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Utilizing N-hydroxy-9-octadecenamide as a collector in flotation separation of bastnaesite and fluorite

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Journal of Rare Earths 2024年第8期42卷 1620-1628,I0008页

作者： Zhihao Guo Sultan ahmed Khoso Mengjie Tian Wei Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha410083China State Key Laboratory of Mineral Processing Bejing102600China hubei Key Laboratory for Eficient Utilization and Agglomeration of Metallurgic Mineral Resources Wuhan430081China Key Laboratoryof hunan Province for Cleanand Eficient Utilization of Strategic Calcium-containing Mineral Resources Central South University.Changsha410083China Department of Mining Engineering Mehran University of Engineering&TechnologyJamshoro76062Pakistan

Bastnaesite((Ce,La,Pr,Nd)CO_(3)F) is a significant light rare earth mineral found in nature,known for its fine-grained *** is commonly employed for the recovery of fine-grained bastnaesite *** serve as an essential flotation reagent that enhance the surface hydrophobicity of target minerals.A novel collector,N-hydroxy-9-octadecenamide(N-Oh-9-ODA),was synthesised in this study.N-Oh-9-ODA exhibits superior selectivity compared to the traditional collector oleic acid in the flotation separation of bastnaesite and *** experimental and co mputational results indicate that N-Oh-9-ODA exhibits superior selectivity due to its higher adsorption affinity for bastnaesite surface compared to fluorite *** zeta potential and the binding energies of the Ce 3d peaks in the X-ray photoelectron spectrum(XPS) of bastnaesite surface exhibit significant ***,fluorite surface demonstrates minimal alterations in its zeta potential and the binding energies of the Ca 2p peaks in its XPS after its interaction with N-Oh-9-ODA.

关键词： Bastnaesite Collector hydroxamic acids N-hydroxy-9-octadecenamide Oleic acid Rare earths

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Boosted photocatalytic removal of NO using direct Z-scheme UiO-66-Nh2/Bi2MoO6 nanoflowers heterojunction:mechanism insight and humidity effect

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Rare Metals 2024年第8期43卷 3758-3770页

作者： Jiang-Yu-Shan Liang hai-Tao Ren Abdelkader Labidi Qiu-hui Zhu Qi-Bing Dong ahmed A.allam ahmed Rady Chuan-Yi Wang School of Environmental Science and Engineering Shaanxi University of Science and Technology Zoology Department Faculty of ScienceBeni-Suef University Department of Zoology College of ScienceKing Saud University

in practical applications,relative humidity in the air is a key factor affecting the photocatalytic removal of NO,which is often overlooked in previous ***,we developed a direct Z-scheme UiO-66-Nh2/Bi2MoO6heterojunction with a nanoflower-like structure to systematically investigate the effect of relative humidity on photocatalytic removal of *** optimized heterojunction for the removal efficiency of NO was 71.6% at1.07 mg·m-3NO concentration（relative humidity=10%）,and the generation of NO2was only 1.1%.interestingly,with the increase in relative humidity,it showed a higher inhibition effect on NO2,while the removal of NO decreased slightly（8%）,which might be attributed to the affinity effect of NO2with water molecules and the competitive adsorption of h2O and NO on the surface of the heterojunction ***,the reaction pathways of NO removal at the developed heterojunctions were revealed by in situ DRiFTS *** work provides a novel vision for the development of direct Z-scheme heterojunction photocatalysts to effectively remove NO and inhibit the formation of toxic intermediate NO2under different humidities.

关键词： NO removal Relative humidity Direct Z-scheme Bismuth molybdate Visible-light photocatalysis

Novel design of a compact tunable dual band wireless power transfer(TDB-WPT)system for multiple WPT applications

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Frontiers of information Technology & Electronic Engineering 2024年第4期25卷 616-628页

作者： hany A.ATalLAh Rasha hussein ahmed Adel B.ABDEL-RAhMAN Department of Communications and Electronics Faculty of EngineeringSouth Valley UniversityQena 83523Egypt Egypt-Japan University of Science and Technology Alexandria 21934Egypt

in this study we present the design and realization of a tunable dual band wireless power transfer(TDB-WPT)coupled resonator *** frequency response of the tunable band can be controlled using a surface-mounted *** transmitter(Tx)and the receiver(Rx)circuits are *** top layer contains a feed line with an impedance of 50Ω.Two identical half rings defected ground structures(hR-DGSs)are loaded on the bottom using a varactor *** propose a solution for restricted WPT systems working at a single band application according to the operating *** effects of geometry,orientation,relative distance,and misalignments on the coupling coefficients were *** validate the simulation results,the proposed TDB-WPT system was fabricated and *** system occupied a space of 40 mm×40 *** can deliver power to the receiver with an average coupling efficiency of 98%at the tuned band from 817 to 1018 Mhz and an efficiency of 95%at a fixed band of 1.6 Ghz at a significant transmission distance of 22 *** results of the measurements accorded well with those of an equivalent model and the simulation.

关键词： Defected ground structure(DGS) Surface-mounted Tunable dual band wireless power transfer(TDB-WPT) Varactor

Enhancing indoor User Localization:An Adaptive Bayesian Approach for Multi-Floor Environments

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Computers, Materials & Continua 2024年第8期80卷 1889-1905页

作者： Abdulraqeb alhammadi Zaid ahmed Shamsan Arijit De Center for Artificial intelligence and Robotics(CAiRO) Malaysia-Japan International Institute of TechnologyUniversiti Teknologi MalaysiaKuala Lumpur54100Malaysia Department of Electrical Engineering College of EngineeringImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia Department of information Engineering Electronics and TelecommunicationsSapienza UniversityRome00185Italy

indoor localization systems are crucial in addressing the limitations of traditional global positioning system(GPS)in indoor environments due to signal attenuation *** complex indoor spaces become more sophisticated,indoor localization systems become essential for improving user experience,safety,and operational *** localization methods based on Wi-Fi fingerprints require a high-density location fingerprint database,but this can increase the computational burden in the online *** networks,which integrate prior knowledge or domain expertise,are an effective solution for accurately determining indoor user *** networks use probabilistic reasoning to model relationships among various localization parameters for indoor environments that are challenging to *** article proposes an adaptive Bayesian model for multi-floor environments based on fingerprinting techniques to minimize errors in estimating user *** proposed system is an off-the-shelf solution that uses existing Wi-Fi infrastructures to estimate user’s *** operates in both online and offline *** the offline phase,a mobile device with Wi-Fi capability collects radio signals,while in the online phase,generating samples using Gibbs sampling based on the proposed Bayesian model and radio map to predict user’s *** results unequivocally showcase the superior performance of the proposed model when compared to other existing models and *** proposed model achieved an impressive lower average localization error,surpassing the accuracy of competing ***,this noteworthy achievement was attained with minimal reliance on reference points,underscoring the efficiency and efficacy of the proposed model in accurately estimating user locations in indoor environments.

关键词： Localization positioning Bayesian fingerprinting received signal strength(RSS)

Proprotein convertase subtilisin/kexin type 9 inhibitors in peripheral artery disease:A review of efficacy,safety,and outcomes

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World Journal of Cardiology 2024年第7期16卷 397-401页

作者： Moiud Mohyeldin ahmed S Abuelgasim ahmed MG Mustafa Department of internal Medicine University of Medical Sciences and TechnologyKhartoum 11111Sudan

Peripheral artery disease(PAD)is a common condition characterized by atherosclerosis in the peripheral arteries,associated with concomitant coronary and cerebrovascular *** convertase subtilisin/kexin type 9(PCSK9)inhibitors are a class of drugs that have shown potential in hypercholesterolemic *** review focuses on the efficacy,safety,and clinical outcomes of PCSK9 inhibitors in PAD based on the literature indexed by *** such as FOURiER and ODYSSEY demonstrate the efficacy of evolocumab and alirocumab in reducing cardiovascular events,offering a potential treatment option for PAD *** evaluations from trials show few adverse events,most of which are injection-site reactions,indicating the overall safety profile of PCSK9 *** outcomes show a reduction in cardiovascular events,ischemic strokes,and major adverse limb ***,despite these positive findings,PCSK9 inhibitors are still underutilized in clinical practice,possibly due to a lack of awareness among care providers and cost *** research is needed to establish the long-term effects and cost-effectiveness of PCSK9 inhibitors in PAD patients.

关键词： Peripheral artery disease Proprotein convertase subtilisin/kexin type 9 inhibitors Cardiovascular risk reduction Evolocumab alirocumab Lipid-lowering therapy Major adverse limb events Clinical outcomes Cost-effectiveness Safety profile

Mafic and felsic magmatism in the Wadi Kalalat area, South Eastern Desert, Egypt: mineralogy, geochemistry and geodynamic evolution during the Neoproterozoic in the Nubian Shield

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Acta Geochimica 2024年第1期43卷 150-173页

作者： Adel A.Surour ahmed A.Madani Mohamed A.El-Sobky Faculty of Science Galala UniversityNew Galala CitySuez 43511Egypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt Egyptian Mineral Resources Authority P.O.Box 11517AbbasiyaCairoEgypt

in the south Eastern Desert of Egypt,two contrasting types of magmatism(mafic and felsic) are recorded in the Wadi Kalalat area,and form the Gabal El Motaghiarat and Gabal Batuga intrusions,*** two intrusions post-dates ophiolitic and arc associations represented by serpentinite and metagabbro-diorite,*** mafic intrusion has a basal ultramafic member represented by fresh peridotite,which is followed upward by olivine gabbro and anorthositic or *** mafic intrusion pertains to the alaskan-type mafic-ultramafic intrusions in the Arabian-Nubian Shield(ANS)being of tholeiitic nature and emplaced in a typical arc *** the other hand,the Gabal Batuga intrusion comprises three varieties of fresh A-type granites of high K-calc alkaline nature,which is peraluminous and garnetbearing in parts.A narrow thermal aureole in the olivine gabbro of the mafic intrusion was developed due to the intrusion of the Batuga *** results in the development of a hornfelsic melagabbro variety in which the composition changed from tholeiitic to a calc-alkaline composition due to the addition of S_(i)O_(2),al_(2)O_(3),alkalis,lithosphile elements(LiLEs) such as Rb(70 ppm) and Y(28 ppm) from the felsic *** the thermal aureole,Rb amounts 2-8 ppm and Y lies in the range is believed that the Gabal Batuga felsic intrusion started to emplace during the waning stage of an arc system,with transition from the pre-collisional(i.e.,arc setting) to post-collisional and within plate *** from which the Gabal Batuga granites were fractionated is high-K calc-alkaline giving rise to a typical post-collisional A-type granite(A_(2)-subtype) indicating an origin from an underplating crustal ***,it is stressed here that the younger granites in the ANS are not exclusively post-collisional and within-plate but most likely they started to develop before closure of the arc *** possible source(s) of mafic magmas

关键词： Wadi Kalalat Gabal El Motaghairat mafic intrusion Gabal Batuga felsic intrusion Arc setting Post-collision Within-plate

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Exploring Trees Diversity and Ecological Value of Mountain Forests in the Blue Nile Region of Sudan

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Open Journal of Ecology 2024年第3期14卷 245-256页

作者： Dafa-alla M. Dafa-alla haytham h. Gibreel ahmed A. h. Siddig Yousif E. Yagoub hashim A. Abdelkarim Khatir h.T. Saeed ahmed i. Abuelbashar Faculty of Forestry-Shambat University of Khartoum Khartoum Sudan harvard Forest Harvard University Petersham MA USA Faculty of Forest Science and Wood Technology University of Gezira Wad-Medani Sudan Department of Forestry and Range Sciences Faculty of Natural Resources and Environmental Studies Alsalam University Alfula Sudan Forest Research and Gum Arabic Centre Agricultural Research Corporation Khartoum-Soba Sudan

We carried out this research at Abu-Gaddaf Natural Forest Reserve (ANFR) which is located east of Blue Nile River, in Blue Nile State, Sudan. it aims at exploring tree composition assessing their diversity indices, and ecological importance values. For survey of types and estimation of density of tree species in the forest, we randomly distributed 97 circular sample plots (0.1 hectare (ha)). in each sample plot we identified all trees to the species level, recorded their frequencies and computed species diversity and importance value indices (iVi). A total of 13 tree species, which belong to 12 genera and nine families, were identified in the tree layer of the forest. Mean tree density in ANFR was 116 trees/ha, composed mainly of Boswellia papyrifera (Del.) hochst. (48), followed by Combretum hartmannianu (19) and Lannea fruticosa (18). Fabaceae was the most common family followed by Combretaceae and Malvaceae. B. papyrifera Delile hochst was the most abundant while Acacia seyal was the least abundant species. Species richness (R = 1.71), evenness (E = 0.69), dominance (0.24) indices and Simpson’s index of Diversity (D' = 0.76) suggest a moderate diversity, moderate numbers of individuals in each species and a moderate community stability. The research provides empirical results on diversity and ecological importance value of species, signifies the urging need to safeguard threatened species and to prioritize them for conservation, as well as the need to promote management of abundant species to provide multiple forest ecosystem services.

关键词： Tree Species Diversity Dry-Land Forest Sudan

Analysis of cerium substitution in Co-Sr based spinel ferrites for high frequency application

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Journal of Rare Earths 2024年第9期42卷 1755-1763页

作者： Laura Khudaysh inas A.ahmed Syeda Rabia Ejaz Sajjad Ahmad Khan Yasir A.haleem Mohamed M.i.rahi. Mahmood ali hafiz Muhammad Tahir Farid Zeinhom M.El-Bahy Department of Physics Faculty of ScienceJazan University Department of Chemistry Faculty of ScienceKing Khalid University Department of Physics The Government Sadiq College Women University institute of Physics Khwaja Fareed University of Engineering and Information Technology Department of Chemistry College of ScienceTaif University Centre of Excellence in Solid State Physics University of the Punjab Department of Physics Government College Department of Chemistry Faculty of ScienceAl-Azhar University

Spinel ferrites exhibit exceptional magnetic properties,making them a distinctive class of magnetic *** sol-gel technique was utilized for the synthesis of spinel ferrites with the chemical formula Co0.6Sr0.4CexFe2-xO4. Following that,a comprehensive X-ray diffraction analysis unveiled the crystalline cubic structure of the synthesized *** the utilization of the M-h loop approach,the ferromagnetic attributes of ferrites were assessed,and the assimilation of rare earth elements led to substantial enhancements in saturation magnetization,remanence,and *** ferrites with a high concentration of rare earth elements have improved direct current resistivity and activation *** logarithm of a material's resistance increased from 5.29 to 8.12 Ω·cm as cerium is *** a change in the amount of cerium,the activation energy goes up from 0.19 to *** changing the frequency from 5.5 to 9.5 Ghz,the dielectric characteristics were *** the frequency goes up,the dielectric constant goes *** ferrites that have been made better in every way can be used in high-frequency applications.

关键词： Activation energy DC electrical resistance Remanence magnetization Cobalt strontium spinel ferrites high frequency application Rare earths

Challenges to establishing and maintaining kidney transplantation programs in developing countries:What are the coping strategies?

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World Journal of Methodology 2024年第2期14卷 1-16页

作者： Rabea ahmed Gadelkareem Amr Mostafa Abdelgawad Nasreldin Mohammed Mohammed ali Zarzour Mahmoud Khalil ahmed Reda hisham Mokhtar hammouda Department of Urology Assiut Urology and Nephrology HospitalFaculty of MedicineAssiut UniversityAssiut 71515Egypt

Kidney transplantation(KT)is the optimal form of renal replacement therapy for patients with end-stage renal ***,this health service is not available to all patients,especially in developing *** deceased donor KT programs are mostly absent,and the living donor KT centers are ***-center studies presenting experiences from developing countries usually report a variety of *** review addresses these challenges and the opposing strategies by reviewing the single-center experiences of developing *** financial challenges hamper the infrastructural and material availability,coverage of transplant costs,and qualification of medical *** sociocultural challenges influence organ donation,equity of beneficence,and regular follow-up *** interests and motives for transplantation may result from high medicolegal responsibilities in KT practice,intense potential psychosocial burdens,complex qualification protocols,and low productivity or compensation for KT *** medical literacy about KT advantages is prevalent among clinicians,patients,and the *** inefficient organizational and regulatory oversight is translated into inefficient healthcare systems,absent national KT programs and registries,uncoordinated job descriptions and qualification protocols,uncoordinated on-site investigations with regulatory constraints,and the prevalence of commercial KT *** challenges resulted in noticeable differences between KT services in developed and developing *** coping strategies can be summarized in two main mechanisms:The first mechanism is maximizing the available resources by increasing the rates of living kidney donation,promoting the expertise of medical personnel,reducing material consumption,and supporting the establishment and maintenance of KT *** latter warrants the expansion of the public sector and the elimination of non-ethical KT *** second mechanism is recru

关键词： Challenges Coping strategies Developing countries Kidney transplantation Low resources Single-center