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Simultaneous nitrification and autotrophic denitrification in fluidized bed reactors using pyrite and elemental sulfur as electron donors

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Water Science and Engineering 2023年第2期16卷 143-153页

作者： Maria f.Carboni Sonia Arriaga Piet n.L.Lens national University of Ireland Galway H91 TK33 GalwayIreland Instituto Potosino de Investigación Científica y Tecnológica 78216 San Luis PotosíMexico

In this study, simultaneous nitrification and autotrophic denitrification (SnAD) with either elemental sulfur or pyrite were investigated in fluidized bed reactors in mesophilic conditions. The reactor performance was evaluated at different ammonium (12-40 mg/L of nH4+-n), nitrate (35-45 mg/L of nO3--n), and dissolved oxygen (DO) (0.1-1.5 mg/L) concentrations, with a hydraulic retention time of 12 h. The pyrite reactor supported the SnAD process with a maximum nitrogen removal efficiency of 139.5 mg/(L·d) when the DO concentration was in the range of 0.8-1.5 mg/L. This range, however, limited the denitrification efficiency of the reactor, which decreased from 90.0% ± 5.3% in phases II-V to 67.9% ± 7.2% in phases VI and VII. Sulfate precipitated as iron sulfate (feSO4/fe2(SO4)3) and sodium sulfate (na2SO4) minerals during the experiment. The sulfur reactor did not respond well to nitrification with a low and unstable ammonium removal efficiency, while denitrification occurred with a nitrate removal efficiency of 97.8%. In the pyrite system, the nitrifying bacterium nitrosomonas sp. was present, and its relative abundance increased from 0.1% to 1.1%, while the autotrophic denitrifying genera Terrimonas, ferruginibacter, and Denitratimonas dominated the community. Thiobacillus, Sulfurovum, and Trichlorobacter were the most abundant genera in the sulfur reactor during the entire experiment.

关键词： Pyrite Elemental sulfur Simultaneous nitrification and denitrification nitrogen removal 16S rRnA

Opportunities and challenges of biodegradable Zn-based alloys

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Journal of Materials Science & Technology 2020年第11期42卷 136-138页

作者： H.f.Li Z.Z.Shi L.n.Wang Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing100083China

following the footsteps of biodegradable Mg-based and fe-based alloys,biodegradable Zn-based alloy is a newcomer and rising star in the family of biodegradable metals and *** combined superior mechanical properties,appropriate degradation rates,excellent biocompatibility of biodegradable Zn-based alloys have brought worldwide research interest on the design,development and clinical translation of Zn-based *** present perspective has summarized opportunities and challenges in the development of biodegradable Zn-based alloys.

关键词： Biodegradable Zn-based alloys Clinical applications Mechanical properties Degradation behavior Biocompatibility Corrosion fatigue Bio-tribocorrosion

nutrient-hormone relations:Driving root plasticity in plants

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Molecular Plant 2022年第1期15卷 86-103页

作者： Zhongtao Jia Ricardo f.H.Giehl nicolaus von Wirén Molecular Plant nutrition Department of Physiology&Cell BiologyLeibniz Institute of Plant Genetics and Crop Plant Research(IPK)Corrensstr.306466 Stadt SeelandOT GaterslebenGermany

Optimal plant development requires root uptake of 14 essential mineral elements from the *** the bioavailability of these nutrients underlies large variation in space and time,plants must dynamically adjust their root architecture to optimize nutrient access and *** information on external nutrient availability and whole-plant demand is translated into cellular signals that often involve phytohormones as intermediates to trigger a systemic or locally restricted developmental *** and extent of such local root responses depend on the overall nutritional status of the plant that is transmitted from shoots to roots in the form of phytohormones or other systemic long-distance *** integration of these systemic and local signals then determines cell division or elongation rates in primary and lateral roots,the initiation,emergence,or elongation of lateral roots,as well as the formation of root ***,we review the cascades of nutrient-related sensing and signaling events that involve hormones and highlight nutrient-hormone relations that coordinate root developmental plasticity in plants.

关键词： root development root plasticity nutrient sensing nutrient signaling plant hormones nutrient use efficiency

Phasor-domain Dynamic Model of Asymmetric Current Injection Controller for Converter-interfaced Generator

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1269-1278页

作者： Victor A.f.Almeida Glauco n.Taranto José M.T.Marinho Electrical Engineering Department of the federal University of Rio de Janeiro(COPPE/UfRJ) Petrobras S.A.

This paper presents a controller model of asymmetric current injection for converter-interfaced generators suitable for root-mean-square(RMS)phasor-domain,fundamentalfrequency,three-phase,and dynamic simulation *** effectiveness of the proposed controller is assessed with simulations in test systems with high percentage of converter-interfaced *** simulations focus on the operation of protection relays that use negative-sequence quantities in their directional *** paper also presents and compares two strategies to limit reactive negative-sequence currents,and active and reactive positive-sequence currents.A tutorial test system and a regional system part of the actual Brazilian Interconnected Power System are used to assess the correctness of the proposed controller in three-phase fundamental-frequency RMS dynamic simulations.

关键词： Converter-interfaced generator three-phase model power system protection negative-sequence current injection negative-sequence current protection unbalanced fault three-phase root-mean-square(RMS)dynamic simulation

Experimental study on microstructural and corrosion behaviors of friction stir processed steel with CoCrfeCuTi HEA reinforcement and effect of annealing

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Science China Technological Sciences 2025年第1期 233-250页

作者： S.Aravind KRISHnA n.RADHIKA Alokesh PRAMAnIK n.JEYAPRAKASH Department of Mechanical Engineering Amrita School of EngineeringAmrita Vishwa Vidyapeetham School of Civil and Mechanical Engineering Curtin University School of Mechanical and Electrical Engineering China University of Mining and Technology

The ability to perform against extreme corrosion environments in stainless steel depreciates under challenging conditions in industrial applications. This can be resolved by employing surface modification techniques to modify the surface with the required characteristics. The present study investigates the outcomes of friction stir processing of SS304 with CoCrfeCuTi high entropy alloy(HEA) as reinforcement and the property enhancements post-annealing. The synthesized CoCrfeCuTi HEA exhibited irregular fragments with 17 μm mean particle size and body centred cubic(BCC) phase. The microstructure of the processed surface revealed ultra-refined grains with a uniform distribution of HEA filler. The microstructures of the samples annealed at 400℃, 550℃, 700℃ and 850℃ for 2 h also showed significant grain growth and grain refinements. The processed sample with HEA reinforcement annealed at 700℃ exhibited enhanced microhardness and tensile strength by 63% and 0.88 times than that of the processed sample with HEA pre-annealing. The subsequent electrochemical corrosion test displayed better corrosion resistance for the HEA-processed and annealed sample. Hot corrosion tests at 900℃ showcased excellent resistance for the HEA processed and annealed samples by 14.92%, 12.75%, and 14.83% against the samples pre-annealed under three different salt mixtures, and the corroded surface was analyzed.

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Li(2p←2s)+na(3s)pressure broadening in the far-wing and line-core profiles

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Chinese Physics B 2022年第7期31卷 247-254页

作者： f Talbi n Lamoudi L Reggami M T Bouazza K Alioua M Bouledroua Physics Department Badji Mokhtar UniversityB.P.12Annaba 23000Algeria Laboratoire de Physique des Rayonnements Badji Mokhtar UniversityB.P.12Annaba 23000Algeria Laboratoire d’Etude des Surfaces et Interfaces de la Matiere Solide(LESIMS) Badji Mokhtar UniversityB.P.12 Annaba 23000Algeria Laboratoire LAMA Laboratoire des Materiaux Avances(LAMA)Badji Mokhtar UniversityB.P.12 Annaba 23000Algeria Laboratoire de Physique de la Matiere et du Rayonnement LPMR Universite Cherif MessaidiaB.P.1553Souk-Ahras 41000Algeria

This work reports pressure-broadening line-wing and line-core of the lithium Li(2p←2s)resonance line perturbed by ground sodium na(3s)*** far-wing regions,the calculations are performed quantum-mechanically and are intended to examine the photoabsorption coefficients at diverse *** results show the existence of three satellites,in the blue wing near the wavelengths 470 nm and in the red wing around 862 nm and 1070 *** the line-core region,by adopting the simplified Baranger model,the line-width and line-shift rates are determined,and their variation law with temperature is *** published data were found to compare these results with.

关键词： pressure broadening line-core broadening far-wing spectra photoabsorption

The effect of K2Sif6 on the MgH2 hydrogen storage properties

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Journal of Magnesium and Alloys 2020年第3期8卷 832-840页

作者： M.Ismail M.S.Yahya n.A.Sazelee n.A.Ali f.A.Halim Yap n.S.Mustafa Energy Storage Research Group Faculty of Ocean Engineering Technology and InformaticsUniversity Malaysia Terengganu21030 Kuala TerengganuMalaysia faculty of Innovative Design and Technology Universiti Sultan Zainal AbidinGong Badak Campus21300 Kuala NerusTerengganuMalaysia

The catalytic effect of K2Sif6 on MgH2 was first timely *** MgH2+5 wt.%K2Sif6 was prepared via the ball milling *** catalyst had lessened the initial decomposition temperature by 134℃ and 48℃ as compared to both pristine and milled MgH2 samples,*** 2 minutes,4.5 wt.%of hydrogen was absorbed(250℃)by the doped composite,which was 0.8 wt.%higher than the milled ***,for the desorption kinetics(320℃,1 atm),the amount of desorbed hydrogen was increased by 2.4 wt.%and 2.3 wt.%for the first 10 and 20 ***,contracting volume and Johnson-Mehl-Avrami models were used to analyse the kinetics *** decomposition activation energy calculated based on Kissinger equation was 114 kJ/*** for the active species,Mg2Si,Mgf2 and KH were formed during the heating *** active species are speculated to be responsible for the improvement of the hydrogenation properties of the composite.

关键词： Catalytic effect Magnesium hydride Hydrogen storage Sorption properties Contracting volume model

Inter-relationship of Various Results in Analysis of （14.0 MeV／U） Pb＋Pb Reaction Using Mica and Cn-85 Track Detectors

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Chinese Physics Letters 2005年第1期22卷 69-71页

作者： f.n.Khattak E.U.Khan Tabassumnasir J.J.Baluch f.U.Khan U.W.C. GomalUniversityDeraIsmailKhanPakistan RadiationPhysicsDivision PINSTECHNiloreIslamabadPakistan DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan

Two detector materials mica and cellulose-nitrate(Cn)-85 have been used to study (14.0MeV/u) Pb + Pb reaction. Events of different multiplicities were registered in mica and Cn-85 detectors using the 2π-geometry technique of solid state nuclear track detection. After removing the target material from the detectors the damaged trails in the detectors were revealed as tracks by proper chemical etching. The irradiated area of each sample was scanned and events of different multiplicities were traced. The binary events were bifurcated into elastic and inelastic events. The elastic binary events and three prong events, observed in the reaction, have been used to search out coefficients Cμν in the presence of both the detectors, for the reaction under study. Using these coefficients 3- and 4-prong events have been analysed. from the detailed analysis of the results of (14.0MeV/u) Pb+Pb reaction, obtained from mica and Cn-85 track detectors we observed a great resemblance of results obtained from the two detectors. Combining the results of both the detectors, we report some important outcomes.

关键词： Cn-85轨迹探测器高能物理学铅原子碰撞反应固态

Replication of natural surface topographies to generate advanced cell culture substrates

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Bioactive Materials 2023年第10期28卷 337-347页

作者： n.O.Monteiro J.f.fangueiro R.L.Reis n.M.neves 3B’s Research Group I3Bs-Research Institute on BiomaterialsBiodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAveParkParque de Ciencia e Tecnologi1Zona Industrial da Gandr14805-017BarcoGuimaraesPortugal ICVS/3B’s-PT Government Associate Laboratory Brag1Guimar˜aesPortugal

Surface topographies of cell culture substrates can be used to generate in vitro cell culture environments similar to the in vivo cell niches. In vivo, the physical properties of the extracellular matrix (ECM), such as its topography, provide physical cues that play an important role in modulating cell function. Mimicking these properties remains a challenge to provide in vitro realistic environments for cells. Artificially generated substrates’ topographies were used extensively to explore this important surface cue. More recently, the replication of natural surface topographies has been enabling to exploration of characteristics such as hierarchy and size scales relevant for cells as advanced biomimetic substrates. These substrates offer more realistic and mimetic environments regarding the topographies found in vivo. This review will highlight the use of natural surface topographies as a template to generate substrates for in-vitro cell culture. This review starts with an analysis of the main cell functions that can be regulated by the substrate’s surface topography through cell-substrate interactions. Then, we will discuss research works wherein substrates for cell biology decorated with natural surface topographies were used and investigated regarding their influence on cellular performance. At the end of this review, we will highlight the advantages and challenges of the use of natural surface topographies as a template for the generation of advanced substrates for cell culture.

关键词： Biomimetic topography Cell culture substrates natural surface topographies