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Oxidative dissolution of Cr(OH)_(3) and mixed Fe-Cr(Ⅲ)phases by aqueous mn(Ⅲ)-pyrophosphate complex

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Journal of Environmental Sciences 2024年第5期139卷 105-113页

作者： mismel Ruiz-Garcia jordan Stanberry Giovanna Ballerini Ribeiro Vasileios Anagnostopoulos Department of Chemistry University of Central FloridaOrlando FL 32816USA

The key role of manganese(mn)in the biogeochemical cycle of trace elements has been of great interest in recent ***,the redox properties of aqueous mn(Ⅲ)have been studied to a lesser ***(Ⅲ)is not stable in solution by ***,when complexed with inorganic ligands,it has shown potential to oxidize and reduce trace *** the present study,we are exploring the redox characteristics of the complex mn(Ⅲ)-Pyrophosphate(mn(Ⅲ)-PP).This complex is stable over a wide range of pH values but requires the ratio of mn:PP to be less than 1:***,the redox reaction of chromium(Cr(Ⅲ))and mn(Ⅲ)-PP is investigated.A solid,Cr(OH)_(3),is used as a source of Cr(Ⅲ).For this reaction,environmentally relevant parameters,such as pH,ionic strength,ratio mn(Ⅲ)/Cr(Ⅲ),and excess of ligand,were *** showed that mn(Ⅲ)can effectively oxidize Cr(Ⅲ)to Cr(Ⅵ),taking about 15 days for the reaction to *** reaction occurs only under acidic conditions(pH4),and with a low excess of *** initial mn(Ⅲ)concentration decreases as the Cr(Ⅵ)is produced,and Cr(Ⅵ)can be adsorbed back into the Cr(OH)_(3)surface,limiting the mobility of this toxic *** this adsorption,significant amounts of Cr(VI)are release in the aqueous *** study shows the importance of a mobile species(mn-PP complex)in the oxidation of Cr(Ⅲ)and the release of Cr(Ⅵ)to the environment.

关键词： Chromium manganese Pyrophosphate complex Sorption Ionic strength Redox

Aging impairs the osteocytic regulation of collagen integrity and bone quality

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Bone Research 2024年第1期12卷 78-94页

作者： Charles A.Schurman Serra Kaya Neha Dole Nadja m.maldonado Luna Natalia Castillo Ryan Potter Jacob P.Rose Joanna Bons Christina D.King jordan B.Burton Birgit Schilling Simon melov Simon Tang Eric Schaible Tamara Alliston Department of Orthopaedic Surgery University of CaliforniaSan FranciscoCA 94143USA UC Berkeley/UCSF Graduate Program in Bioengineering San FranciscoCA 94143USA Buck Institute for Research on Aging NovatoCA 94945USA Washington University in St Louis Department of OrthopedicsSt.LouisMO 63130USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Poor bone quality is a major factor in skeletal fragility in elderly *** molecular mechanisms that establish and maintain bone quality,independent of bone mass,are unknown but are thought to be primarily determined by *** hypothesize that the age-related decline in bone quality results from the suppression of osteocyte perilacunar/canalicular remodeling(PLR),which maintains bone material *** examined bones from young and aged mice with osteocyte-intrinsic repression of TGFβsignaling(TβRII^(ocy−/−))that suppresses *** control aged bone displayed decreased TGFβsignaling and PLR,but aging did not worsen the existing PLR suppression in male TβRII^(ocy−/−)*** relationship impacted the behavior of collagen material at the nanoscale and tissue scale in macromechanical *** effects of age on bone mass,density,and mineral material behavior were independent of osteocytic TGFβ.We determined that the decline in bone quality with age arises from the loss of osteocyte function and the loss of TGFβ-dependent maintenance of collagen integrity.

关键词： maintain primarily integrity

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

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)

On multi-Granulation Rough Sets with Its Applications

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Computers, materials & Continua 2024年第4期79卷 1025-1038页

作者： Radwan Abu-Gdairi R.mareay m.Badr Department of mathematics Faculty of ScienceZarqa UniversityZarqa13132Jordan Department of mathematics Faculty of ScienceKafrelsheikh UniversityKafrelsheikh33516Egypt Department of mathematics Faculty of ScienceNew Valley UniversityEl Kharga72713Egypt

Recently,much interest has been given tomulti-granulation rough sets (mGRS), and various types ofmGRSmodelshave been developed from different viewpoints. In this paper, we introduce two techniques for the classificationof mGRS. Firstly, we generate multi-topologies from multi-relations defined in the universe. Hence, a novelapproximation space is established by leveraging the underlying topological structure. The characteristics of thenewly proposed approximation space are *** introduce an algorithmfor the reduction ***, a new approach for the classification ofmGRS based on neighborhood concepts is introduced. Finally, areal-life application from medical records is introduced via our approach to the classification of mGRS.

关键词： multi-granulation rough sets data classifications information systems interior operators closure operators approximation structures

A Reputation-Based AODV Protocol for Blackhole and malfunction Nodes Detection and Avoidance

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Computers, materials & Continua 2024年第8期80卷 1867-1888页

作者： Qussai m.Yaseen monther Aldwairi Ahmad manasrah Artificial Intelligence Research Center(AIRC) College of Engineering and Information TechnologyAjman UniversityAjman346United Arab Emirates Department of Computer Information Systems Faculty of Computer and Information TechnologyJordan University of Science and TechnologyIrbid22110Jordan College of Technological Innovation Zayed UniversityAbu Dhabi144534United Arab Emirates Faculty of Information Technology and Computer Science Yarmouk UniversityIrbid21163Jordan Computer Information Systems Higher Colleges of TechnologySharjah341214United Arab Emirates

Enhancing the security of Wireless Sensor Networks(WSNs)improves the usability of their ***,finding solutions to various attacks,such as the blackhole attack,is crucial for the success of WSN *** paper proposes an enhanced version of the AODV(Ad Hoc On-Demand Distance Vector)protocol capable of detecting blackholes and malfunctioning benign nodes in WSNs,thereby avoiding them when delivering *** proposed version employs a network-based reputation system to select the best and most secure path to a *** achieve this goal,the proposed version utilizes the Watchdogs/Pathrater mechanisms in AODV to gather and broadcast reputations to all network nodes to build the network-based reputation *** minimize the network overhead of the proposed approach,the paper uses reputation aggregator nodes only for forwarding reputation ***,to reduce the overhead of updating reputation tables,the paper proposes three mechanisms,which are the prompt broadcast,the regular broadcast,and the light broadcast *** proposed enhanced version has been designed to perform effectively in dynamic environments such as mobile WSNs where nodes,including blackholes,move continuously,which is considered a challenge for other *** the proposed enhanced protocol,a node evaluates the security of different routes to a destination and can select the most secure routing *** paper provides an algorithm that explains the proposed protocol in detail and demonstrates a case study that shows the operations of calculating and updating reputation values when nodes move across different ***,the paper discusses the proposed approach’s overhead analysis to prove the proposed enhancement’s correctness and applicability.

关键词： AODV blackhole malfunction nodes pathrater reputation system wireless sensor networks(WSNs) watchdogs

Rare earth based mgPm_(2)X_(4)(X=S,Se) spinel chalcogenides for spintronic and thermoelectric applications

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Journal of Rare Earths 2024年第8期42卷 1577-1585,I0006页

作者： Tariq m.Al-Daraghmeh Omar Zayed Ghulam m.mustafa Taharh Zelai Bisma Younas Hind Albalawi S.Bouzgarrou Othman Hakami Q.mahmood Khaild I.Hussein Basic Sciences Department King Abdullah II School of EngineeringPrincess Sumaya University For TechnologyPO.Box 1438Al-jubaiha11941AmmanJordan Department of Physics Division of Science&TechnologyUniversity of EducationLahorePakistan Department of Physics Faculty of ScienceJazan University JazanSaudi Arabia Department of Physics The University of LahoreLahorePakistan Department of Physics College of SciencesPrincess Nourah bint Abdulrahman University(PNU)PO.Box 84428Riyadh11671Saudi Arabia Department of Physics College of ScienceQassim UniversityPo.64BuraidahSaudi Arabia Laboratoire de microelectronique et Instrumentation(UR 03/13-04)Faculte des Sciences de monastir Avenue de I'Environnement 5000MonastirTunisia Department of Chemistry Faculty of ScienceJazan University JazanSaudi Arabia Basic&Applied Scientifc Research Center Department of PhysicsCollege of ScienceImam Abdulrahman Bin Faisal UniversityPO.Box 1982Dammam 31441Saudi Arabia Department of Radiological Sciences College of Applied Medical SciencesKing Khalid UniversityAbha61421Saudi Arabia

In current report,the structural,magnetic,and thermoelectric properties of RE doped mgPm_(2)X_(4)(X=S,Se) spinels were *** energy difference in ferromagnetic and antiferromagnetic states reveals the stability of mgPm_(2)(S/Se)_(4) in the ferromagnetic *** co mputation of enthalpy of formation also ascertains thermodynamic stability of crystal ***-dependent band structure and density of states analysis reveal ferromagnetic semiconducting character showing different electronic behavior in both spin *** room temperature ferromagnetism,spin polarization and Curie temperature are estimated from exchange energies *** addition,exchange constants(N_(0)α and N_(0)β),exchange energy Δ_(x)(pd),crystal ifeld energy,and double exchange mechanism were studied to explore the magnetic ***,the electrical conductivity,thermal conductivity,Seebeck co-efficient,and power factor show effect on electrons spin and their potential for thermoelectric devices.

关键词： Rare earth elements Spintronic applications Thermoelectric effects Exchange energies

memory access optimization for particle operations in computational fluid dynamics-discrete element method simulations

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Particuology 2023年第7期78卷 97-110页

作者： Deepthi Vaidhynathan Hariswaran Sitaraman Ray Grout Thomas Hauser Christine m.Hrenya jordan musser Computational Science Center National Renewable Energy LaboratoryUnited States Research Computing University of ColoradoBoulderUnited States Chemical and Biological Engineering University of ColoradoBoulderUnited States Computational Science and Engineering National Energy Technology LaboratoryUnited States

Computational Fluid Dynamics-Discrete Element method is used to model gas-solid systems in several applications in energy,pharmaceutical and petrochemical *** performance bot-tlenecks often limit the problem sizes that can be simulated at industrial *** data structures used to store several millions of particles in such large-scale simulations have a large memory footprint that does not fit into the processor cache hierarchies on current high-performance-computing platforms,leading to reduced computational *** paper specifically addresses this aspect of memory access bottlenecks in industrial scale *** use of space-flling curves to improve memory access patterns is described and their impact on computational performance is quantified in both shared and distributed memory parallelization *** morton space flling curve applied to uniform grids and k-dimensional tree partitions are used to reorder the particle data-structure thus improving spatial and temporal locality in *** performance impact of these techniques when applied to two benchmark problems,namely the homogeneous-cooling-system and a fluidized-bed,are *** optimization techniques lead to approximately two-fold performance improvement in particle focused operations such as neighbor-list creation and data-exchange,with~1.5 times overall improvement in a fluidization simulation with 1.27 million particles.

关键词： CFD-DEm memory access optimization Spatial reordering Performance optimization

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