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Ballistic design and testing of a composite armour reinforced by CNTs suitable for armoured vehicles

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Defence Technology（防务技术） 2024年第2期32卷 173-195页

作者： Evangelos ch.Tsirogiannis Evangelos Daskalakis mohamed h.hassan Abdalla m.Omar Paulo Bartolo EODh SA Research and Development DepartmentLakkoma Chalkidikis63080Greece School of mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK Singapore Centre for 3D Printing School of Mechanical and Aerospace EngineeringNanyang Technological University639798Singapore

This paper is investigating the use of composite armour reinforced by nanomaterials, for the protection of light armoured(LAV) and medium armoured military vehicles(mAV), and the interaction between the composite materials and high-performance ballistic projectiles. Four armour materials, consisted of front hybrid fibre reinforced polymer cover layer, ceramic strike-face, fibre reinforced polymer intermediate layer and the metal matrix composite reinforced backplate, were manufactured and assembled by adhesive technology. The proposed laminated protection system is suitable for armoured ground vehicles;however, it could be used as armour on ground, air and naval platforms. The design of the protection system, including material selection and thickness, was elaborated depending on the performance requirements of Level 4 + STANAG 4569 military standard(projectile 14.5 mm × 114 mm API B32) and especially on a design philosophy which is analysed with the specifications. The backplate of this new composite is a hybrid material of metal matrix Composite(mmC) reinforced with carbon nanotubes(CNTs), manufactured with the use of powder metallurgy technique. The composite backplate material was morphologically, mechanically and chemically analysed. Results show that all plates are presenting high mechanical properties and ballistic characteristics, compared to commonly used armour plates. Real military ballistic tests according to AEP-STANAG 4569 were carried out for the total composite armour systems. After the ballistic tests, AA2024-CNT3 showed the best protection results, compared with the other plates(AA2024-CNT1 and AA2024-CNT2), with the projectile being unable to fully penetrate the composite plate.

关键词： Passive armour protection Protective armour Ballistic performance hybrid composites Vehicle protection

Dysprosium oxide,alumina,and graphene oxide reinforced polycaprolactone thin films:Thermal stability,morphology,and cell viability

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Journal of Rare Earths 2024年第7期42卷 1337-1343,I0005页

作者： mohamed Tharwat elabbasy mohamed R.Atteya mai A.Samak mousa Abdelrahman Tahani Almahmoud m.A.el-morsy A.A.menazea m.F.h.Abd el-Kader Department of Public health College of Public Health and Health InformaticsUniversity of Ha'ilHa'il2440Saudi Arabia Food Control Department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Department of Physical Therapy College of Applied Medical SciencesUniversity of Ha'ilHa'ilSaudi Arabia Department of histology and Cell Biology Faculty of MedicineZagazig UniversityZagazig44519Egypt College of Nursing University of Ha'ilHa'ilSaudi Arabia College of Science and humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics Department Faculty of ScienceUniversity of DamiettaNew Damietta34517Egypt Spectroscopy Department Physics Research InstituteNational Research CentreDokki12622GizaEgypt Biophysics Department Faculty of ScienceCairo UniversityGizaEgypt

Developing a biomaterial for wound healing applications is still a ***,dysprosium oxide(Dy_(2)O_(3)),aluminum oxide(Al_(2)O_(3)),and graphene oxide(GO)were embedded in cast films based on polycaprolactone(PCL)to be examined for wound dressing *** techniques were used to characterize the fabricated films including X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),Raman,and scanning electron microscopy(SEm),besides their biological *** thermogravimetric analysis(TGA)exhibits high thermal stability as the scaffold weight decreases slightly to 98.6%after raising the temperature from room temperature to 280℃.The cell viability was investigated and it is shown that the viable cells grow up to approximately 93%at 75μg/***,the cell attachment shows excellent behavior as the cells attach on most of the surface of the modified PCL which shows high biocompatibility.

关键词： Wound healing Polycaprolactone Dy_(2)O_(3) Al_(2)O_(3) Biocompatible Rare earths

Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt

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Journal of Arid Land 2024年第7期16卷 1000-1021,I0002-I0044页

作者： Asmaa S ABO hATAB Yassin m AL-SODANY Kamal h ShALTOUT Soliman A hAROUN mohamed m el-KhALAFY Botany and microbiology Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33511Egypt Botany Department Faculty of ScienceTanta UniversityTanta 31527Egypt

Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes morocco, mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the mediterranean and Irano-Turanian regions included in the holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic sp

关键词： endemism phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)

A statistical approach to enhance the productivity of Streptomyces baarensis mh-133 for bioactive compounds

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Synthetic and Systems Biotechnology 2024年第2期9卷 196-208页

作者： mohamed h.Kalaba Gamal m.el-Sherbiny Osama m.Darwesh Saad A.moghannem Botany and microbiology Department Faculty of Science(Boys)Al-Azhar UniversityCairo 11884Egypt Agricultural microbiology Department National Research CentreDokkiCairoEgypt

The goal of this study was to use statistical optimization to change the nutritional and environmental conditions so that Streptomyces baarensis mh-133 could make more active *** trials were used to screen for critical variables influencing productivity using the Placket-Burman Design *** mh-133 is significantly influenced by elicitation,yeast extract,inoculum size,and incubation period in terms of antibacterial activity.A total of 27 experimental trials with various combinations of these factors were used to carry out the response surface technique using the Box-Behnken *** analyses revealed that the model was highly significant(ph a lack-of-fit of 0.212 and a coefficient determination(R2)of ***,the model predicted that the response as inhibition zone diameter would reach a value of 27 *** optimal conditions,*** mh-133 produced 18.0 g of crude extract to each 35L and was purified with column *** active fraction exhibiting antibacterial activity was characterized using spectroscopic *** mIC and mBC values varied between 37.5 and 300μg/ml and 75 and 300μg/ml,*** conclusion,the biostatistical optimization of the active fraction critical variables,including environmental and nutritional conditions,enhances the production of bioactive molecules by Streptomyces species.

关键词： S.baarensis mh-133 Placket-Burman designBox-Behnken design ESKAPE Antibacterial activity

A hybrid machine-learning model for solar irradiance forecasting

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Clean Energy 2024年第1期8卷 100-110页

作者： Ameera m.Almarzooqi maher maalouf Tarek h.m.el-Fouly Vasileios E.Katzourakis mohamed S.el moursi Constantinos V.chrysikopoulos Department of Industrial and Systems Engineering Khalifa UniversityAbu DhabiPO Box 127788UAE electrical Engineering and Computer Science Department Khalifa University Abu DhabiUAE Department of Civil Infrastructure and Environmental Engineering Khalifa UniversityAbu DhabiPO Box 127788UAE School of chemical and Environmental Engineering Technical University of CreteChaniaGreece

Nowcasting and forecasting solar irradiance are vital for the optimal prediction of grid-connected solar photovoltaic(PV)power *** plants face operational challenges and scheduling dispatch difficulties due to the fluctuating nature of their power *** the generation capacity within the electric grid increases,accurately predicting this output becomes increasingly essential,especially given the random and non-linear characteristics of solar irradiance under variable weather *** study presents a novel prediction method for solar irradiance,which is directly in correlation with PV power output,targeting both short-term and medium-term forecast *** proposed hybrid framework employs a fast trainable statistical learning technique based on the truncated-regularized kernel ridge regression *** proposed method excels in forecasting solar irradiance,especially during highly intermittent weather periods.A key strength of our model is the incorporation of multiple historical weather parameters as inputs to generate accurate predictions of future solar irradiance values in its scalable *** evaluated the performance of our model using data sets from both cloudy and sunny days in Seattle and medford,USA and compared it against three forecasting models:persistence,modified 24-hour persistence and least *** on three widely accepted statistical performance metrics(root mean squared error,mean absolute error and coefficient of determination),our hybrid model demonstrated superior predictive accuracy in varying weather conditions and forecast horizons.

关键词： solar power generation kernel ridge regression hybrid model forecasting

Large magnetocaloric effect and magnetic properties of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： m.Lassri m.Sajieddine A.elouafi A.el hachmi S.el Ouahbi R.moubah Laboratory of Energy and materials Engineering (LGEm) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) Institute of Applied Physics (IAP)-School of Industrial management (EmINES) Mohammed Ⅵ Polytechnic University National School of Applied Sciences (ENSA) University of Sultan Moulay Slimane Laboratory of mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on matter and Instrumentation (LRmI) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced materials and Thermic (LPmAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPS）.It is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,which is close to the theoretical value ■.The magnetic entropy change(-ΔSm),was determined by em ploying the thermodynam ic maxwell's *** μ0h=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-ΔSmand RCP show that the EuRhO3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： Cryogenic magnetic refrigeration magnetic properties magnetocaloric effect Rare earths X-ray photoelectron spectroscopy

Effect of nutrition-related infodemics and social media on maternal experience: A nationwide survey in a low/middle income country

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World Journal of Clinical Pediatrics 2024年第1期13卷 93-106页

作者： marwa m Zein Noha Arafa mortada h F el-Shabrawi Nehal mohammed el-Koofy Department of Public health and Community medicine Cairo UniversityCairo 515211Egypt Department of Pediatric Endocrinology and Diabetes Children's HospitalKasralainy Medical SchoolCairo UniversityCairo 515211Egypt Department of Pediatrics Cairo UniversityCairo 12411Egypt Department of Pediatrics The Children's HospitalCairo UniversityCairo 12411Egypt

BACKGROUND Undernutrition is a crucial cause of morbidity and mortality among children in low-or middle-income countries(LmICs).A better understanding of maternal general healthy nutrition knowledge,as well as misbeliefs,is highly essential,especially in such *** the current era of infodemics,it is very strenuous for mothers to select not only the right source for maternal nutrition information but the correct information as *** To assess maternal healthy nutritional knowledge and nutrition-related misbeliefs and misinformation in an LmIC,and to determine the sources of such information and their assessment *** This cross-sectional analytical observational study enrolled 5148 randomly selected Egyptian mothers who had one or more children less than 15 years *** data were collected through online questionnaire forms:One was for the general nutrition knowledge assessment,and the other was for the nutritional myth *** of information and ways of evaluating internet sources using the Currency,Relevance,Authority,Accuracy,and Purpose test were additionally *** The mean general nutrition knowledge score was 29±9,with a percent score of 70.8%±12.1%(total score:41).The median myth score was 9(interquartile range:6,12;total score:18).The primary sources of nutrition knowledge for the enrolled mothers were social media platforms(55%).half of the mothers managed information for currency and authority,except for considering the author's contact *** than 60%regularly checked information for accuracy and *** mothers with significant nutrition knowledge checked periodically for the author's contact information(P=0.012).The nutrition myth score was significantly lower among mothers who periodically checked the evidence of the information(P=0.016).mothers dependent on their healthcare providers as the primary source of their general nutritional knowledge were less likely to hold myths by 13%(P=0.044).however,usi

关键词： Nutrition Infodemics maternal knowledge myth Low/middle income country

Surface morphology and cell viability of samarium(Ⅲ) oxide/chromium(Ⅲ) oxide/graphene oxide/polycaprolactone targeting wound dressing

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Journal of Rare Earths 2024年第3期42卷 555-561,I0005页

作者： muteb h.Alshammari Ahmed Onayzan Alshammari mohamed Tharwat elabbasy Rafat Zreiq Faris mohammed Albati m.A.el-morsy A.A.menazea Department of health Informatics College of Public Health and Health InformaticsUniversity of Ha'ilHa'ilSaudi Arabia Department of Surgery College of MedicineUniversity of Ha'ilHa'ilSaudi Arabia Department of Public health College of Public Health and HealthInformaticsHalUniversityHa'il2440Saudi Arabi Food Control Department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Applied Science Research Center Applied Science Private UniversityAmman541350Jordan College of Shariah and Law Ha'il UniversityHa'il2440Saudi Arabia College of Science and humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics Department Faculty of ScienceUniversity of DamittaNew Damietta34517.Egyp Spectroscopy Department Physics Research InstituteNational Research CentreDokki12622GizaEgypt

Combinations of metal and lanthanide oxides have been done through casted films for potential medical applications. In this regard, samarium(Ⅲ) oxide/chromium(Ⅲ) oxide/graphene oxide(GO)/polycaprolactone(PCL) based films nano-composites(NCs) were fabricated, pointing their utilization as a biological scaffold for wound dressing purposes. Also, samarium(Ⅲ) oxide and chromium(Ⅲ) oxide have been merged as promising optical constituents due to their unique optical behavior. The structural and compositional examination of the studied NCs was executed by X-ray diffraction(XRD), Raman, and field emission scanning electron microscopy(FESEm). The Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL NC exhibits a surface with a lower roughness degree owing to the presence of GO. Cr_(2)O_(3)shows size reduction upon GO insertion to reach 1.2 μm as the average grain size, whilst Sm_(2)O_(3)records an average grain size of less than 1 μm. As well, the polymeric nano-compositions exhibit variation in contact angle values that hit 29.76°± 3.52°for Sm_(2)O_(3)/PCL, and 48.62°± 1.37°for Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL as the second lowest contact angle. The optical behavior contributes to absorption edge relocation along the x-axis from 1.7 eV for pure PCL, to 2.65 eV for Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL. Regarding biological responses, the cell exposed to 2.5 μg/m L of Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL shows cell viability of 119.31%, while 5 μg/m L hits 99.6%. Additionally, the resulting cell attachment micrographs show layers of fibroblast tissue, besides the proliferation and growth of cultivated cells. Thus, the Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL scaffold provides 3D proliferation of fibroblast cells endorsing the wound healing process.

关键词： Wound healing Wound dressing Polycaprolactone Sm_(2)O_(3) Cr_(2)O_(3) Rare earths

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