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Ferrihydrite transformation impacted by coprecipitation of lignin:Inhibition or facilitation?

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Journal of Environmental Sciences 2024年第5期139卷 23-33页

作者： Lin Liu zhihui yang Weichun yang Wen Jiang Qi Liao Mengying Si Feiping Zhao School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution(CNERC-CTHMP) Changsha 410083China

Lignin is a common soil organic matter that is present in soils,but its effect on the transformation of ferrihydrite(Fh)remains *** matter is generally assumed to inhibit Fh ***,lignin can reduce Fh to Fe(Ⅱ),in which Fe(Ⅱ)-catalyzed Fh transformation ***,the effects of lignin on Fh transformation were investigated at 75℃ as a function of the lignin/Fh mass ratio(0-0.2),pH(4-8)and aging time(0-96 hr).The results of Fh-lignin samples(mass ratios=0.1)aged at different pH values showed that for Fh-lignin the time of Fh transformation into secondary crystalline minerals was significantly shortened at pH 6 when compared with pure Fh,and the Fe(Ⅱ)-accelerated transformation of Fh was strongly dependent on *** pH 6,at low lignin/Fh mass ratios(0.05-0.1),the time of secondary mineral formation decreased with increasing lignin *** high lignosulfonate-content material(lignin:Fh=0.2),Fh did not transform into secondary minerals,indicating that lignin content plays a major role in Fh *** addition,lignin affected the pathway of Fh transformation by inhibiting goethite formation and facilitating hematite *** effect of coprecipitation of lignin on Fh transformation should be useful in understanding the complex iron and carbon cycles in a soil environment.

关键词： Ferrihydrite transformation Lignin Hematite Goethite Fe(Ⅱ)-catalyzed Reactive Fe(Ⅲ)species

A multi-stream network for retrosynthesis prediction

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Frontiers of Computer Science 2024年第2期18卷 231-233页

作者： Qiang ZHANG Juan LIU Wen ZHANG Feng yang zhihui yang Xiaolei ZHANG Institute of Artificial Intelligence School of Computer ScienceWuhan UniversityWuhan 430072China College of Informatics Huazhong Agricultural UniversityWuhan 430072China

1 Introduction Retrosynthesis aims to predict a set of reactants for producing given molecules[1],which plays a significant part in the biochemistry field,such as molecular pathway design and drug *** existing methods perform better in solving this problem,most of these methods[2,3]only describe the molecules from one kind of perspective,such as they use Simplified Molecular Input Line Entry System(SMILES)strings[4]to represent the atomic components and the relationship between atoms of molecules or leverage Extended Connectivity Fingerprints(ECFPs)represent the information of the molecular sub-structure composition via binary vectors[5].

关键词： synthesis reactant hough

A review on the transformation of birnessite in the environment:Implication for the stabilization of heavy metals

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Journal of Environmental Sciences 2024年第5期139卷 496-515页

作者： Miao Shi Qingzhu Li Qingwei Wang Xuelei Yan Bensheng Li Linhai Feng Chao Wu Rongrong Qiu Hongkai Zhang zhihui yang Weichun yang Qi Liao Liyuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment ofHeavy Metal Pollution Central South UniversityChangsha 410083China Water Pollution Control Technology Key Lab of Hunan Province Changsha 410083China

Birnessite is ubiquitous in the natural environment where heavy metals are retained and easily *** surface properties and structure of birnessite change with the changes in external environmental conditions,which also affects the fate of heavy *** the effect and mechanism of the birnessite phase transition process on heavy metals is the key to taking effective measures to prevent and control heavy metal ***,the four transformation pathways of birnessite are summarized first in this ***,the relationship between transformation pathways and environmental conditions is *** relevant environmental conditions include abiotic(e.g.,co-existing ions,pH,oxygen pressure,temperature,electric field,light,aging,pressure)and biotic factors(e.g.,microorganisms,biomolecules).The phase transformation is achieved by the key intermediate of Mn(Ⅲ)through interlayer-condensation,folding,neutralizationdisproportionation,and dissolution-recrystallization *** AOS(average oxidation state)of Mn and interlayer spacing are closely correlated with the phase transformation of *** but not least,the mechanisms of heavy metals immobilization in the transformation process of birnessite are summed *** involve isomorphous substitution,redox,complexation,hydration/dehydration,*** transformation of birnessite and its implication on heavy metals will be helpful for understanding and predicting the behavior of heavy metals and the crucial phase of manganese oxides/hydroxides in natural and engineered environments.

关键词： Birnessite Transformation Heavy metals Pathways Mechanism

Trace Cobalt Doping and Defect Engineering of High Surface Area a-Ni（OH）2 for Electrocatalytic Urea Oxidation

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Energy & Environmental Materials 2024年第2期7卷 115-122页

作者： Yi Liu zhihui yang Yuqin Zou Shuangyin Wang Junying He School of Metallurgy and Environment Central South University State Key Laboratory of Chem/Bio-Sensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University

Owing to the intrinsically sluggish kinetics of urea oxidation reaction（UOR）involving a six-electron transfer process,developing efficient UOR electrocatalyst is a great challenge remained to be ***,by taking advantage of 2-Methylimidazole,of which is a kind of alkali in water and owns strong coordination ability to Co2+in methanol,trace Co（1.0 mol%） addition was found to induce defect engineering on α-Ni（OH）2in a dualsolvent system of water and *** characterization results revealed that the synthesized electrocatalyst(WM-Ni0.99Co0.01（OH）2) was a kind of defective nanosheet with thickness around 5-6 nm,attributing to the synergistic effect of Co doping and defect engineering,its electron structure was finely altered,and its specific surface area was tremendously enlarged from 68 to 172.3 *** all these merits,its overpotential to drive 10 mA cm-2was reduced by 110 ***,the interfacial behavior of UOR was also well deciphered by operando electrochemical impedance spectroscopy.

关键词： defect engineering electrocatalysis small molecule oxidation

基于接触区域自适应调整的圆弧头立铣刀后刀面磨削轨迹精确计算方法

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中国机械工程 2024年第7期35卷 1222-1231,1240页

作者：刘哲杨德存阳智麾江磊西南交通大学机械工程学院成都610031 东方电气集团东方汽轮机有限公司德阳618000

为保证圆弧头立铣刀后刀面的加工精度,提出一种基于接触区域自适应调整的圆弧头立铣刀后刀面磨削轨迹精确计算方法。通过圆弧头立铣刀结构特征分解构建了后刀面的数学模型;通过计算砂轮和后刀面之间的磨削接触区域,自适应修正砂轮姿态,... 详细信息

为保证圆弧头立铣刀后刀面的加工精度,提出一种基于接触区域自适应调整的圆弧头立铣刀后刀面磨削轨迹精确计算方法。通过圆弧头立铣刀结构特征分解构建了后刀面的数学模型;通过计算砂轮和后刀面之间的磨削接触区域,自适应修正砂轮姿态,避免磨削干涉,实现了后刀面几何参数控制的准确性和一致性,并保证了曲面的光滑连接。最后,在VC++平台算法模块开发的基础上,通过加工仿真和磨削试验验证了该算法的有效性。

关键词：圆弧头立铣刀后刀面磨削轨迹接触区域自适应调节

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环保交联水性聚氨酯油墨连结料的制备与性能

塑料 2024年第1期53卷 103-108,144页

作者：崔香杨智慧青海师范大学化学化工学院青海西宁810008

分别采用二官能度的2-[(2-氨基乙基)-氨基]乙基磺酸钠(A95)、多官能度的二亚乙烯三胺(DETA)和三亚乙烯四胺(TETA)作为扩链剂或交联剂,合成了3种水性聚氨酯(WPU)分散体。结果表明,DETA能显著提高WPU的相对分子质量、粘接性能及耐水性能... 详细信息

分别采用二官能度的2-[(2-氨基乙基)-氨基]乙基磺酸钠(A95)、多官能度的二亚乙烯三胺(DETA)和三亚乙烯四胺(TETA)作为扩链剂或交联剂,合成了3种水性聚氨酯(WPU)分散体。结果表明,DETA能显著提高WPU的相对分子质量、粘接性能及耐水性能。但是,单独采用DETA制备WPU的储存期较短(>4个月)。因此,利用A95与DETA的协同作用,采用不同摩尔比的A95/DETA(4:1、3:2、2:3、1:4)作为混合扩链剂(交联剂)制备了一系列WPU。结果显示,WPU分散体的固含量约为33%、pH=7~8、平均粒径为117.8~372.3 nm。当A95/DETA的摩尔比为2:3时,WPU具有较好的储存稳定性、粘接性能、力学性能、抗水抗油性能及较高的相分离程度。WPU制备在过程中仅需添加3%~4%的有机溶剂,可以直接用作水基油墨连结料,避免溶剂的回收,有利于工业化生产。

关键词：水性聚氨酯二亚乙烯三胺交联改性油墨连结料粘接性能

“双减”背景下小学生学习投入的潜在类别转变

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心理学报 2024年第3期56卷 295-310页

作者：杨靖渊于晓张婧漪卢骊霏杨智辉北京林业大学人文社会科学学院心理学系北京100083 北京师范大学心理学部北京100875 北京师范大学发展心理研究院北京100875

采用潜在转变分析考察“双减”背景下小学生学习投入的转变类别及其影响因素。研究以347名小学生为被试,对其“双减”实施前后的学习投入水平、父母积极教养方式、师生关系和同伴关系进行了纵向追踪。结果表明:(1)小学生学习投入存在“... 详细信息

采用潜在转变分析考察“双减”背景下小学生学习投入的转变类别及其影响因素。研究以347名小学生为被试,对其“双减”实施前后的学习投入水平、父母积极教养方式、师生关系和同伴关系进行了纵向追踪。结果表明:(1)小学生学习投入存在“低学习投入组”、“中等学习投入组”、“高专注低活力组”和“高学习投入组”四种不同类别;(2)“双减”政策实施后,“中等学习投入组”和“高学习投入组”稳定性较强,“低学习投入组”更易向“中等学习投入组”转变,在政策实施半年后,“高专注低活力组”学生更易向“中等学习投入组”转变,政策实施一年后,该组学生保持在“高专注低活力组”的概率较高;(3)父母积极教养方式、师生关系及同伴关系对“双减”政策前后小学生学习投入类别转变的预测作用存在差异。本研究不仅有助于深入理解小学生学习投入的发展变化及影响因素,还为“双减”政策的实施效果提供了实证证据。

关键词： “双减”政策潜在转变分析学习投入纵向研究小学生

磨削圆柱螺旋槽的砂轮轮廓及位姿快速计算方法

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工具技术 2024年第9期58卷 92-97页

作者：刘浩李勇阳智麾江磊西南交通大学机械工程学院

在立铣刀螺旋槽的数控磨削过程中,砂轮的安装位姿对螺旋槽的前角、芯径、槽宽等截形参数影响显著,进而影响刀具的切削性能。精确、高效求解砂轮位姿是螺旋槽磨削工艺的首要任务,目前大多采用迭代的优化计算方法,但存在计算模型的精度与... 详细信息

在立铣刀螺旋槽的数控磨削过程中,砂轮的安装位姿对螺旋槽的前角、芯径、槽宽等截形参数影响显著,进而影响刀具的切削性能。精确、高效求解砂轮位姿是螺旋槽磨削工艺的首要任务,目前大多采用迭代的优化计算方法,但存在计算模型的精度与效率不足的问题。基于此对模型进行分析研究,采用一种优化计算新方法,根据芯径形成机理,通过接触原理对砂轮与工件的相对位姿进行运动变换,得到能够预先保证芯径的位姿参数表达式,降低了位姿参数变量维度,从而提高计算效率;同时推导了前角、槽宽的解析表达式,以此为约束,采用数值优化算法可精确计算出砂轮位姿参数。通过仿真与磨削试验对算法进行验证。结果表明,所提算法可以较精确地计算出砂轮位姿参数,相比于预先设计值误差较小,且计算效率比迭代法高,具有较高的工程实用性。

关键词：磨削圆柱螺旋槽砂轮轮廓砂轮位姿

基于关系型T5和重排名解码的Text-to-SQL方法分析

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电子技术（上海） 2024年第4期53卷 78-80页

作者：杨智慧中国科学技术大学安徽230026

阐述针对Text-to-SQL任务,构建一个带有重排名解码模块的关系型T5模型。将关系感知的自我注意模块引入T5编码器,以此提高模型对各种关系结构的语义理解能力。在解码过程中,对PICARD获得的N-best列表引入重排名解码,可通过搜寻算法,检查... 详细信息

阐述针对Text-to-SQL任务,构建一个带有重排名解码模块的关系型T5模型。将关系感知的自我注意模块引入T5编码器,以此提高模型对各种关系结构的语义理解能力。在解码过程中,对PICARD获得的N-best列表引入重排名解码,可通过搜寻算法,检查列表中的每个预测实体名称是否在数据库中出现,以提高结果的选择正确性。

关键词：智能算法文本到SQL 语义解析关系图注意力网络