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International Journal of mining Science and Technology 2024年第4期34卷 557-571页

作者： Asmae el-bahi Yassine Taha Yassine Ait-Khouia Abdellatif elghali mostafa Benzaazoua Geology&Sustainable mining Institute(GSmI) Mohammed VI Polytechnic UniversityBen Guerir 43150Morocco

Recycling waste frying oils for the synthesis of flotation reagents presents a promising avenue for sustainable waste ***,it offers a cost-effective solution for crafting a specialized collector designed to efficiently remove carbonates and enhance phosphate enrichment in froth flotation *** study focuses on the synthesis of an anionic collector using the saponification reaction of a frying oil sample,subsequently applied to the flotation of calcite and *** elucidate the adsorption mechanisms of the frying oil collector(FrOC)and sodium oleate,a reference collector,on fluorapatite,calcite,dolomite,and quartz surfaces,comprehensive experiments were conducted,including zeta potential measurements and Fourier transform infrared *** revealed diverse adsorption affinities of the molecules towards these *** assess the practical performance of the collector,flotation tests were conducted using a natural phosphate ore mixture,employing a BoxBehnken experimental ***,under optimized conditions(pH 9,1000 g/t of FrOC,3.5 min of conditioning,and 6 min of flotation),FrOC exhibited excellent performance,with calcite and dolomite recoveries exceeding 80%,while apatite recovery in the concentrate fraction remained below 10%.This work exemplifies both circular economy practices and the distinctive approach to sustainable mineral processing.

关键词： Frying oils recycling Phosphate beneficiation Flotation separation Green surfactants Sustainability

Nonlinear boundary control problem of hyperbolic systems

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Journal of Control and Decision 2024年第1期11卷 73-83页

作者： A.Bouhamed A.el Kabouss H.Bouzahir ISTI Lab Ibn Zohr UniversityENSAAgadirMorocco Faculty of sciences Moulay Ismail UniversityMeknesMorocco

The paper is devoted to the study of optimal control of a hyperbolic system,where the control enters the system through the *** hyperbolic system is the wave equation on a smooth and open domain,where the boundary condition involves the normal derivative at the boundary of z,the time derivative of z times a constant k,and a nonlinear term ***,z is the state and u is the control,satisfying some boundedness condition depending on *** functional cost consists of the energy and the difference between the solution of the system at final time,and a desired state in *** a closed convex set,we prove the existence of an optimal control that minimises the cost functional using a priori ***,using the differentiability of the cost functional with respect to the control,we establish the characterisation by deriving necessary conditions that an optimal control must satisfy.A numerical approach is successfully illustrated by simulations.

关键词： Non-linear system hyperbolic system boundary control optimal control controllability

Evaluation of urea breath test as a diagnostic tool for Helicobacter pylori infection in adult dyspeptic patients

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World Journal of Gastroenterology 2024年第17期30卷 2302-2307页

作者： Zeinab Nabil Ahmed Said Asmaa mohamed el-Nasser Department of medical microbiology&Immunology Faculty of Medicine for Girls Al-Azhar UniversityNasr City 11754CairoEgypt

In this editorial,we discuss the article in the World Journal of *** article conducts a meta-analysis of the diagnostic accuracy of the urea breath test(UBT),a non-invasive method for detecting Helicobacter pylori(***)infection in *** is based on radionuclide-labeled *** methods,both invasive and non-invasive,are available for diagnosing *** infection,inclu-ding endoscopy with biopsy,serology for immunoglobulin titers,stool antigen analysis,and *** guidelines recommend UBTs as the primary choice for diagnosing *** infection and for reexamining after eradication *** is used to be the first choice non-invasive test due to their high accuracy,specificity,rapid results,and ***,its performance remains unaffected by the distribution of *** in the stomach,allowing a high flow of patients to be *** its widespread use,the performance characteristics of UBT have been inconsistently described and remain incompletely *** are two UBTs available with Food and Drug Administration approval:The 13C and 14C *** tests are affordable and can provide real-time *** may prefer the 13C test because it is non-radioactive,compared to 14C which uses a radioactive isotope,especially in young children and pregnant *** there was heterogeneity among the studies regarding the diagnostic accuracy of both UBTs,13C-UBT consistently outperforms the *** makes the 13C-UBT the preferred diagnostic ***,the provided findings of the meta-analysis emphasize the significance of precise considerations when choosing urea dosage,assessment timing,and measurement techniques for both the 13C-UBT and 14C-UBT,to enhance diagnostic precision.

关键词： Helicobacter pylori Urea breath test Diagnosis Diagnostic test accuracy meta-analysis

Proposition and design of a new micro-Architected Domes family:A biomimicry-based approach

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Frontiers of Architectural Research 2024年第3期13卷 650-667页

作者： Nadir Rihani Iatimad Akhrif mostapha el Jai Euromed Polytechnic School Euromed Center of ResearchEuromed University of FesFesMorocco mechanic Mechatronic and Command LaboratoryENSAM-MeknesMoulay Ismail UniversityMeknesMorocco

In the last decade,micro-architected structures have gained significant attention in academia and industry for their lightweight,strong,and thermally efficient *** by biomimicry design,this paper presents a novel ribbed family of additively manufactured micro-Architected Domes(mAD).The design incorporates tetrapod pyramid unit cells,golden ratio-based fractal patterns,Schoen’s minimal Gyroid,and spherical *** study focuses on dome radius,height,and azimuth/elevation partitioning as input variables,with the main output being ribbed micro-cell *** relationships between unit-cells’diameter and input variables were established through problem-solving and numerical computations:linear dependency with the dome radius and hyperbolic dependency with the azimuth and elevation *** proposed design successfully adhered to the Surface-to-Volume ratio of Schoen’s minimal Gyroid,achieving an average volume relative density of 2.5%,confirming its lightweight *** feasibility of the design was further supported by fabricating three specimens using Filament Fused *** research showcases the potential of biomimicry-inspired micro-architected structures,paving the way for innovative applications in various fields.

关键词： micro-architected structures Domes Biomimicry mathematical design Optimization Fractal decomposition

Landau quantization effects on damping Kawahara solitons in electron–positron–ion plasma in rotating ionized medium

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Communications in Theoretical Physics 2024年第10期76卷 143-152页

作者： E I el-Awady S Hussain N Akhtar Department of Physics Faculty of Science Port Said University Theoretical Physics Division (TPD) PINSTECH

For the dynamics of three-dimensional electron–positron–ion plasmas, a fluid quantum hydrodynamic model is proposed by considering Landau quantization effects in dense ***–neutral collisions in the presence of the Coriolis force are also considered. The application of the reductive perturbation technique produces a wave evolution equation represented by a damped Korteweg–de Vries equation. This equation, however, is insufficient for describing waves in our system at very low dispersion coefficients. As a result, we considered the highest-order perturbation, which resulted in the damped Kawahara equation. The effects of the magnetic field, Landau quantization, the ratio of positron density to electron density, the ratio of positron density to ion density, and the direction cosine on linear dispersion laws as well as soliton and conoidal solutions of the damped Kawahara equation are explored. The understanding from this research can contribute to the broader field of astrophysics and aid in the interpretation of observational data from white dwarfs.

关键词： Coriolis force Kawahara equation Landau quantization magnetoplasmas quantum plasma solitary and cnoidal waves

Enhanced heavy and extra heavy oil recovery:Current status and new trends

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Petroleum 2024年第3期10卷 399-410页

作者： Sayed Gomaa Khalaf G.Salem A.N.el-hoshoudy mining and Petroleum Engineering Department Faculty of EngineeringAl-Azhar UniversityEgypt Department of Reservoir Engineering South Valley Egyptian Petroleum Holding Company(GANOPE)CairoEgypt PVT Lab-Production Department Egyptian Petroleum Research Institute(EPRI)Cairo 11727Egypt PVT-Service Center Egyptian Petroleum Research Institute(EPRI)Cairo 11727Egypt

Due to the increased demand for energy resources these days,especially due to the Russian-Ukrainian war,the focus of the major countries is turning strongly towards improving oil production,especially heavy and extra heavy oil,which represents 40%of the world oil ***-based and thermal(EOR)procedures are promising techniques for recovering heavy oil reservoirs,but they suffer from a sequence of problems and complications that arise after long-term *** complications comprise steam breakthrough,steam overlap,and steam/rock *** research presents the currently applied techniques to maximize the productivity of heavy oil,such as steam injection,cyclic steam stimulation,in-situ combustion,and steam-assisted gravity *** technologies face numerous obstacles,as they are energy and water-intensive processes that are not environmentally *** research also presents future trends in energy-saving and environmentally friendly techniques that enhance heavy oil recovery through vapor extraction(VAPEX)steam-solvent hybrid techniques,electromagnetic energy,sonication,and *** findings of this review reported that all the presented techniques focus on how to reduce the oil viscosity and in-situ upgrade the crude oil *** turn,these enhance both the productivity rate and oil recovery and minimize the production *** article can be considered a comprehensive review of thermal recovery methods in heavy and extra-heavy oil,in addition to screening criteria used for each method.

关键词： Enhanced oil recovery Heavy crude oil Steam flood Hybrid techniques Nanotechnology

Adherence to Advisory Committee on Immunization Practices in diabetes mellitus patients in Saudi Arabia:A multicenter retrospective study

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World Journal of Diabetes 2024年第3期15卷 440-454页

作者： Saleh Fahad Alqifari Aya K Esmail Dalal m Alarifi Ghalya Y Alsuliman maram m Alhati may R mutlaq mohammed Aldhaeefi Shaden A Alshuaibi Palanisamy Amirthalingam Abrar Abdallah Afaf S Wasel heba R Hamad Shoroq Alamin Tasneem H Atia Tariq Alqahtani Department of Pharmacy Practice University of TabukTabuk 71491Saudi Arabia Department of Clinical Sciences Sulaiman Alrajhi UniversityQassim 52726Saudi Arabia Department of Family medicine International Medical CenterJeddah 23214Saudi Arabia Clinical and Administrative Pharmacy Sciences College of PharmacyHoward UniversityWashingtonDC 20059United States Department of Pharmacology King Saud Bin Abdulaziz University for Health SciencesKing Abdullah International Medical Research CenterRiyadh 11481Saudi Arabia

BACKGROUND Patients with diabetes mellitus(Dm)are predisposed to an increased risk of infection signifying the importance of vaccination to protect against its potentially severe *** Centers for Disease Control and Prevention/Advisory Committee on Immunization Practices(CDC/ACIP)issued immunization recommendations to protect this patient *** To assess the adherence of patients with Dm to the CDC/ACIP immunization recommendations in Saudi Arabia and to identify the factors associated with the vaccine adherence *** An observational retrospective study conducted in 2023 was used to collect data on the vaccination records from 13 diabetes care centers in Saudi Arabia with 1000 eligible patients in phase I with data collected through chart review and 709 patients in phase II through online *** Among participants,10.01%(n=71)had never received any vaccine,while 85.89%(n=609)received at least one dose of the coronavirus disease 2019(COVID-19)vaccine,and 34.83%(n=247)had received the annual influenza *** 2.96%(n=21),2.11%(n=15),and 1.12%(n=8)received herpes zoster,tetanus,diphtheria,and pertussis(Tdap),and human papillomavirus(HPV)vaccines,*** patients with Dm in Saudi Arabia,the rate of vaccination for annual influenza and COVID-19 vaccines was higher compared to other vaccinations such as herpes zoster,Tdap,pneumococcal,and *** such as vaccine recommendations provided by family physicians or specialists,site of care,income level,Dm-related hospitalization history,residency site,hemoglobin A1c(HbA1c)level,and health sector type can significantly influence the vaccination rate in patients with *** non-vaccinated patients with Dm,the most reported barriers were lack of knowledge and fear of side *** signifies the need for large-scale research in this area to identify additional factors that might facilitate adherence to CDC/ACIP vaccine recommendations in patients with *** In S

关键词： Diabetes mellitus Vaccine recommendation COVID-19 vaccine Influenza vaccine Pneumococcal vaccine Immunization Retrospective study

Wood By-Products as UV Protection:A Consequence Review

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Journal of Renewable materials 2024年第4期12卷 699-720页

作者： Naglaa Salem el‑Sayed mohamed Hasanin Samir Kamel Cellulose and Paper Department National Research CentreCairo12622Egypt

In recent decades,the ozone layer has suffered considerable damage,increasing the entry of ultraviolet(UV)light into the atmosphere and reaching the earth’s surface,negatively affecting ***,researchers aimed to solve this problem by synthesizing advanced UV-shielding *** the other hand,developing an easy and green strategy to prepare functional materials with outstanding properties based on naturally abundant and environmentally friendly raw materials is highly desirable for sustainable *** biomass-derived materials are sustainable and biodegradable,they present a promising substitute for petroleum-based *** three main structural constituents of the plant biomass-based materials that are naturally available are cellulose,hemicellulose,and *** review details current developments using wood-based products such as cellulose,hemicellulose,and lignin in UV-shielding *** will start with assembling the structure and chemistry of cellulose,hemicellulose,and lignin,followed by their contributions to preparing UV-shielding ***,it will briefly discuss the different processing methods for the design of UV-shielding *** wood by-products offer additional opportunities to use the whole tree harvest.

关键词： UV-shielding wood cellulose lignin hemicellulose sunlight protection

Intravesical instillation of platelet-rich plasma for treatment of interstitial cystitis/bladder pain syndrome:A pilot study

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Current Urology 2024年第1期18卷 49-54页

作者： Ahmed S.el Hefnawy mohamed Attya Ahmed Hasan Esam el Sawy mohamed Abdel-Razik Nasr el-Tabey mansoura Urology and Nephrology Center Faculty of MedicineMansoura UniversityMansouraEgypt

Objective:The aim of this study was to evaluate the feasibility of intravesical instillation of platelet-rich plasma(PRP)to treat interstitial cystitis/bladder pain syndrome(IC/BPS).materials and methods:Twenty PRP samples were tested in vitro for stability after exposure to urine samples with different pH.A pilot study involving 21 female patients with IC/BPS was conducted,and 6 weekly doses of autologous PRP(50 mL)were *** were followed up at the 2nd,4th,8th,and 12th weeks after terminating *** primary endpoint was the visual analog scale(VAS)for pain,and the secondary endpoints included the IC symptom index,IC problem index of the O'Leary-Sant questionnaire and global response assessment,urine culture,and *** was defined as a reduction in VAS by 30%or more compared with basal level,and adverse events were ***:The mean±SD of VAS was significantly reduced compared with basal level(4.4±2.6 vs.8.8±1.1,respectively,p=0.001).meanwhile,80%of cases were considered successful,with a 50.1%reduction in the mean score compared with the basal *** mean±SD of IC symptom index and IC problem index significantly improved compared with the basal *** response assessment was markedly,moderately,and slightly improved in 2(10%),10(50%),and 5(25%)patients,respectively,and showed no change in 3(15%).Three patients had positive urine cultures at follow-up,but 1 withdrew after 2 sessions because of a lack of ***:Repeated intravesical instillation of PRP could be considered an effective and safe approach for treating IC/BPS.

关键词： Bladder pain syndrome Interstitial cystitis Platelet-rich plasma

Optimized system for combined production of electricity/green hydrogen for multiple energy pathways:a case study of Egypt

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Clean Energy 2024年第4期8卷 219-236页

作者： Reda Ragab mohamed HamdiHafez A.el Salmawy mohamed A.Ismail mechanical Power Engineering Department Zagazig UniversityZagazig 44519Egypt mechanical Engineering Department College of EngineeringKing Faisal UniversityAl-Ahsa 31982Saudi Arabia

By optimal sizing of a wind/photovoltaic hybrid renewable-energy(RE)system,trimming the surplus capacity to reduce the fluctuations in the electricity supplied to the grid,and using it to produce green hydrogen through electrolysis,a stable output with maximum possible capacity factor(CF)is generated to maintain the electricity grid ***,the trimmed energy is used in a secondary conversion path that minimizes the weighted average cost of the energy generated from the entire *** surplus power-to-gas conversion allows the use of green hydrogen to produce electricity,methanol,or ammonia subject to the resource availability,site characteristics,and financial *** on robust site selection criteria,the best performance is obtained at two sites:Ras Ghareb and minya,achieving the lowest energy cost with some variance in their *** the Ras Ghareb site,the optimally sized RE plant provided the grid with a quasi-steady capacity of 423 mW with a CF of 80.04%and was capable of injecting 2965.8648 GWh throughout the year with the lowest cost of 2.4355¢/kWh.A surplus of 3.9%of the total energy produced from the plant was directed to produce 1922-ton H_(2)/year,achieving the lowest cost of hydrogen production of$1.9745/kg H_(2).For the other selected site,minya,the clipped energy is used to produce 3330.47-ton H_(2)/year with an optimized lowest cost of$3.5268/kg H_(2).The difference in hydrogen costs was attributed to the number of full operating hours of the electrolyser in both *** cost is mainly affected by the electricity price and the electrolyser *** both tending to decrease,future forecasts show hydrogen cost reductions.

关键词： hybrid renewable-energy system(HRES) green hydrogen electrolysis power-to-gas methanol ammonia