpus ChristiCorpus ChristiUSA Department of Chemistry Faculty of Science(Girls)Al-Azhar UniversityYousef Abbas StrNasr CityP.O.Box:11754CairoEgypt

The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWMI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWMI 1>) and other samples mixed with Seawater(SWMI < 1). The isotopic composition of groundwater for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)O and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems.

关键词： Groundwater geochemistry Seawater intrusion Solute transport SEAWAT

Novel Sustainable Cellulose Acetate Based Biosensor for Glucose Detection

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Journal of Renewable Materials 2024年第2期12卷 369-380页

作者： M.F.Elkady E.M.El-Sayed Mahmoud samy Omneya A.Koriem H.Shokry Hassan Chemical and Petrochemical Engineering Department Egypt-Japan University of Science and TechnologyNew Borg El-ArabAlexandriaEgypt Fabrication Technology Research Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-ArabAlexandria21934Egypt Department of Public Works Engineering Faculty of EngineeringMansoura UniversityMansoura35516Egypt Environmental Engineering Department Egypt-Japan University of Science and TechnologyNew Borg El-ArabAlexandriaEgypt Electronic Materials Research Department Advanced Technology and NewMaterials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-ArabAlexandria21934Egypt

In this study,green zinc oxide(ZnO)/polypyrrole(Ppy)/cellulose acetate(CA)film has been synthesized via solvent *** film was used as supporting material for glucose oxidase(GOx)to sensitize a glucose *** nanoparticles have been prepared via the green route using olive leaves extract as a ***/Ppy nanocomposite has been synthesized by a simple in-situ chemical oxidative polymerization of pyrrole(Py)monomer using ferric chloride(FeCl3)as an oxidizing *** produced materials and the composite films were characterized using X-ray diffraction analysis(XRD),scanning electron microscope(SEM),Fourier transform infrared(FTIR)and thermogravimetric analysis(TGA).Glucose oxidase was successfully immobilized on the surface of the prepared film and then ZnO/Ppy/CA/GOx composite was sputtered with platinum electrode for the current determination at different initial concentrations of *** measurements proved the suitability and the high sensitivity of the constructed biosensor for the detection of glucose levels in different *** performance of the prepared biosensor has been assessed by measuring and comparing glucose concentrations up to 800 *** results affirmed the reliability of the developed biosensor towards real samples which suggests the wide-scale application of the proposed biosensor.

关键词： Biosensors composite films glucose polypyrrole green ZnO cellulose acetate

Effect of Single- versus Double-Layer Uterine Closure during Caesarean Section on Niche Formation and Menstrual Irregularity

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Open Journal of Obstetrics and Gynecology 2024年第1期14卷 57-68页

作者： Mohamed samy Esraa Hussein Fouad Ghoneimy Walid Hitler Department of Obstetrics and Gynaecology Faculty of Medicine Ain Shams University Cairo Egypt

Background: The myometrium at the location of the CS (caesarean section) scars, also known as residual myometrium thickness (RMT), is larger after a double-layer uterine closure procedure than following a single-layer one. It may lessen the formation of a niche that is the myometrium’s disruption at the location of the scar of the uterus. Gynecological manifestations, obstetric problems in a future pregnancy and birth, and maybe subfertility are linked to thin RMT and a niche. Objective: To ascertain if double-layer unlocked closure of the uterus is better than single-layer one in terms of post-menstrual spotting and niche development following a first CS. Patients and Methods: In this randomized clinical study, 287 patients were evaluated for qualifying. Of all eligible individuals, 57 patients were excluded from the study based on the inclusion criteria. Results: The variation in ages, gestational age, body mass index (BMI), and cesarean section indications between the two assigned groups is statistically insignificant. However, postmenstrual spotting was statistically significantly more common in single-layer group compared to in double-group. The current study revealed ultrasound findings suggestive of niche formation was statistically significantly more common in single-layer group compared to in double-layer group. Conclusion: As evident from the current study, it demonstrates the advantages of double-layer unlocked closure of the uterus over single-layer one in terms of post-menstrual spotting and niche development following first-time cs. Thus, we deduced that fewer niches are formed, and fewer menstrual spotting occurs in the presence of double unlocked layers closure. To ascertain the impact of uterus closure method on post-operative niche development and the risk of obstetrics and gynaecological problems, further prospective trials with extended follow-up periods are required.

关键词： Single-Layer Double Caesarean Section Residual Myometrium Thickness

Rhizobium Inoculation and Micronutrient Addition Influence the Growth,Yield,Quality and Nutrient Uptake of Garden Peas(Pisum sativum L.)

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 901-922页

作者： MdAbdul Quddus MdAtaur Rahman Razu Ahmed Mohammad Eyakub Ali Khokan Kumer Sarker MdAlamgir Siddiky Mohibur Rahman Lamya Ahmed Alkeridis samy Sayed Ahmed Gaber Akbar Hossain Horticulture Research Centre Bangladesh Agricultural Research InstituteGazipur1701Bangladesh Soil Science Division Bangladesh Agricultural Research InstituteGazipur1701Bangladesh Irrigation and Water Management Division Bangladesh Agricultural Research InstituteGazipur1701Bangladesh Regional Agricultural Research Station Bangladesh Agricultural Research InstituteCumilla3500Bangladesh Department of Biology College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Science and Technology University College‑RanyahTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Economic Entomology and Pesticides Faculty of AgricultureCairo UniversityGiza12613Egypt Department of Genetics Faculty of AgricultureCairo UniversityGiza12613Egypt Department of Biology College of ScienceTaif UniversityTaif21944Saudi Arabia Division of Soil Science Bangladesh Wheat and Maize Research InstituteDinajpur5200Bangladesh

Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient ***,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity and quality of garden peas,since this management for garden peas is neglected in ***,the present study was made to assess the effectiveness of rhizobium inoculant singly or in combination with the micronutrients(i.e.,Zn,B,and Mo)on growth,yield,nutrient uptake,and quality of garden *** were:T_(1)=Control,T_(2)=Rhizobium inoculation at 50 g/kg seed,T_(3)=T_(2)+Zn_(3)Mo1,T_(4)=T_(2)+B_(2)Mo1,T_(5)=T_(2)+Zn_(3)B_(2),T_(6)=T_(2)+Zn_(3)B_(2)Mo1 and T_(7)=Zn_(3)B_(2)*** treatments were arranged in a randomized complete block design and repeated all treatments in three *** application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)with inoculation of Rhizobium at 50 g kg^(−1)seed(T_(6))facilitated to increase of 44.8%in the green pod and 29.7%seed yield over *** same treatment contributed to attaining the maximum nodulation(25.3 plant^(−1)),Vitamin C(43.5 mg 100 g^(−1)),protein content(22.2%),and nutrient uptake as well as accumulation in garden *** all treatment combinations,treatment T_(6)was found superior to others based on microbial activities,soil fertility,and *** results of the study found that the application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)in combination with Rhizobium inoculation(50 g kg^(−1)seed)can improve the yield and quality of garden *** results of the study have the potential for the areas,where there is no use of Rhizobium inoculant or Zn,B,and Mo fertilizer for cultivation of garden pea.

关键词： Nodulation nutrient content Pisum sativum L. profitability rhizobium Zn B Mo

Evaluation of the nutritional value of Artemia nauplii for European seabass(Dicentrarchus labrax L.)larvae

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Aquaculture and Fisheries 2024年第1期9卷 78-84页

作者： Alaa A.El-Dahhar Rashwan S.Rashwan samy Y.EL-Zaeem Shaimaa A.Shahin Mona M.Mourad Mohammed F.El Basuini Animal and Fish Production Department Faculty of Agriculture-Saba BashaAlexandria UniversityAlexandria21526Egypt National Institute of Oceanography and Fisheries(NIOF) Cairo11562Egypt Department of Animal Production Faculty of AgricultureTanta UniversityTanta31527Egypt Faculty of Desert Agriculture King Salman International UniversitySouth Sinai46618Egypt

Adapted European seabass(Dicentrarchus labrax L.)larvae at 25 days post-hatching(dph)with a primary weight and length of 23 mg and 9.92 mm,start the weaning up to 46 dph using the weaning micro-diet(54%crude protein from fish meal,powder milk,and poultry egg)concurrently with Artemia enriched with fortification emulsions(0.6 g/L)of DHA selco®as a control group(DHAS)or Fish oil+20%Vitamin C(FOVC),or Fish oil+20%Vitamin E(FOVE),or Fish oil+10%Vit.C+10%Vit.E(FOCE),or Fish oil only(FO).At 46 dph,groups of larvae fed enriched Artemia with DHAS and FOVE exhibited the highest final body weight,weight gain,average daily gain,specific growth rate,feed intake,protein efficiency ratio,and survival%as well as the lowest feed conversion ***,larvae in FOVC displayed the lowest final body weight,total length,weight gain,average daily gain,specific growth rate,feed intake,protein efficiency ratio,and survival%as well as the highest feed conversion *** histological assessment exhibited no pathological alteration as well as an improvement in the structure with DHAS,FOVE,FOVC,and FOCE co-additives compared to *** peroxidase enzyme(GPx)recorded the highest rates(P<0.05)in groups fed Artemia supplemented with DHAS and FOVE followed by FOCE and *** the lowest record for GPx activity was noted in the FO *** conclusion,Using augmented Artemia nauplii with fish oil+vitamin E in single or in companion with vitamin C as cheap antioxidants support *** larval growth,survival,and antioxidant efficacy during the critical weaning period.

关键词： European seabass Gastrointestinal histology Antioxidants Vitamin C Vitamin E DHA

Palaeogene Sandstones of the Manika Plateau in Kolwezi (DR Congo): Sedimentological and Geochemical Characterization, Provenance, Palaeoalteration and Tectonic Context

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Open Journal of Geology 2024年第7期14卷 705-722页

作者： Pierre T. Mashala Faidance Mashauri samy M. Malango Christian K. Mulopwe Department of Geology University of Lubumbashi Haut-Katanga DR Congo Department of Geology University of Ul Haut-Ul DR Congo Department of Geology and Technology University of Kolwezi Lualaba DR Congo

This work presents a study of the Paleogene sandstones of the Manika plateau in Kolwezi, DR Congo. These sandstones belong to the “Grès polymorphes” group, which together with the overlying “Sables ocre” makes up the Kalahari Supergroup. Sedimentological and geochemical analyses have enabled us to characterize these sandstones and determine their origin, the conditions of their formation and the tectonic context in which they were developed. The results show that the sandstones are quartz arenites with a high level of mineralogical, textural and chemical maturity. They are recycled sandstones, formed in an intracratonic sedimentary basin, in the context of a passive continental margin, after a long fluvial transport of sediments. These sandstones initially come from intense alteration of magmatic rocks with felsic composition, mainly tonalite-trondhjemite-granodiorite (TTG) complexes, in hot, humid palaeoclimatic conditions and oxidizing environments.

关键词： Sandstone Sedimentology Geochemistry Palaeoalteration Tectonic Context Manika Plateau DR Congo