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Application of Synthetic Iron Oxyhydroxide with Influencing Factors for Removal of As(Ⅴ) and As(Ⅲ) from Groundwater

Journal of Earth Science 2024年第3期35卷 998-1009页

作者： Shakeel ahmed Talpur Muhammad Yousuf Jat Baloch Chunli Su Javed Iqbal Aziz ahmed Hafeez ahmed Talpur School of Environmental Studies China University of GeosciencesWuhan 430078China diSPUTer Department of PsychologicalHealth and Territory SciencesUniversity“G.d′Annunzio”Chieti-Pescara66100 ChietiItaly College of New Energy and Environment Jilin UniversityChangchun 130021China School of Plant Environment and Soil SciencesLouisiana State University Agricultural CentreBaton Rouge LA 70803USA department od Engineering and Geology University“G.d′Annunzio”Chieti-Pescara66100 ChietiItaly

Synthesized iron oxyhydroxide was applied for the adsorptive removal of As(V)and As(III)from the aquas ***,this investigation highlighted the synergistic effect of calcium carbonate in conjunction with iron oxyhydroxide,resulting in enhanced removal *** experiment was conducted under various conditions:concentration,dosage,pH,agitation,and *** characterizations such as Brunauer Emmett Teller,X-ray diffraction,scanning electron microscopy,and Fourier transform infrared spectroscopy were implied to understand adsorption *** Langmuir model revealed optimal concentrations for As(V)=500μg/L at pH-5 and As(III)=200μg/L at pH-7,resulting in 95%and 93%adsorption efficiencies,*** adsorption capacities“qm”were found to be 1266.943μg/g for As(V)and 1080.241μg/g for As(III).Freundlich model demonstrated favorable adsorption by indicating“n>1”such as As(V)=2.542 and As(III)=2.707;similarly,the speciation factor“RLd As(III)=0.5,*** kinetic study presented a pseudo-second-order model as best fitted,indicating throughout chemisorption processes for removing As(V)and As(III).Furthermore,incorporating calcium carbonate presented a significant leap in the removal efficiency,indicating As(V)from 95%to 98%and As(III)from 93%to 96%,*** findings offer profound motivation for developing effective and sustainable solutions to tackle arsenic contamination,underscoring the exceptional promise of iron oxyhydroxide in conjunction with calcium carbonate to achieve maximum removal efficiency.

关键词： adsorption arsenic As(V) As(III) iron oxyhydroxide isotherms kinetics groundwater.

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Phytochemical analysis,antioxidant,acetylcholinesterase,andα-amylase inhibitors from Hippeastrum hybridum extract

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Journal of Traditional Chinese Medicine 2024年第3期44卷 496-504页

作者： Naila Sher Mushtaq ahmed Nadia Mushtaq department of Biotechnology University of Science and Technology Bannu-KPK 28100Pakistan department of Botany University of Science and Technology Bannu-KPK 28100Pakistan

OBJECTIVE:To investigate the effects of Hippeastrum hybridum(HH)as a free radical scavenger,and an inhibitor of the two enzymes i-e Alpha-amylase(α-amylase)and acetylcholinesterase(AChE).METHOdS:In this study,HH plant was preliminary analyzed for phytochemical screening and then tested for its antioxidant,anti-α-amylase,and anti-AChE efficiency via standard ***:Phytochemical analysis shows the existence of different compounds;while Coumarins and quinones were *** total phenolic,flavonoid,and tannins content were found to be(78.52±0.69)mg GAE/g,(2.01±0.04)mg RUE/g,and(58.12±0.23)mg TAE/g of plant extract respectively.28.02%±0.02%alkaloid and 2.02%±0.05%saponins were present in the HH *** HH extract showed the anti-oxidant property with IC50(50%inhibition)of(151.01±0.13)(HH),(79.01±0.04)(Ascorbic acid)for ferric reducing,(91.48±0.13)(HH),(48.02±0.11)(Ascorbic acid)against Ammonium molybdenum,(156.02±0.31)(HH),(52.38±0.21)(Ascorbic acid)against dPPH,136.01±0.21(HH),52.02±0.31(Ascorbic acid)against H_(2)O_(2),and 154.12±0.03(HH),(40.05±0.15)(Ascorbic acid)μg/mL against ABTS *** analysis indicated that HH caused a competitive type of inhibition ofα-amylase(V_(max)remained constant and Km increases from 10.65 to84.37%)while Glucophage caused the un-competitive type of inhibition i-e both Km and V_(max)decreased from40.49 to 69.15%and 38.86 to 69.61%*** K_(i),(inhibition constant);K_(I),(dissociation constant),K_(m),(Michaelis-Menten constant),and IC50 were found to be62,364,68.1,and 38.08±0.22 for HH and 12,101.05,195,34.01±0.21 for ***,HH causes an anon-competitive type of inhibition of AChE i-e Km remains constant while V_(max)decreases from 60.5%to74.1%.The calculated K_(i),K_(I),K_(m),and IC50 were found to be 32,36.2,0.05,and 18.117±***:From the current results,it is concluded that HH extract contains bioactive compounds,and could be a good alternative to controlling oxidant

关键词： Hippeastrum hybridum phytochemicals antioxidant alpha-amylase acetylcholinesterase

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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 Beijing102600China Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources Wuhan430081China Key Laboratoryof Hunan Province for Cleanand Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha410083China 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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Tilted global solar irradiance in Bahrain:an experimental study

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Clean Energy 2024年第2期8卷 27-34页

作者： N.Vasilikos C.Georgantopoulou H.Alajaimi S.H.Almajed M.ahmed d.Mathioulakis School of Mechanical Engineering Bahrain PolytechnicIsa TownPO Box 33349Kingdom of Bahrain School of Mechanical Engineering National Technical University of AthensHeroon Polytechniou 7 StZografos 15773AthensGreece

In the present work,tilted global solar irradiance data are presented and analysed,measured for a period of 1 year on the campus of Bahrain Polytechnic,Kingdom of Bahrain,from both a fixed photovoltaic panel and a moving one via a two-axis solar *** fixed panel faces south with an angle of 26°with respect to the horizontal,coinciding with the local geographical *** second panel is moved by two motors,controlled by a global positioning system and suitable software so that the Sun’s rays are perpendicular to the panel surface.A pyranometer is installed on each panel,recording the tilted global solar irradiance,stored by using a data *** analysis of the data obtained shows a 33%solar energy gain on an annual basis for the moving panel(2780 versus 2088 kWh/m^(2) on the fixed panel).More importantly,in June,when the energy demand in Bahrain is elevated due to the increased residential cooling loads,the solar energy received by the moving panel is 54.7%higher compared with that of the fixed *** a percentage basis,the increase in solar energy from the moving panel is profound in the early morning and late evening ***,the reduction in the solar energy received by the fixed panel from May to June does not appear in the moving panel because of the adjustable orientation of the *** the year,the mean daily solar power varies between 0.37 and 0.56 kW/m^(2) for the fixed panel,and 0.45 and 0.70 kW/m^(2) for the moving *** winter,solar energy fluctuations are elevated due to erratic weather conditions that present a peak standard deviation of 28%of the corresponding *** data presented are useful for potential solar investments in Gulf countries.

关键词： tilted solar irradiance renewable energy solar tracking photovoltaic Gulf Cooperation Council Countries

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Potential of guar gum as a leaky gut model in broilers: digestibility,performance, and microbiota responses

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Animal Nutrition 2024年第2期17卷 177-187页

作者： amine Mellouk Tahir Mahmood Maamer Jlali Nuria Vieco-Saiz Virginie Michel Pierre Cozannet Sarper Ozbek Yves Mercier Estelle devillard Jessika Consuegra department of R&I in Monogastric Animal Nutrition European Laboratory of Innovation Science & Expertise (ELISE)

diet is a major modulator of animal resilience and its three pillars: host?s immune response, gut microbiota, and intestinal barrier. In the present study, we endeavour to delineate a challenging condition aimed to degrade these pillars and elucidate its impact on broiler performance and nutrient digestibility. To attain this objective, we opted to use guar gum(GG) as a source of galactomannan. A series of three in vivo experiments were conducted employing conventional or semi-purified diets, supplemented with or without GG during the grower phase(14-28 d). Our findings demonstrate a substantial decline in animal performance metrics such as body weight(reduced by 29%, P d intake(decreased by 12%, P d feed conversion ratio(up to 58% increase, P d diet with incremental doses of GG resulted in a linear reduction(P digestibility of dry matter and apparent metabolisable energy. Additionally, a marked reduction in ileal endogenous losses, as well as apparent and standardised digestibility of all amino acids with varying proportions(P d. These alterations were accompanied by disrupted gut integrity assessed by fluorescein isothiocyanate-dextran(FITC-d)(P d by elevated levels of acute-phase proteins,namely orosomucoid and serum amyloid A in the sera(P = 0.03), and increased m RNA expression levels of IL-1, IL-6, IL-8, Inos, and K203 genes in the ileum, along with a decrease in Ig A levels in the gut lumen(P d activity were characterised by reduced diversity and richness(Shannon index, P = 0.005) in the presence of GG. Consequently, our results revealed diminished levels of shortchain fatty acids(P = 0.01) and their producer genera, such as Clostridium＿XIVa and Blautia, in the gut caeca, coupled with excessive accumulation of lactate(17-f

关键词： Animal resilience Guar gum Broilers' gut health Performance digestibility Microbiota

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Evaluating mechanism of banana pseudo-stem retting using seawater:A cost-effective surface pre-treatment approach

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Journal of Bioresources and Bioproducts 2024年第3期9卷 322-335页

作者： Prince Hotor ahmed H.Hassanin Osbert Akatwijuka Mohamed A.H.Gepreel Mitsuo Yamamoto Yukie Saito ahmed Abdel-Mawgood Egypt-Japan University of Science and Technology Biotechnology ProgramAlexandria GovernorateNew Borg Al Arab 21934Egypt Alexandria University Department of Textile EngineeringAlexandria GovernorateBab Sharqi 5424041Egypt Egypt-Japan University of Science and Technology Material Science and EngineeringAlexandria GovernorateNew Borg Al Arab 21934Egypt Graduate School of Agricultural and Life Sciences The University of TokyoBunkyo-KuTokyo 113-8657Japan

Retting has been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach for *** its global abundance,banana pseudo-stem is a promising agro-waste for lignocellulosic fiber *** this study,fibers were extracted from the pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from the fresh seawater sample and screening for ligninolytic ability were *** load as well as laccase and manganese peroxidase enzyme activity profile assay during the retting duration were *** transform infrared(FT-IR)and X-day diffraction(XRd)analyses were also examined for both pre-treated and untreated extracted *** results shows that six out of the eight bacterial isolates had the ability to degrade *** treatments(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)recorded the highest viable bacterial load of 9.24×102 and 4.46×102 CFU,respectively,on the 14th day of the retting ***,the highest laccase and manganese peroxidase enzymes activity was recorded for(Raw stem+Raw seawater)and(Autoclaved stem+Raw seawater)treatments in the second to the third *** FT-IR spectra of the pre-treated fibers revealed relative reductions in peaks attributed to polysaccharides and other amorphous substances for all retting *** XRd diffractogram revealed that the crystallinity index(CI)of pre-treated fibers increased in all seawater retting treatment ***,the CI for fibers pre-treated under enzymatic conditions were enhanced even after five *** analysis for selected bacterial isolates showed homology to sequences of Bacillus velezensis,Shewanella sp.L8–5,and Citrobacter amalonaticus and Bacillus subtilis j8 *** these findings,it was suggested that physical,biological,and chemical actions were collectively involved in the seawater retting process of banana ps

关键词： Seawater retting Banana pseudo-stem Natural fiber Enzyme activity Colony forming unit

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Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 115-136页

作者： Yusuf Suleiman dambatta Changhe Li Mohd Sayuti ahmed A d Sarhan Min Yang Benkai Li Anxue Chu Mingzheng Liu Yanbin Zhang Zafar Said Zongming Zhou School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Mechanical Engineering department Ahmadu Bello UniversityZaria 810106Nigeria Mechanical Engineering department University of Malaya50603 Kuala LumpurMalaysia department of Mechanical Engineering King Fahd University of Petroleum&Minerals31261 DhahranSaudi Arabia State Key Laboratory of Ultra-Precision Machining Technology Department of Industrial and Systems Engineer-ingThe Hong Kong Polytechnic UniversityHong KongChina College of Engineering University of Sharjah27272 SharjahUnited Arab Emirates Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266100China

Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining *** involve the spray of an infinitesimal amount of mist-like lubricants during machining *** MQL system is affirmed to exhibit an excellent machining performance,and it is highly *** nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL *** have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these *** work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)*** effect different grinding modes and lubrication systems during the grinding operation was also *** concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower *** quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface *** was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication ***,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%***,regression analysis was used to obtain an optimum parameter *** observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics.

关键词： Minimum quantity lubrication(MQL) Ultrasonic assisted grinding(UAG) Eco-friendly lubricants Nanofluid Grinding Ceramic

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Lithium-Metal-Free Sulfur Batteries with Biochar and Steam-Activated Biochar-Based Anodes from Spent Common Ivy

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Energy & Environmental Materials 2024年第6期7卷 118-128页

作者： Pejman Salimi Willem Vercruysse Susana Chauque Saeed Yari Eleonora Venezia amine Lataf Nahal Ghanemnia Muhammad Shajih Zafar Mohammadhosein Safari An Hardy Remo Proietti Zaccaria dries Vandamme Istituto Italiano di Tecnologia via Morego 30Genoa 16163Italy department of Chemistry and Industrial Chemistry University of Genovavia Dodecaneso 31Genoa I-16146Italy Analytical and Circular Chemistry(ACC) Hasselt UniversityMartelarenlaan 42Hasselt BE3500Belgium Institute for Materials Research(imo-imomec) Hasselt UniversityMartelarenlaan 42Hasselt BE3500Belgium Centre for Environmental Sciences(CMK) Hasselt UniversityMartelarenlaan 42Hasselt BE3500Belgium Energyville Thor Park 8310Genk BE3600Belgium IMEC Division IMOMECWetenschapspark 1Diepenbeek BE3590Belgium

Lithium-sulfur batteries are emerging as sustainable replacements for current lithium-ion *** commercial viability of this novel type of battery is still under debate due to the extensive use of highly reactive lithium-metal anodes and the complex electrochemistry of the sulfur *** this research,a novel sulfur-based battery has been proposed that eliminates the need for metallic lithium anodes and other critical raw materials like cobalt and graphite,replacing them with biomass-derived *** approach presents numerous benefits,encompassing ample availability,cost-effectiveness,safety,and environmental *** particular,two types of biochar-based anode electrodes(non-activated and activated biochar)derived from spent common ivy have been investigated as alternatives to metallic *** compared their structural and electrochemical properties,both of which exhibited good compatibility with the typical electrolytes used in sulfur ***,while steam activation results in an increased specific surface area,the non-activated ivy biochar demonstrates better performance than the activated biochar,achieving a stable capacity of 400 mA h g^(−1)at 0.1 A g^(−1)and a long lifespan(>400 cycles at 0.5 A g^(−1)).Our results demonstrate that the presence of heteroatoms,such as oxygen and nitrogen positively affects the capacity and cycling performance of the *** led to increased d-spacing in the graphitic layer,a strong interaction with the solid electrolyte interphase layer,and improved ion ***,the non-activated biochar was successfully coupled with a sulfur cathode to fabricate lithium-metal-free sulfur batteries,delivering a specific energy density of~600 Wh kg^(−1).

关键词： activated biochar biochar electrochemical performance functional groups lithium-metal-free sulfur batteries

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Numerical Simulation of Turbulent diffusion Flames of a Biogas Enriched with Hydrogen

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Fluid dynamics & Materials Processing 2024年第1期20卷 79-96页

作者： Naima Krarraz Amina Sabeur Khadidja Safer ahmed Ouadha Laboratoire des Science et Ingénierie Maritimes Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie d’Oran Mohamed BoudiafOranAlgérie Laboratoire des Carburants Gazeux et de l’Environnement Facultéde Génie MécaniqueUniversitédes Sciences et de la Laboratoire des Carburants Gazeux et de l’Environneme

Any biogas produced by the anaerobic fermentation of organic materials has the advantage of being an environmentally friendly ***,the relatively low calorific value of such gases makes their effective utilization in practical applications relatively *** present study considers the addition of hydrogen as a potential solution to mitigate this *** particular,the properties of turbulent diffusion jet flames and the related pollutant emissions are investigated numerically for different operating *** related numerical simulations are conducted by solving the RANS equations in the frame of the Reynolds Stress Model in combination with the flamelet *** effects are also taken into account and the combustion kinetics are described via the GRI-Mech 3.0 reaction *** considered hydrogen fuel enrichment spans the range from 0%to 50%in terms of *** varies between 1 and 10 *** results show that both hydrogen addition and pressure increase lead to an improvement in terms of mixing quality and have a significant effect on flame temperature and *** also reduce CO_(2) emissions but increase NOx *** NO is shown to be the predominant NO formation mechanism.

关键词： Biogas hydrogen diffusion flame turbulence NO formation route pressure

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Influence of Various Earth-Retaining Walls on the dynamic Response Comparison Based on 3d Modeling

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2835-2863页

作者： Muhammad Akbar Huali Pan Jiangcheng Huang Bilal ahmed Guoqiang Ou Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu610000China Institute of International Rivers and Eco-Security Yunnan UniversityKunming650500China department of Structural Engineering Faculty of Civil EngineeringDoctoral SchoolAkademicka 2Silesian University of TechnologyGliwice44-100Poland

The present work aims to assess earthquake-induced earth-retaining(ER)wall *** study is on the dynamics analysis of various earth-retaining wall designs in hollow precast concrete panels,reinforcement concrete facing panels,and gravity-type earth-retaining *** finite element(FE)simulations utilized a 3d plane strain condition to model full-scale ER walls and numerous nonlinear dynamics *** seismic performance of differentmodels,which includes reinforcement concrete panels and gravity-type and hollowprecast concrete ER walls,was simulated and examined using the FE *** also displays comparative studies such as stress distribution,deflection of the wall,acceleration across the wall height,lateral wall displacement,lateral wall pressure,and backfill plastic *** components of the created ER walls were found throughout this research *** is a granular reinforcement backfill,while the other is a wall-facing panel and base *** dynamic response effects of varied earth-retaining walls have also been *** was discovered that the facing panel of the model significantly impacts the earthquake-induced displacement of ER *** proposed analytical model’s validity has been evaluated and compared with the reinforcement concrete facing panels,gravity-type ER wall,scientifically available data,and American Association of State Highway and Transportation Officials(AASHTO)guidelines results based on FE *** results of the observations indicate that the hollow prefabricated concrete ER wall is the most feasible option due to its lower displacement and high-stress distribution compared to the two *** methodology and results of this study establish standards for future analogous investigations and professionals,particularly in light of the increasing computational capabilities of desktop computers.

关键词： Seismic analysis finite element modeling earth-retaining ER walls dynamic response structural resilience

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