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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.m.FEIZABAD m.h.YAs Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

Impact of carbimazole combined with vitamin E on testicular injury induced by experimental hyperthyroidism in adult albino rats:oxidative/inflammatory/apoptotic pathways

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Asian Journal of Andrology 2024年第4期26卷 396-401页

作者： Ramadan s hussein moustafa m Eyada Rashad m mostafa samah m Elaidy shereen h Elsayed hany m saad Department of Dermatology College of Medicine Prince Sattam Bin Abdulaziz UniversityAl-Kharj 16242Saudi Arabia Department of Dermatology Andrology and STDsAssiut Police HospitalAssiut 71525Egypt Department of Dermatology Venereology and AndrologyFaculty of MedicineSuez Canal UniversityIsmailia 41522Egypt Department of Andrology and sexology Faculty of MedicineSuez Canal UniversityIsmailia 41511Egypt Department of Clinical Pharmacology Faculty of MedicineSuez Canal UniversityIsmailia 41511Egypt Department of Rehabilitation sciences Faculty of Health and Rehabilitation SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh 12271Saudi Arabia.

Thyroid hormones play essential roles in spermatogenesis,but their effects on infertile males remain poorly *** study aimed to evaluate the impact of combining carbimazole(CBZ)with vitamin E(VE)on testicular injury induced by experimental hyperthyroidism in adult albino rats,focusing on oxidative,inflammatory,and apoptotic *** this experimental study,64 adult male albino Wistar rats were divided into eight groups:Group I(control-untreated),Group II(CBZ-control),Group III(VE-control),Group IV(CBZ+VE-control),Group V(levothyroxine-induced testicular injury),Group VI(levothyroxine+CBZ-treated),Group VII(levothyroxine+VE-treated),and Group VIII(levothyroxine+CBZ+VE-treated).The study was conducted in the Faculty of medicine,suez Canal University(Ismailia,Egypt).After cervical decapitation,both testes and epididymis were examined histopathologically and *** differences were observed among groups concerning malondialdehyde(mDA),glutathione(Gsh),superoxide dismutase(sOD),and catalase(CAT;all Pmerase chain reaction analysis showed significant differences in tumor necrosis factor-α(TNF-α),interleukin-10(IL-10),Bcl-2-associated X protein(BAX),B-cell lymphoma 2 protein(Bcl2),p53,Caspase-3,Caspase-8,Caspase-9,and nuclear factor-kappa B(NF-κB)mRNA levels(all Phyperthyroid group treated with CBZ alone(Group VI)exhibited testicular side effects,affecting seminiferous tubules and ***,the Group VIII showed improved spermatogenesis and a decrease in testicular side *** addition of VE to the treatment of hyperthyroid rats with CBZ reduced testicular side effects and seminiferous tubular affection when potentially improving *** research is needed to elucidate the underlying mechanisms fully.

关键词： antithyroid drugs testicular injury thyroid gland vitamin E

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)snO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： m.K.h.hamad Nidal Dwaikat m.h.A.mhareb m.I.sayyed R.m.hamad Y.s.m.Alajerami m.A.Almessiere Gameel saleh Ahmad hussein Alomari K.A.Ziq Department of Basic sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)snO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOm computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)snO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding mass stopping power Rare earths

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： semiconductor TiO_(2) Rare earths Congo red methylene blue solar spectrum Photodegradation

multiple scales method for analyzing a forced damped rotational pendulum oscillatorwithgallows

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Communications in Theoretical Physics 2024年第5期76卷 58-67页

作者： haifa A Alyousef Alvaro h salas B m Alotaibi s A El-Tantawy Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of mathematics and statistics Universidad Nacional de ColombiaFIZMAKO Research GroupColombia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversityAl-Baha 1988Saudi Arabia

This study reports the analytical solution for a generalized rotational pendulum system with gallows and periodic excited *** multiple scales method(msm)is applied to solve the proposed *** types of rotational pendulum oscillators are studied and talked about in *** include the forced damped rotating pendulum oscillator with gallows,the damped standard simple pendulum oscillator,and the damped rotating pendulum oscillator without *** msm first-order approximations for all the cases mentioned are derived in *** obtained results are illustrated with concrete numerical *** first-order msm approximations are compared to the fourth-order Runge-Kutta(RK4)numerical ***,the maximum error is estimated for the first-order approximations obtained through the msm,compared to the numerical approximations obtained by the RK4 ***,we conducted a comparative analysis of the outcomes obtained by the used method(msm)and he-msm to ascertain their respective levels of *** proposed method can be applied to analyze many strong nonlinear oscillatory equations.

关键词： rotational pendulum system multiple scales method approximate solution damped oscillations forced pendulum with gallows he-multiple scales method

sodium nitroprusside as a signal molecule for up-regulating membrane characteristics,antioxidant defense system to improve flax productivity under water stress

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Oil Crop science 2024年第3期9卷 160-169页

作者： N.m.Al-Ashkar B.A.Bakry h.m.s.El-Bassiouny m.m.s.Abdallah m.s.sadak Botany Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt Field Crops Research Department Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt

Water stress is a critical environmental adversity that significantly impacts the growth,development,and yield of flax *** this study,flax seeds were cultivated under different water irrigation requirements(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(NO)donor sodium nitroprusside(sNP)as foliar treatments at concentrations of 0.0 mmol/L,0.5 mmol/L,1.0 mmol/L,and 2.0 mmol/*** stress led to a significant decrease in plant growth,photosynthetic pigments,yield components such as oil and total carbohydrate *** also resulted in an increase in leaf h2O2 production,lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase,superoxide dismutase,and nitrate reductase ***,foliar application of sNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species *** use of sNP also decreased h_(2)O_(2) accumulation levels,lipid peroxidation levels,and improved membrane *** treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.

关键词： Flax Fatty acid sodium nitroprusside Antioxidant enzymes Yield

Common coupled fixed point theorem for two pairs compatible and sub-sequentially continuous mapping

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Journal of Ocean Engineering and science 2024年第4期9卷 401-407页

作者： h.m.Abu-Donia mona s.Bakry h.A.Atia Omnia m.A.Khater Raghda A.m.Attia Department of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt Department of mathematics Faculty of ScienceTanta UniversityTantaEgypt Department of Basic science Zagazig Higher Institute of Engineering and TechnologyZagazigEgypt Department of Basic science Higher Technological Institute 10th of Ramadan CityEl Sharqia 44634Egypt

This study establishes a common coupled fixed point for two pairs of compatible and sequentially continuous mappings in the intuitionistic fuzzy metric space that satisfy theφ-contractive *** basic definitions and theorems have been used from some recent scientific papers about the binary operator,t-norm,t-conorm,intuitionistic fuzzy metric space,and compatible mapping for reaching to the paper’s purpose.

关键词： Intuitionistic fuzzy metric space φ-contractive mapping Compatible mappings Couple fixed point

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)

magnesium oxide(mgO)nanoadsorbents in wastewater treatment:A comprehensive review

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Journal of magnesium and Alloys 2024年第5期12卷 1709-1773页

作者： h.C.s.Perera V.Gurunanthanan Anoop singh m.m.m.G.P.G.mantilaka G.Das sandeep Arya Department of Physics Khalifa UniversityAbu Dhabi12788United Arab Emirates Postgraduate Institute of science University of PeradeniyaPeradeniyaSri Lanka Department of humanities and sciences Guru Nanak Institutions Technical CampusIbrahimpatnamHyderabad501506India Centre for Global health Research Saveetha Medical College and HospitalsSaveetha Institute of Medical and Technical SciencesChennai602105Tamil NaduIndia Department of Physics University of JammuJammu and Kashmir180006India

Wastewater contamination by heavy metals and synthetic dyes presents a significant environmental challenge,necessitating effective and sustainable separation *** review article provides a detailed examination of magnesium oxide(mgO)nanoparticles as an innovative nanoadsorbent for wastewater treatment,with a specific focus on heavy metal and dye *** review comprehensively explores various aspects of mgO nanoparticles,including their structural characteristics and synthesis *** article delves into the morphology and crystallographic arrangement of mgO nanoparticles,offering insights into their structural *** the complexity of adsorption processes,the review identifies and analyzes parameters influencing the adsorption efficiency of mgO nanoparticles,such as temperature,ph,contact time,initial concentration,and co-existing *** interplay between these parameters and the adsorption capability of mgO nanoparticles emphasizes the importance of optimizing operational ***,the review assesses various synthesis methods for mgO nanoparticles,including sol-gel,hydrothermal,precipitation,green synthesis,solvothermal,and template-assisted *** discusses the advantages,limitations,and resulting nanoparticle characteristics of each method,enabling readers to grasp the implications of synthesis processes on adsorption *** comprehensive review consolidates current insights into the effectiveness of mgO nanoparticles as a potent nanoadsorbent for removing heavy metals and dyes from wastewater covering a wide spectrum of aspects related to mgO ***,there is a need to investigate the use of mgO in the treatment of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatment applications in real-time.

关键词： mgO nanoparticles Nanoadsorbent Wastewater treatment heavy metals Dye separation Adsorption synthesis methods