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Green Energy & Environment 2024年第1期9卷 114-125页

作者： Yang Zhou Qiang Zeng Hongyan He kejia wu Fuqiao Liu Xuehui Li School of Chemistry and Chemical Engineering The Guangdong Provincial Key Laboratory of Green Chemical Product TechnologyState Key Laboratory of Pulp and Paper EngineeringSouth China University of TechnologyGuangzhouGuangdong510640China CAS Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China

In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations.

关键词： Lignin model compounds β-O-4 dimers Electrochemical oxidation Oxidation mechanisms Substituent effect

Combination Mechanism and Enhanced Visible-Light Photocatalytic Activity and Stability of CdS/g-C3N4 Heterojunctions

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Journal of Materials Science & Technology 2017年第1期33卷 30-38页

作者： Huanyan Xu Licheng wu Liguo Jin kejia wu School of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China

In this study, CdS/g-C3N4 （CSCN） heterojunctions were in situ fabricated with a large amount of CdS nanoparticles anchored on g-C3N4 nanosheets, A wet chemical method was developed for the first time to determine the actual content of CdS in CSCN composites. X-ray diffraction （XRD）, Fourier transform infrared spectra （FFIR）, high-resolution transmission electron microscopy （HRTEM） and UV-vis diffuse reflectance spectra （DRS） were employed to characterize the composition, structure and optical prop- erty of CSCN composites. Based on the is0electric point （liP） analysis of g-C3N4, a conclusion was obtained on the combination mechanism between CdS nanoparticles and g-C3N4 nanosheets. The photocatalytic activity of CSCN composites was much better than those of individual CdS and g-C3N4 for the degrada- tion of azo dye Methyl Orange （MO） by 40 min adsorption in the dark followed by 15 min photocatalysis under visible light irradiation. After 5 cycles, CSCN composites still maintained high reactive activity with the MO degradation efficiency of 93.8%, exhibiting good photocatalytic stability. The Cd2~ concentration dissolved in the supernatant detected by atomic absorption spectroscopy （AAS） of CSCN composites was lower than that of pure CdS, implying that the photocorrosion of CdS could be suppressed via the combination with g-C3N4. Photoluminescence emission spectra （PL） results clearly revealed that the recombination of photogenerated electron-hole pairs in CSCN composites was effectively inhibited due to the formation of heterojunctions. Based on the band alignments of g-C3N4 and CdS, the possible photocatalvtic mechnism was discussed.

关键词： CdS/g-C3N4 Heterojunctions Photocatalytic stability Photocatalytic mechanism

Radical and(photo)electron transfer induced mechanisms for lignin photo-and electro-catalytic depolymerization

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Green Energy & Environment 2023年第2期8卷 383-405页

作者： kejia wu Minglong Cao Qiang Zeng Xuehui Li School of Chemistry and Chemical Engineering State Key Laboratory of Pulp&Paper EngineeringSouth China University of TechnologyGuangzhou510640China

As one of the three major components of woody biomass,lignin is a kind of natural organic polymer and the only abundant natural renewable resource with aromatic *** catalysis induced depolymerization is an important and effective approach for lignin *** particular,photocatalysis and electrocatalysis show great potential in accurately activating C-O/C-C bonds,which is a critical point of selective cleavage of *** this contribution,we focus on radical and(photo)electron transfer induced reaction mechanisms of the photo(electro)catalytic depolymerization of ***,the general situation of Carbon-centered radicals and active oxygen species mediated lignin conversion has been *** the mechanisms for(photo)electron transfer mediated lignin depolymerization have been *** the end of this review,the challenges and opportunities of photo(electro)catalysis in the applications of lignin valorization have been forecasted.

关键词： Lignin Photocatalysis Electrocatalysis Depolymerization Reaction mechanism

Selective photocatalytic aerobic oxidative cleavage of lignin C–O bonds over sodium lignosulfonate modified Fe_(3)O_(4)/TiO_(2)

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Journal of Energy Chemistry 2023年第9期84卷 89-100页

作者： kejia wu Jinrong Liang Sijie Liu Yimin Huang Minglong Cao Qiang Zeng Xuehui Li School of Chemistry and Chemical Engineering State Key Laboratory of Pulp&Paper EngineeringGuangdong Provincial Key Lab of Green Chemical Product TechnologySouth China University of TechnologyGuangzhou 510640GuangdongChina

Lignocellulose shows significantly potential in sustainable conversion to high-quality fuel and valueadded chemicals with the demands for realizing the rapid cycle of carbon resources and helping to reach carbon neutrality in *** tailoring of α-O-4,β-O-4,*** in lignin has always been viewed as "death blow" for its ***,novel sodium lignosulfonate(SL) modified Fe_(3)O_(4)/TiO_(2)(SL-Fe_(3)O_(4)/TiO_(2)) spherical particles have been developed and used as catalysts for selectively photocatalytic oxidative cleavage of organosolv *** expected,80% selective conversion of lignin in C2-C4 esters has been achieved,while C-O bonds in lignin model compounds can be effectively *** than normal hydroxyl radical-mediated photocatalytic depolymerization of lignin over TiO_(2)-based materials,in this contribution,mechanism studies indicate that photogenerated holes and superoxide anion radicals are main active species,which trigger the cleavage of α/β-O-4 bond,and the isotopelabeling study confirms the crucial factor of C_β-H dehydrogenation in cleavage of β-O-4 bonds.

关键词： Lignin Photocatalytic oxidation Selective cleavage Titanium dioxide

基于Go/No-Go范式的多任务操作实验评估军校学员的反应抑制能力

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海军军医大学学报 2024年第9期45卷 1185-1189页

作者：张倩吴可嘉赵红旗范硕江楠楠杨川锐唐露露余浩海军军医大学(第二军医大学)海军特色医学中心航空生理心理训练队上海200433 国防大学政治学院心理攻防作战与训练教研室上海201602 中国人民解放军七七六〇六部队政治工作部拉萨850000

目的探索军校学员在多任务操作情境中的反应抑制能力特点。方法选择127名军校学员作为被试,采用Go/No-Go范式进行测试,通过重复测量方差分析和分布检验等方法探索模拟驾驶任务的干扰对被试Go/No-Go测试表现的影响。结果对127名被试的测... 详细信息

目的探索军校学员在多任务操作情境中的反应抑制能力特点。方法选择127名军校学员作为被试,采用Go/No-Go范式进行测试,通过重复测量方差分析和分布检验等方法探索模拟驾驶任务的干扰对被试Go/No-Go测试表现的影响。结果对127名被试的测试结果显示,在击中率和虚报率上存在干扰任务和Go试次比例的交互作用,即在没有干扰任务时60%试次比例与40%试次比例条件下被试的击中率和虚报率差异无统计学意义(均P>0.05),而在有干扰任务时60%试次比例条件下被试的击中率和虚报率大于40%试次比例条件(均P<0.01)。在击中率、虚报率和辨别力指标d’上干扰任务的主效应显著(均P<0.01),即干扰任务降低了被试的击中率和辨别力、增大了虚报率。不同被试在有无干扰任务时辨别力的变化不同,根据无干扰任务与有干扰任务时辨别力指标d’的差值的平均数加减1个标准差,可将被试分为易受干扰组23人(18.11%)、不易受干扰组20人(15.75%)和中间组84人(66.14%)。结论干扰任务增加了军校学员在多任务操作时的心理负荷,降低了其反应抑制能力,且军校学员的反应抑制能力存在个体差异。

关键词：军校学员反应抑制多任务操作 Go/No-Go范式模拟驾驶冲突监测理论资源限制理论

Determination of perchlorate and its distribution in unhusked rice in China

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Food Quality and Safety 2022年第2期6卷 252-256页

作者： Changxin Shen Lian Liu Xiaoyao Yin Fengqin Tu kejia wu Qian wu Lingfeng Peng Min Fang Yongning wu Zhiyong Gong Key Laboratory for Deep Processing of Major Grain and 0il of Ministry of Educ ation Wuhan Polytechnic UniversityWuhanChina wuhan Institute for Food and Cosmetic Control WuhanChina China National Center for Food Safety Risk Assessment NHC Key Laboratory of Food Safety Risk AssessmentFood Safety Research Unit(2019RU014)of Chinese Academy of Medical ScienceBeiingChina

Perchlorate concentrations in 387 unhusked rice samples from 15 main producing provinces/municipality in China were investigated by high-performance liquid chromatography-tanden mass *** results indicated that perchlorate displays a mean level of 17.17μg/kg in un-husked rice ***,we also found that perchlorate is mainly observed in rice husk among these collected unhusked rice samples,while less observed in rice bran and milled ***,the perchlorate levels in rice were found in the husks(73.61%),bran(10.09%),and milled rice(19.52%),*** results indicated that there is no significantly perchlorate exposure risk in edible milled rice.

关键词： Perchlorate unhusked rice distribution China

大众-宝来汽车发动机控制系统故障设置盒的设计与教学应用

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汽车实用技术 2024年第17期49卷 146-149页

作者：吴科甲陈辉淦林凤功苏春锦孙帅福建信息职业技术学院智能制造学院福建福州350003

为有效提高学校新能源汽车专业群教师、学生对汽车发动机电控系统故障检修的实践水平,文章以大众-宝来汽车为载体,师生共研设计发动机电控系统教学故障设置盒一套,以方便教师实训教学和学生技能比赛训练。该故障设置盒可以灵活设置线路... 详细信息

为有效提高学校新能源汽车专业群教师、学生对汽车发动机电控系统故障检修的实践水平,文章以大众-宝来汽车为载体,师生共研设计发动机电控系统教学故障设置盒一套,以方便教师实训教学和学生技能比赛训练。该故障设置盒可以灵活设置线路断路、短路、对调、虚接等,模拟真实故障维修过程。设计流程如下:首先依据大众-宝来电路图,梳理发动机电脑板线束;其次设计故障设置盒尺寸和针脚的排版方式;然后在电脑板上焊接线束并在线束焊接结束后检测其导通性;最后将带有故障设置盒的教学用车与原车进行功能验证,验证所设计教学用车故障设置盒的有效性。

关键词：发动机电控系统故障设置教学应用

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Level pinning of anti-PT-symmetric circuits for efficient wireless power transfer

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National Science Review 2024年第1期11卷 215-224页

作者： Zhiwei Guo Fengqing Yang Haiyan Zhang Xian wu Qiong wu kejia Zhu Jun Jiang Haitao Jiang Yaping Yang Yunhui Li Hong Chen MOE Key Laboratory of Advanced Micro-Structured Materials School of Physics Sciences and Engineering Tongji University Department of Electrical Engineering Tongji University School of Automotive Studies Tongji University

Wireless power transfer(WPT) technology based on magnetic resonance(a basic physical phenomenon)can directly transfer energy from the source to the load without wires and other physical contacts, and has been successfully applied to implantable medical devices, electric vehicles, robotic arms and other ***, due to the frequency splitting of near-field coupling, the resonant WPT system has some unique limitations, such as poor transmission stability and low efficiency. Here, we propose anti-resonance with level pinning for high-performance WPT. By introducing the anti-resonance mode into the basic WPT platform, we uncover the competition between dissipative coupling and coherent coupling to achieve novel level pinning, and construct an effective anti-parity-time(anti-PT)-symmetric non-Hermitian system that is superior to previous PT-symmetric WPT schemes. On the one hand, the eigenvalue of the anti-PT-symmetric system at resonance frequency is always pure real in both strong and weak coupling regions, and can be used to overcome the transmission efficiency decrease caused by weak coupling, as brought about by, for example, a large size ratio of the transmitter to receiver, or a long transmission *** the other hand, due to the level pinning effect of the two kinds of coupling mechanisms, the working frequency of the system is guaranteed to be locked, so frequency tracking is not required when the position and size of the receiver change. Even if the system deviates from the matching condition, an efficient WPT can be realized, thereby demonstrating the robustness of the level pinning. The experimental results show that when the size ratio of the transmitter coil to the receiver coil is 4.29(which is in the weak coupling region), the transfer efficiency of the anti-PT-symmetric system is nearly 4.3(3.2) times higher than that of the PT-symmetric system when the matching conditions are satisfied(deviated). With the miniaturization and integration of d

关键词： non-Hermitian system wireless power transfer anti-PT-symmetric circuits synthetic dimension metamaterials

Theta Oscillations Support Prefrontal-hippocampal Interactions in Sequential Working Memory

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Neuroscience Bulletin 2024年第2期40卷 147-156页

作者： Minghong Su kejia Hu Wei Liu Yunhao wu Tao Wang Chunyan Cao Bomin Sun Shikun Zhan Zheng Ye Institute of Psychology Chinese Academy of SciencesBeijing 100101China Department of Psychology University of Chinese Academy of SciencesBeijing 100049China Department of Neurosurgery Center for Functional NeurosurgeryRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Institute of Neuroscience Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China

The prefrontal cortex and hippocampus may support sequential working memory beyond episodic memory and spatial *** stereoelectroencephalography(SEEG)study investigated how the dorsolateral prefrontal cortex(DLPFC)interacts with the hippocampus in the online processing of sequential *** patients with epilepsy(eight women,age 27.6±8.2 years)completed a line ordering task with SEEG recordings over the DLPFC and the *** showed longer thinking times and more recall errors when asked to arrange random lines clockwise(random trials)than to maintain ordered lines(ordered trials)before recalling the orientation of a particular ***,the ordering-related increase in thinking time and recall error was associated with a transient theta power increase in the hippocampus and a sustained theta power increase in the DLPFC(3–10 Hz).In particular,the hippocampal theta power increase correlated with the memory precision of line ***,theta phase coherences between the DLPFC and hippocampus were enhanced for ordering,especially for more precisely memorized ***,the theta band DLPFC→hippocampus influence was selectively enhanced for ordering,especially for more precisely memorized *** study suggests that theta oscillations may support DLPFC-hippocampal interactions in the online processing of sequential information.

关键词： Sequential working memory Hippocampus Dorsolateral prefrontal cortex Theta oscillations Stereoelectroencephalography(SEEG) Phase coherence Granger causality

散粒介质剪切带细观力学结构几何演化与稳定性分析

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岩石力学与工程学报 2018年第A01期37卷 3686-3700页

作者：刘洋李爽吴可嘉北京科技大学土木系北京100083

基于离散单元法对剪切带宏细观力学行为进行数值模拟,将通过网格剖分形成的loop单元作为细观力学的基本结构单元,对剪切带内、外不同类型loop单元的数量、几何形态、受力特征与抗滑稳定性的演化进行细致分析,讨论其发展变化与试样强度... 详细信息

基于离散单元法对剪切带宏细观力学行为进行数值模拟,将通过网格剖分形成的loop单元作为细观力学的基本结构单元,对剪切带内、外不同类型loop单元的数量、几何形态、受力特征与抗滑稳定性的演化进行细致分析,讨论其发展变化与试样强度、剪胀发展之间的内在联系。模拟结果表明,剪切过程中剪切带内、外loop结构的数量和几何形态发展规律基本一致但强弱不同;其受力特征及抗滑稳定性在剪切带内、外产生了明显的差异。剪切过程中高阶loop单元比例增加且变得更扁平,低阶loop单元比例减少而形状基本保持不变。宏观尺度上的剪胀在细观力学结构演化上表现为低阶单元结构向高阶单元结构的转化,反映了试样在特定受力与边界条件下形成的自组织结构。提出2类滑动率的概念用于分析loop结构的抗滑稳定性,剪切带内、外滑动率在峰值后的发展趋势明显不同,最大滑动比例点与应力–应变关系曲线峰值应力点的相对位置也不同。剪切过程中高阶loop单元形成的强力链在力学层面上承担与传递了相对较大的外荷载,且抗滑稳定性较高;低阶loop单元抗滑稳定性差,其向高阶loop单元转化过程中发生的接触滑动与颗粒重组,是散体材料塑性变形发展的主要原因。

关键词：数值模拟散粒介质剪切带细观结构剪胀离散元法