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Effect of residual dissolved oxygen on the corrosion behavior of low carbon steel in 0.1 M NaHCO3 solution

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Journal of Materials Science & Technology 2018年第8期34卷 1349-1358页

作者： Fang Xue Xin Wei Junhua Dong ini-Ibehe Nabuk Etim Changgang Wang Wei Ke Institute of Metal Research Chinese Academy of SciencesShenyang 110016China University of Science and Technology of China Hefei 230026China

The effect of residual dissolved oxygen （DO） on the corrosion behavior of carbon steel in 0.1 M NaHCO3 solution was investigated by electrochemical measurements, corrosion mass loss test, scanning electron microscopy （SEM） and X-ray diffraction （XRD）. In the initial immersion stage, the increase of the dissolved oxygen concentration led to the change of from a reductive state of active dissolution to an oxidizing state of pseudo passivation in low carbon steel. While in the final stage, all the steels transformed into the steady state of pseudo passivation. In the anaerobic solution, the formation of c^-FeOOH was attributed to the chemical oxidization of the ferrous corrosion products and the final cathodic process only included the reduction of c^-FeOOH, while in the aerobic solution, it included the reduction of oxygen and （x-FeOOH simultaneously. As the main corrosion products, the content of （x-FeOOH was increased while that of Fe6（OH）12CO3 was decreased with increasing concentration of dissolved oxygen. The total corrosion mass loss of the steel was promoted with the increase of dissolved oxygen concentration.

关键词： Low carbon steel Residual dissolved oxygen Electrochemical characterization Anodic dissolution state Pseudo passivation

Atomically precise M-N-C electrocatalysts for oxygen reduction:Effects of inter-site distance,metal-metal interaction,coordination environment,and spin states

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Journal of Energy Chemistry 2025年第2期101卷 132-155页

作者： Junfeng Huang Saira Ajmal Anuj Kumar Jianwen guo Mohammed Mujahid Alam Abdullah g.Al-Sehemi ghulam Yasin School of Mechanical Engineering Dongguan University of Technology Nano-Technology Research Laboratory Department of Chemistry GLA University Department of Chemistry College of Science King Khalid University School of Environmental Science and Engineering Tianjin University State Key Laboratory of Chemical Resource Engineering College of Materials Science and Engineering Beijing University of Chemical Technology

Inspired by molecular catalysts,researchers developed atomically precise nitrogen-coordinated single or dual metal sites imbedded in graphitized carbon（M-N-C） to fully utilize metallic sites for *** catalysts performed remarkably well in the electrocatalytic oxygen reduction reaction（ORR） due to their distinct coordination and electrical structures,Nonetheless,their maximum efficacy in practical applications has yet to be *** agenda identifies tailoring the coordination environment,spin states,intersite distance,and metal-metal interaction as innovative approaches to regulate the ORR performance of these ***,it is necessary to undertake a precise assessment of these methodologies and the knowledge obtained to be implemented in the design of future M-N-C catalysts for ***,this review aims to analyze recent progress in M-N-C ORR catalysts,emphasizing their innovative engineering with aspects such as alteration in intersite distance,metal-metal interaction,coordination environment,and spin ***,we critically discuss how to logically monitor the atomic structure,local coordination,spin,and electronic states of M-N-C catalysts to modulate their ORR *** have also highlighted the challenges associated with M-N-C catalysts and proposed suggestions for their future design and fabrication.

关键词： Activity descriptors Electrocatalysis M-N-C electrocatalysts ORR Spin states

Hybrid ecophysiological growth model for deciduous Populus tomentosa plantation in northern China

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FOREST ECOSYSTEMS 2025年第1期12卷 112-120页

作者： Salekin, Serajis Bloomberg, Mark Xi, Benye Liu, Jinqiang Liu, Yang Li, Doudou Mason, Euan g. Sc Res New Zealand Forest Res Inst Ltd Sc Res Ltd Rotorua 3046 New Zealand Univ Canterbury New Zealand Sch Forestry Christchurch 8140 New Zealand Beijing Forestry Univ State Key Lab Efficient Prod Forest Resources Beijing 100083 Peoples R China Beijing Forestry Univ Key Lab Silviculture & Forest Ecosyst Res Arid and Beijing 100083 Peoples R China Beijing Forestry Univ Minist Educ Key Lab Silviculture & Conservat Beijing 100083 Peoples R China Chinese Acad Med Sci Peking Union Med Coll Inst Med Plant Dev Beijing 100193 Peoples R China

Short rotation plantation forestry (SRF) is being widely adopted to increase wood production, in order to meet global demand for wood products. However, to ensure maximum gains from SRF, optimised management regimes need to be established by integrating robust predictions and an understanding of mechanisms underlying tree growth. Hybrid ecophysiological models, such as potentially useable light sum equation (PULSE) models, are useful tools requiring minimal input data that meet the requirements of SRF. PULSE models have been tested and calibrated for different evergreen conifers and broadleaves at both juvenile and mature stages of tree growth with coarse soil and climate data. Therefore, it is prudent to question: can adding detailed soil and climatic data reduce errors in this type of model? In addition, PULSE techniques have not been used to model deciduous species, which are a challenge for ecophysiological models due to their phenology. This study developed a PULSE model for a clonal Populus tomentosa plantation in northern China using detailed edaphic and climatic data. The results showed high precision and low bias in height (m) and basal area (m2 center dot ha-1) predictions. While detailed edaphoclimatic data produce highly precise predictions and a good mechanistic understanding, the study suggested that local climatic data could also be employed. The study showed that PULSE modelling in combination with coarse level of edaphic and local climate data resulted in reasonably precise tree growth prediction and minimal bias.

关键词： growth-yield model Populus species Hybrid ecophysiological modelling Deciduous trees Phenology

Relation between Mass and Radius of Exoplanets Distinguished by their Density

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Research in Astronomy and Astrophysics 2023年第6期23卷 47-55页

作者： alberto S.Betzler Joség.V.Miranda Centro de Ciência e Tecnologia em Energia e Sustentabilidade Universidade Federal do Recôncavo da BahiaFeira de SantanaBahia44.085-132Brazil Instituto de Fisica Universidade Federal da BahiaSalvadorBahia40.170-115Brazil

The formation of the solar system has been studied since the 18th century and received a boost in 1995 with the discovery of the first exoplanet,51 Pegasi *** investigations increased the number of confirmed planets to about5400 to *** possible internal structure and composition of these planets can be inferred from the relationship between planet mass and radius,*** have analyzed the M-R relation of a selected sample of iron-rock and ice-gas planets using a fractal approach to their *** application of fractal theory is particularly useful to define the physical meaning of the proportionality constant and the exponent in an empirical M-R power law in exoplanets,but this does not necessarily mean that they have an internal fractal *** M-R relations based on this sample are M=(1.46±0.08)R^(2.6±0.2)for the rocky population(3.6≤ρ≤14.3 g cm^(-3)),with 1.5≤M≤39M_(⊕),and M=(0.27±0.04)R^(2.7±0.2)for ice-gas planets(0.3≤ρ≤2.1 g cm^(-3))with 5.1≤M≤639 M_(⊕)(or■2 M_(J))and orbital periods greater than 10 *** M-R relations have in their density range a great predictive power for the determination of the mass of exoplanets and even for the largest icy moons of the solar *** average fractal dimension of these planets is D=2.6±0.1,indicating that these objects likely have a similar degree of heterogeneity in their densities and a nearly similar composition in each *** M-R diagram shows a"gap"between ice-gas and iron-rock *** gap is a direct consequence of the density range of these two *** empirically propose an upper mass limit of about 100 M_(⊕),so that an M-R relation for ice-gas planets in a narrow density range is defined by M∝R^(3).

关键词： planets and satellites:formation planets and satellites:terrestrial planets planets and satellites:gaseous planets

Atmospheric chemistry of trifluorodicarbonyls initiated by Cl atoms:Reactivity trends,mechanism,and acid formation yields

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Journal of Environmental Sciences 2025年第5期151卷 12-25页

作者： Pedro L.Lugo Vianni g.Straccia Cynthia B.Rivela Mariano A.Teruel María B.Blanco Laboratorio Universitario de Química y Contaminación del Aire(L.U.Q.C.A) Instituto de Investigaciones en Fisicoquímica de Córdoba(I.N.F.I.Q.C.)Dpto.de Fisicoquímica.Facultad de Ciencias QuímicasUniversidad Nacional de Córdoba.Ciudad Universitaria5000 CórdobaArgentina Institute for Atmospheric and Environmental Research University of WuppertalDE-42097 WuppertalGermany

Rate coefficients of the gas-phase reactions of Cl atoms with a series of fluorinated diketones(FDKs):CF_(3)C(O)CH_(2)C(O)CH_(3)(TFP),CF_(3)C(O)CH_(2)C(O)CH_(2)CH_(3)(TFH)and CF_(3)C(O)CH_(2)C(O)CH(CH_(3))2(TFMH),have been measured at(298±2)K and under atmospheric *** experiments were performed using the relative-rate method with a gC-FID detection *** different determinations and references used,the following rate coefficients were obtained(in cm3/(molecule·sec)):k_(4)(TFP+Cl)=(1.75±0.21)×10^(−10),k_(5)(TFH+Cl)=(2.05±0.23)×10^(−10),k_(6)(TFMH+Cl)=(2.71±0.34)×10^(−10).Reactivity trends of FDKs were discussed and Free Energy Relationships analysis was *** expression lgkOH=1.68 lgkCl+5.71 was obtained for the reactivity of the studied FDKs together with similar unsaturated VOCs with Cl and OH radicals Additionally,acetic acid(CH_(3)C(O)OH)and trifluoroacetic acid(CF_(3)C(O)OH)were positively identified and quantified as degradation products using in situ FTIR *** to the identified products,atmospheric chemical mechanisms were *** atmospheric implications of the studied reactions were assessed by the estimation of the tropospheric lifetimes of TFP,TFH,and TFMH concerning their reaction with Cl atoms to be 48,41,and 31 hours,*** relatively short residence in the atmosphere of the fluorocarbons studied will have a local/regional impact with restricted *** warming potential(gWP(20 yr))calculated for the studied fluoro diketones were 0.014,0.003 and 0.001 for TFP,TFH and TFMH,respectively with a negligible contribution to the greenhouse effect.

关键词： Fluorinated diketones Kinetics SPME-gC-FID FTIR in situ SAR Free energy relationships

Next-generation Desalination Membranes Empowered by Novel Materials:Where Are We Now?

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Nano-Micro Letters 2025年第4期17卷 308-331页

作者： Siqi Wu Lu Elfa Peng Zhe Yang Pulak Sarkar Mihail Barboiu Chuyang Y.Tang Anthony g.Fane Department of Civil Engineering The University of Hong KongPokfulamHong Kong SARPeople’s Republic of China Institut Européen des Membrane University of MontpellierENSCMCNRS UMR5635Place Eugène BataillonCC 04734095 MontpellierFrance UNESCO Centre for Membrane Science and Technology School of Chemical EngineeringThe University of New South Wales(UNSW)SydneyNSW 2052Australia

Membrane desalination is an economical and energy-efficient method to meet the current worldwide water ***,state-of-the-art reverse osmosis membranes are gradually being replaced by novel membrane materials as a result of ongoing technological *** novel materials possess intrinsic pore structures or can be assembled to form lamellar membrane channels for selective transport of water or solutes(e.g.,NaCl).Still,in real applications,the results fall below the theoretical predictions,and a few properties,including large-scale fabrication,mechanical strength,and chemical stability,also have an impact on the overall effectiveness of those *** view of this,we develop a new evaluation framework in the form of radar charts with five dimensions(i.e.,water permeance,water/NaCl selectivity,membrane cost,scale of development,and stability)to assess the advantages,disadvantages,and potential of state-of-the-art and newly developed desalination *** this framework,the reported thin film nanocomposite membranes and membranes developed from novel materials were compared with the state-of-the-art thin film composite *** review will demonstrate the current advancements in novel membrane materials and bridge the gap between different desalination *** this review,we also point out the prospects and challenges of next-generation membranes for desalination *** believe that this comprehensive framework may be used as a future reference for designing next-generation desalination membranes and will encourage further research and development in the field of membrane technology,leading to new insights and advancements.

关键词： Novel materials Desalination membranes Reverse osmosis Evaluation framework Separation performance

Strigolactone Analogs as Molecular Probes in Chasing the （SLs） Receptor/s： Design and Synthesis of Fluorescent Labeled Molecules

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Molecular Plant 2013年第1期6卷 113-127页

作者： Cristina Prandi Helena Rosso Beatrice Lace Ernesto g. Occhiatot alberto Oppedisano Silvia Tabasso gabriele alberto Marco Blangetti Dipartimento di Chimica-Universita di Torino via R Giuria 7 10127 Torino Italy Dipartimento di Scienze della Vita e Biologia dei Sistemi Viale Mattioli 25 10125 Torino Italy Dipartimento di Chimica 'Ugo Schiff' Universita di Firenze Via della Lastruccia 13 50019 Sesto Fiorentino (FI) Italy School of Chemistry and Chemical Biology University College Dublin Belfield Dublin 4 Ireland

Originally identified as allelochemicals involved in plant-parasite interactions, more recently, Strigolactones （SLs） have been shown to play multiple key roles in the rhizosphere communication between plants and mycorrhizal fungi. Even more recent is the hormonal role ascribed to SLs which broadens the biological impact of these relatively simple molecules. In spite of the crucial and multifaceted biological role of SLs, there are no data on the receptor（s） which bind（s） such active molecules, neither in the producing plants nor in parasitic weeds or AM fungi. Information about the putative receptor of SLs can be gathered by means of structural, molecular, and genetic approaches. Our contribution on this topic is the design and synthesis of fluorescent labeled SL analogs to be used as probes for the detection in vivo of the receptor（s）. Knowledge of the putative receptor structure will boost the research on analogs of the natural substrates as required for agricultural applications.

关键词： strigolactones parasitic weeds mycorrhizal fungi receptor fluorescence.

Electrochemical noise analysis on the pit corrosion susceptibility of biodegradable AZ31 magnesium alloy in four types of simulated body solutions

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Journal of Materials Science & Technology 2018年第10期34卷 1876-1884页

作者： changgang wang liping wu fang xue rongyao ma ini-ibehe nabuk etim xuehui hao junhua dong wei ke Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Magnesium alloys have been investigated as biodegradable implant materials since the last century. Non-uniform degradation caused by local corrosion limits their application, and no appropriate technology has been used in the research. In this study, electrochemical noise has been used to study the pit corrosion on magnesium alloy AZ31 in four types of simulated body solutions, and the data have been analyzed using wavelet analysis and stochastic theory. Combining these with the conventional polarization curves, mass loss tests and scanning electron microscopy, the electrochemical noise results implied that AZ31 alloy in normal saline has the fastest corrosion rate, a high pit initiation rate, and maximum pit growth probability. In Hanks＇ balanced salt solution and phosphate-buffered saline, AZ31 alloy has a high pit initiation rate and larger pit growth probability, while in simulated body fluid, AZ31 alloy has the slowest corrosion rate, lowest pit initiation rate and smallest pit growth probability.

关键词： Biodegradable magnesium alloy Electrochemical noise (EN) Pit corrosion susceptibilities Wavelet analysis Stochastic model

Intraguild predation and competitive displacement between Nesidiocoris tenuis and Dicyphus maroccanus, two biological control agents in tomato pests

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Insect Science 2017年第5期24卷 809-817页

作者： Nadia g. Salas gervassio Meritxell Perez-Hedo Maria g. Luna alberto Urbaneja Centro de Estudios Parasitol6gicos y de Vectores (CEPAVE -CCT La Plata- CONICET-UNLP) Boulevard 120 el 60 y 64 1900 La PlataArgentina Centro de Proteccion Vegetal y Biotecnologia Instituto Valenciano de Investigaciones Agrarias (IVlA) Unidad Asociada de Entomologia UJI-IVIA Carretera de Moncada - N&quera Km. 4.5 46113 Moncada Valencia Spain Unitat Associada d'Entomologia UJI-IVIA Departament de Ciencies Agr&ries i del Medi Natural Universitat Jaume I UJI Campus del Riu Sec E-12071 Castello de laPlana Spain

Dicyphus maroccanus Wagner and Nesidiocoris tenuis Reuter （Hemiptera： Miridae） are 2 biological control agents in tomatoes. Through the crop seasons, a natural shift in the occurrence of both mirids in favor ofN. tenuis has been observed at the end of the cropping cycle in eastern Spain. To better optimize their conservation, the reasons for the observed change, such as intraguild interactions （IgP） or the influence of environmental conditions, are worth elucidating. To do this, we first studied the IgP of adult females on heterospecific nymphs in the laboratory. We next studied exploitative competition between adults and nymphs of each species when feeding on Ephestia kueniella Zeller （Lepidoptera： Pyralidae） eggs in the laboratory. Finally, to analyze the competitive displacement between both mirids, we conducted a semifield experiment in which both predators were released together. All experiments were conducted at 2 temperature regimes （20 and 25~C）. Adult- to-nymph intraguild interactions occurred only at 25 ~C at very low levels, showing that N. tenuis attacked and consumed a greater proportion ofheterospecific nymphs. Nesidiocoris tenuis was a better competitor than D. maroccanus when feeding on the shared prey in the presence of its heterospecific nymph at 25 ~C. In semifield conditions, N. tenuis showed a competitive advantage over D. maroccanus at both temperatures. We conclude that there is not direct interference between both species, however, N. tenuis has a greater ability to outcompete, since it is best adapted to higher temperatures and it is able to remove food sources for D. maroccanus.

关键词： competition Mediterranean crops Miridae temperature tomato