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Environmental investigation of bio-modification of steel slag through microbially induced carbonate precipitation

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Journal of Environmental Sciences 2021年第3期33卷 282-292页

作者： Junke Zhang Peidong Su yadong Li lin li Department of Civil and Environmental Engineering Jackson State UniversityJacksonMS 39217United States Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental ScienceChinese Academy of SciencesBeijing 100085China Department of Civil and Architectural Engineering Tennessee State UniversityNashvilleTN 37209United States

Steel slag(SS)is one of byproduct of steel manufacture industry.The environmental concerns of SS may limit their re-use in different applications.The goal of this study was to investigate the leaching behavior of metals from SS before and after treated by microbially induced carbonate precipitation(MICP).Toxicity characteristic leaching procedure,synthetic precipitation leaching procedure and water leaching tests were performed to evaluate the leaching behavior of major elements(Fe,Mg and Ca)and trace elements(Ba,Cu and Mn)in three scenarios.The concentrations of leaching metals increased with the content of SS.After it reached the peak concentration,the leaching concentration decreased with the content of SS.The leachability of all elements concerned in this study was below 0.5%.The carbonate generated from the MICP process contributed to the low leachability of metals.After bio-modified by MICP process,the leaching concentrations of Ba from TCLP,SPLP and WLT tests were below 2.0 mg/L,which was the limit in drinking water regulated by U.S.EPA.The concentrations of Cu leached out from MICP-treated SS-sand samples were below 1.3 mg/L which is the limit regulated by national secondary drinking water.Compared with the regulations of U.S.EPA and Mississippi Department of Environment Quality(MDEQ),MICP-treated samples were classified as non-hazardous materials with respects to the leaching of metals.Meanwhile,maximum contaminant limits regulated by U.S.EPA states that MICP-treated SS are eco-friendly materials that can be reused as construction materials.

关键词： Biomodification Microbially-induced carbonate precipitation Metal leaching behavior Bioleaching Pearson correlation

Chemical fixation of toxic metals in stainless steel pickling residue by Na2S·xH2O,FeSO4·6H2O and phosphoric acid for beneficial uses

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Journal of Environmental Sciences 2020年第4期32卷 364-374页

作者： Peidong Su Junke Zhang yadong Li Department of Civil&Environmental Engineering Jackson State UniversityJacksonMS39217USA

The leaching concentrations of different metals in stainless steel pickling residue(SSPR)were determined and the toxic metals were treated using Na2 S·xH2 O,FeSO4·6 H2 O,and phosphoric acid.A modified European Community Bureau of Reference(BCR)sequential extraction was used to identify the speciation of the concerned metals.Results showed that SSPR contains a large amount of Ca(58.41%),Fe(29.44%),Cr(3.83%),Ni(2.94%),Mn(2.82%)and some of Al,Cu,Mg,Zn.Among them,Cr and Ni were the most toxic metals in SSPR,thus the raw SSPR falls into hazardous waste category due to the leaching amount of Cr.In addition,the leached Cr was identified as Cr6+(MgCr04)in the waste.BCR test revealed that risk assessment code(RAC)of Cr and Ni were 33.29%and 61.7%,indicating they posed"high"and"very high"risk to the environment,respectively.After fixing by Na2 S·xH2 O and FeSO4·6 H2 O,the leaching concentrations of Cr and Ni were less than 1.5 and 0.5 mg/L,respectively.After fixing by Na2 S·xH2 O and FeSO4·6 H2 O the tre ated SSPR can be safely reused as roadbed materials,concrete and cement aggregates.This study provides a useful implication in treatment and beneficial reuse of heavy metal-containing hazardous wastes.

关键词： Stainless steel pickling residue Leaching toxicity Cr(Ⅵ) Chemical fixation Beneficial reuses

A literature review of MOF derivatives of electromagnetic wave absorbers mainly based on pyrolysis

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International Journal of Minerals,Metallurgy and Materials 2023年第3期30卷 446-473页

作者： Qiuyi Wang Jie liu yadong Li Zhichao Lou Yanjun li Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry UniversityNanjing 210037China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037China Henan Science&Technology Exchange Center with Foreign Countries Zhengzhou 450000China College of Engineering University of GeorgiaAthens 30605USA

Growing electromagnetic pollution has plagued researchers in the field of electromagnetic(EM)energy dissipation for many years;it is increasingly important to solve this problem efficiently.Metal-organic frameworks(MOFs),a shining star of functional materials,have attracted great attention for their advantages,which include highly tunable porosity,structure,and versatility.MOF-derived electromagnetic wave(EMW)absorbers,with advantages such as light weight,thin matching thickness,strong capacity,and wide effective bandwidth,are widely reported.However,current studies lack a systematic summary of the ternary synergistic effects of the precursor component-structure-EMW absorption behavior of MOF derivatives.Here we describe in detail the electromagnetic(EM)energy dissipation mechanism and strategy for preparing MOF-derived EMW absorbers.On the basis of this description,the following means are suggested for adjusting the EM parameters of MOF derivatives,achieving excellent EM energy dissipation:(1)changing the metal and ligands to regulate the chemical composition and morphology of the precursor,(2)controlling pyrolysis parameters(including temperature,heating rate,and gas atmosphere)to manipulate the structure and components of derivatives,and(3)compounding with enhancement phases,including carbon nanomaterials,metals,or other MOFs.

关键词： metal organic framework microstructure magnetic-dielectric synergy electromagnetic wave absorption

Single-atom catalysis for carbon neutrality

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Carbon Energy 2022年第6期4卷 1021-1079页

作者： ligang Wang Dingsheng Wang yadong Li Department of Chemistry Tsinghua UniversityBeijingChina

Currently,more than 86%of global energy consumption is still mainly dependent on traditional fossil fuels,which causes resource scarcity and even emission of high amounts of carbon dioxide(CO_(2)),resulting in a severe“Greenhouse effect.”Considering this situation,the concept of“carbon neutrality”has been put forward by 125 countries one after another.To achieve the goals of“carbon neutrality,”two main strategies to reduce CO_(2) emissions and develop sustainable clean energy can be adopted.Notably,these are crucial for the synthesis of advanced single-atom catalysts(SACs)for energyrelated applications.In this review,we highlight unique SACs for conversion of CO_(2) into high-efficiency carbon energy,for example,through photocatalytic,electrocatalytic,and thermal catalytic hydrogenation technologies,to convert CO_(2) into hydrocarbon fuels(CO,CH_(4),HCOOH,CH_(3)OH,and multicarbon[C_(2+)]products).In addition,we introduce advanced energy conversion technologies and devices to replace traditional polluting fossil fuels,such as photocatalytic and electrocatalytic water splitting to produce hydrogen energy and a high-efficiency oxygen reduction reaction(ORR)for fuel cells.Impressively,several representative examples of SACs(including d-,ds-,p-,and f-blocks)for CO_(2) conversion,water splitting to H2,and ORR are discussed to describe synthesis methods,characterization,and corresponding catalytic activity.Finally,this review concludes with a description of the challenges and outlooks for future applications of SACs in contributing toward carbon neutrality.

关键词： carbon neutrality CO_(2)reduction reaction single-atom catalysts sustainable clean energy

Emerging low-nuclearity supported metal catalysts with atomic level precision for efficient heterogeneous catalysis

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Nano Research 2022年第9期15卷 7806-7839页

作者： Xiaobo Zheng Beibei li Qishun Wang Dingsheng Wang yadong Li Department of Chemistry Tsinghua UniversityBeijing 100084China

Supported atomically dispersed metal catalysts(ADMCs)have received enormous attention due to their high atom utilization efficiency,mass activity and excellent selectivity.Single-atom site catalysts(SACs)with monometal-center as the quintessential ADMCs have been extensively studied in the catalysis-related fields.Beyond SACs,novel atomically dispersed metal catalysts(NADMCs)with flexible active sites featuring two or more catalytically centers including dual-atom and triple-atom catalysts have drawn ever-increasing attention recently.Owing to the presence of multiple neighboring active sites,NADMCs could exhibit much higher activity and selectivity compared with SACs,especially in those complicated reactions with multi-step intermediates.This review comprehensively outlines the recent exciting advances on the NADMCs with emphasis on the deeper understanding of the synergistic interactions among multiple metal atoms and underlying structure-performance relationships.It starts with the systematical introduction of principal synthetic approaches for NADMCs highlighting the key issues of each fabrication method including the atomically precise control in the design of metal nuclearity,and then the state-of-the-art characterizations for identifying and monitoring the atomic structure of NADMCs are explored.Thereafter,the recent development of NADMCs in energy-related applications is systematically discussed.Finally,we provide some new insights into the remaining challenges and opportunities for the development of NADMCs.

关键词： dual-atom catalysts atomically precise control synthesis strategy synergistic interactions structure-performance relationships

Synthetic Jet Control on the Propulsion Behavior of a Foil in Plunge-pitch Motion

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Journal of Bionic Engineering 2020年第2期17卷 303-314页

作者： yadong Li Guoqing Zhou Jie Wu liaoning General Aviation Academy Shenyang Aerospace UniversityShenyang 110136China College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The Synthetic Jet(S J)control on the propulsion behavior of a foil in plunge-pitch motion is examined in this work by numerical simulations.An elliptic foil with ratio of 8 performs the plunge and pitch motions synchronously.A pair of SJs with the same frequency and strength is integrated into the upper and lower surfaces of the foil.As a result,the local flow field around the foil could be obviously modified by the SJs.At the Reynolds number of 200,the effects of the inclined angle between the jet direction and the chord line,the phase angle between the SJs and the flapping motion as well as the location of SJ on the propulsion performance are systematically investigated.Compared with the pure plunging and pitching foil,it is indicated that the enhancement of mean thrust and propulsive efficiency can be obtained by the SJs with suitable working parameters.Based on the numerical analysis,it is found that the jet flow on the foil surfaces,which changes the local pressure distribution to increase the pressure difference between upper and lower surfaces,can benefit the propulsion behavior of the flapping foil.

关键词： propulsion behavior plunge-pitch motion elliptic foil synthetic jet

Perfectly planar CoB^-18 as a motif for metallo-borophenes

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Nano Research 2016年第7期9卷 1877-1878页

作者： yadong Li Department of Chemistry and Collaborative Innovation Center for Nanomaterials Science and Engineering Tsinghua University Beijing 100084 China

Over the past decade, extensive collaborative experimental and theoretical researches have systematically elucidated the structures and chemical bonding of boron clusters as a function of size and have revealed an intriguing set of structures, ranging from planar hydrocarbon-analogs to nanotubular and fullerenelike structures （borospherenes） [1-7]. Small boron clusters have the propensity for planarity with delocalized σ and π electrons over the whole molecular plane, giving rise to the concept of multiple aromatidty.

关键词： Perfectly CoB_(18)~- metallo-borophenes

A nonlinear equalization for a PAM4 IM/DD system using MZM

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Optoelectronics Letters 2022年第4期18卷 238-242页

作者： li li liU Ran SUN yadong College of Communication Engineering Jilin UniversityChangchun 130012China

The nonlinear distortion caused by the Mach-Zehnder modulator(MZM)is one of the main limiting factors for the improvement of the transmission performance of the intensity modulation and direct detection(IM/DD)optical communication system.In order to solve the problem,an improved Volterra nonlinear equalization(VNLE)method is proposed.Compared with the traditional VNLE that uses the least mean square(LMS)to calculate the tap coefficients,the improved VNLE uses the least square(LS)method to obtain more stable convergence.The simulation results show that the VNLE based on LS has better performance when solving complex nonlinear damage.For 25 Gbaud 4-level pulse amplitude modulation(PAM4)signals,the improved VNLE can reduce the bit error rate(BER)to below 10^(-4) in a 7-km-long single-mode optical fiber transmission system.In addition,in order to make the BER below 10^(-3),the transmission distance that the improved VNLE can withstand is about 1.5 km longer than that of the traditional VNLE.

关键词： convergence nonlinear limiting

Process analysis of temperature swing adsorption and temperature vacuum swing adsorption in VOCs recovery from activated carbon

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Chinese Journal of Chemical Engineering 2023年第1期53卷 346-360页

作者： yadong Li Yuanhui Shen Zhaoyang Niu Junpeng Tian Donghui Zhang Zhongli Tang Wenbin li Collaborative Innovation Center of Chemical Science and Engineering The Research Center of Chemical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

In order to better guide the design of industrial process for purification and recovery of VOCs,temperature swing adsorption(TSA)and temperature vacuum swing adsorption(TVSA)process for VOCs purification and recovery were studied systematically with activated carbon adsorbent.The adsorption and desorption behaviors of benzene on activated carbon in above two processes were investigated systematically.Effects of operating parameters on process performances were further analyzed,including as regeneration temperature,purging feed ratio and hot–cold purging ratio.The results showed that the increase of hot–cold purging ratio(HP/CP)could obtain the same regeneration effect as the increase of desorption temperature.Increasing the feed purge ratio without increasing the hot–cold purging ratio is not conducive to bed regeneration,because a large number of cold purge gases cannot utilize the residual heat of temperature wave,thus reducing the desorption effect of the cooling step on the bed.In addition,the vacuum step can enhance the regeneration ability of hot nitrogen to the bed at the same regeneration temperature,making the bed regeneration of TVSA process more thorough.Temperature in the middle and lower part of the bed in TVSA process was higher and the regeneration was more thorough.In conclusion,TVSA has more obvious advantages than TSA in terms of energy consumption,hot or cold purge volume and bed regeneration.

关键词： VOCs TSA TVSA Activated carbon Benzene