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Green Energy & Environment 2022年第3期7卷 525-532页

作者： Yu wang kun Zhou Environmental Process Modelling Centre Nanyang Environment and Water Research InstituteNanyang Technological University1 CleanTech Loop637141Singapore School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang Avenue639798Singapore

Two-dimensional(2D) materials have exhibited great potential for replacing costly Pt for oxygen reduction reaction(ORR) because of their distinctive structural features and high pre-site activity.However,their performance is generally hindered by the limited density of active sites(e.g.,at the layer edges).Although they feature a high exposure of surface sites,these sites are typically inert for ORR.Herein,through density functional theory calculations,we propose a promising ORR catalyst candidate,a 2D TaTe_(2) nanosheet,which has an intrinsic high basal-plane activity.Both of the thermodynamic and kinetic processes are explored,which demonstrates that the basal-plane Te sites of the TaTe_(2) nanosheet have great potential for facilitating ORR.Specifically,we construct a microkinetic model of ORR proceeding on TaTe_(2),which unveils its dynamic intermediate coverage under different electrode potentials and identifies the dominating associative pathway.The theoretical half-wave potential of TaTe_(2) is predicted to be 0.87 V,which exceeds those of the well-established Pt(111) and Fe–N–C single-atom catalysts computed at the same level.This study not only presents the first 2D,non-Pt ORR catalyst candidate with an intrinsic basal-plane activity but also offers a rational methodology for unveiling the mechanism/activity of ORR and other electrochemical reactions.

关键词： plane intrinsic kinetic

Changes in diversity,composition and assembly processes of soil microbial communities during Robinia pseudoacacia L.restoration on the Loess Plateau,China

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Journal of Arid Land 2022年第5期14卷 561-575页

作者： Wang Kun wang Xiaoxia FEI Hongyan WAN Chuanyu HAN Fengpeng State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau College of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712100China Research Center on Soil&Water Conservation Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China

Robinia pseudoacacia L.(RP)restoration has increased vegetation cover in semi-arid regions on the Loess Plateau of China,but ecological problems have also occurred due to RP restoration,such as reduced soil moisture.Further,it is still uncertain how microbial diversity,composition and assembly processes change with RP restoration in semi-arid regions.Therefore,amplicon sequencing of small subunit ribosomal ribonucleic acid(16S rRNA)and internal transcribed spacer(ITS)genes was performed to study soil bacterial and fungal diversity,composition and assembly processes at four study sites with different stand ages of RP plantations(Y10,RP plantation with stand ages less than 10 a;Y15,RP plantation with stand ages approximately 15 a;Y25,RP plantation with stand ages approximately 25 a;and Y40,RP plantation with stand ages approximately 40 a)along a 40-a chronosequence on the Loess Plateau.The diversity of soil bacteria and fungi increased significantly during the restoration period from 10 to 15 a(P<0.05).However,compared with Y15,bacterial diversity was lower at Y25 and Y40,and fungal diversity remained stable during the restoration period between 25 and 40 a.The relative abundances of Proteobacteria and Ascomycota increased during the restoration period from 10 to 15 a.Conversely,after 15 a of restoration,they both decreased,whereas the relative abundances of Actinomycetes,Acidobacteria and Basidiomycota gradually increased.The variations in soil bacterial communities were mainly related to changes in soil total nitrogen,nitrate nitrogen and moisture contents,while soil fungal communities were mainly shaped by soil organic carbon and nitrate nitrogen contents.Bacterial communities were structured by the heterogeneous selection and stochastic process,while fungal communities were structured primarily by the stochastic process.The RP restoration induced an increase in the relative importance of heterogeneous selection on bacterial communities.Overall,this study reveals the changes in microbial diversity,community comp

关键词： Robinia pseudoacacia microbial diversity community structure community assembly restoration semi-arid regions

Impact of Mandatory Provisions on the Validity of Juristic Acts: A Path for Legal Policy Analysis

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Contemporary Social Sciences 2023年第6期8卷 1-19页

作者： Wang Kun Lingnan Normal University

Contrary to the approach in judicial practice,Paragraph 1,Article 153,of the Civil Code of the People’s Republic of China,as a rule of invalidity for violating mandatory provisions,does not adopt a dichotomy towards mandatory provisions with effectiveness and administrative characteristics,yet it maintains the legislative philosophy of differentiation.It leaves unspecified whether mandatory provisions that do not explicitly render a juristic act invalid impact the act’s validity,entrusting this determination to the discretion of judges on a case-by-case basis.When judges,under the authority of Paragraph 1,Article 153 of the Civil Code,explore the normative intent of mandatory provisions to assess their effect on the validity of juristic acts,they should engage in legal policy analysis centered on consequence-based argumentation to overcome the limitations of norm typological analysis.This analysis employs a reasoning model predicated on the normative purpose,utilizing a consequencefocused interpretative approach for formulating and arguing propositions of rules applicable to pending cases,thereby arriving at case-specific conclusions.Since the invalidation of juristic acts serves as an auxiliary regulatory tool for the state economy and society,a consequence-oriented interpretation needs to be based on the idea of mutual instrumentalization of public and private laws.This entails predicting the outcomes of negating the validity of a juristic act in industrial regulatory scenarios and assessing these outcomes within the framework of public and private regulatory instruments.

关键词： rule of invalidity for violating mandatory provisions juristic acts legal policy analysis consequencebased argumentation regulation

Direct and Indirect Electro-Oxidative Intramolecular C–H Aminations

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Transactions of Tianjin University 2022年第6期28卷 469-481页

作者： Huiqiao wang kun Xu School of Chemical and Environmental Engineering Anyang Institute of TechnologyAnyang 455099China Faculty of Environment and Life Beijing University of TechnologyBeijing 100124China

The ubiquity of N-heterocycles in marketed drugs makes the development of metal-free methodologies for constructing C–N bonds of considerable importance.As an environmentally friendly method,electro-oxidative intramolecular C–H amination has emerged as a powerful platform for synthesizing nitrogen-containing heterocycles under metal-and external oxidant-free conditions.In this minireview,the main achievements in this direction since 2020 are summarized,with an emphasis on the substrate scope and mechanistic aspects.The reactions are classifi ed into two categories:direct and indirect electro-oxidative intramolecular C–H aminations.

关键词： Electrosynthesis C–H amination N-heterocycle Indirect electrolysis

高校辅导员职业能力提升路径探析——基于王正坤工作室建设的探索与实践

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教育教学论坛 2020年第34期 251-252页

作者：王正坤山东青年政治学院政治与公共管理学院党总支山东济南250103

如何探索有效提升辅导员职业能力的新路径成了高校思政工作迫切需要解决的突出问题。以山东青年政治学院王正坤工作室为例,探索了依托辅导员工作室提升辅导员职业能力的路径。

关键词：辅导员辅导员工作室职业能力提升

The intrinsic strength prediction by machine learning for refractory high entropy alloys

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钨科技(英文) 2023年第4期5卷 531-538页

作者： Yong-Gang Yan kun wang Kazuo Inamori School of Engineering Alfred UniversityAlfredNY14802USA

Herein,we trained machine learning(ML)model to quickly and accurately conduct the strength prediction of refractory high entropy alloys(RHEAs)matrix.Gradient Boosting(GB)regression model shows an outstanding performance against other ML models.In addition,the heat of fusion and atomic size difference is shown to be paramount to the strength of the high entropy alloys(HEAs)matrix.In addition,we discussed the contribution of each feature to the solid solution strengthening(SSS)of HE As.The excellent predictive accuracy shows that the GB model can be efficient and reliable for the design of RHEAs with desired strength.

关键词： Refractory high entropy alloys Solid solution strengthening Machine learning Lattice distortion Heat of fusion

Mitigating quantum errors via truncated Neumann series

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Science China(Information Sciences) 2023年第8期66卷 92-102页

作者： kun wang Yu-Ao CHEN Xin wang Institute for Quantum Computing Baidu Research

Quantum gates and measurements on quantum hardware are inevitably subject to hardware imperfections that lead to quantum errors. Mitigating such unavoidable errors is crucial to explore the power of quantum hardware better. In this paper, we propose a unified framework that can mitigate quantum gate and measurement errors in computing quantum expectation values utilizing the truncated Neumann series.The essential idea is to cancel the effect of quantum error by approximating its inverse via linearly combining quantum errors of different orders produced by sequential applications of the quantum devices with carefully chosen coefficients. Remarkably, the estimation error decays exponentially in the truncated order, and the incurred error mitigation overhead is independent of the system size, as long as the noise resistance of the quantum device is moderate. We numerically test this framework for different quantum errors and find that the computation accuracy is substantially improved. Our framework possesses several vital advantages: it mitigates quantum gate and measurement errors in a unified manner, it neither assumes any error structure nor requires the tomography procedure to completely characterize the quantum errors, and most importantly,it is scalable. These advantages empower our quantum error mitigation framework to be efficient and practical and extend the ability of near-term quantum devices to deliver quantum applications.

关键词： near-term quantum devices quantum error mitigation quantum computing

Patient-derived xenograft model in colorectal cancer basic and translational research

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Animal Models and Experimental Medicine 2023年第1期6卷 26-40页

作者： Xiaofeng Liu Zechang Xin kun wang Hepatopancreatobiliary Surgery Department Ⅰ Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing)Peking University Cancer Hospital and InstituteBeijingChina

Colorectal cancer(CRC)is one of the most popular malignancies globally,with 930000 deaths in 2020.The evaluation of CRC-related pathogenesis and the discovery of po-tential therapeutic targets will be meaningful and helpful for improving CRC treat-ment.With huge efforts made in past decades,the systematic treatment regimens have been applied to improve the prognosis of CRC patients.However,the sensitivity of CRC to chemotherapy and targeted therapy is different from person to person,which is an important cause of treatment failure.The emergence of patient-derived xenograft(PDX)models shows great potential to alleviate the straits.PDX models possess similar genetic and pathological characteristics as the features of primary tu-mors.Moreover,PDX has the ability to mimic the tumor microenvironment of the original tumor.Thus,the PDX model is an important tool to screen precise drugs for individualized treatment,seek predictive biomarkers for prognosis supervision,and evaluate the unknown mechanism in basic research.This paper reviews the recent advances in constructed methods and applications of the CRC PDX model,aiming to provide new knowledge for CRC basic research and therapeutics.

关键词： colorectal cancer drug discovery patient-derived xenograft model precision medicine tumor microenvironment

Adaptive Backstepping Sliding Mode Control of Uncertain Semi-Strict Nonlinear Systems and Application to Permanent Magnet Synchronous Motor

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Journal of Systems Science & Complexity 2021年第2期34卷 552-571页

作者： wang Fang wang Jian-mei Wang Kun ZONG Qun HUA Changchun School of Science Yanshan UniversityQinhuangdao 066004China School of Electrical and Information Engineering Tianjin UniversityTianjin 300072China School of Electrical and Engineering Yanshan UniversityQinhuangdao 066004China

A disturbance observer(DOB)based-backstepping sliding mode control scheme is discussed for a class of semi-strict nonlinear system with unknown parameters and mismatched uncertainty.Firstly,adaptive technique and DOB are respectively applied to tackle the unknown parameters and mismatched uncertainty,where the DOB can effectively alleviate the chattering problem of sliding mode control(SMC).Then,exponential sliding mode surface is proposed to improve the convergence rate of the sliding mode state.The‘explosion of complexity’problem inherent in conventional backstepping control is overcome by designing the novel first-order filter.The stability of the closed-loop system is analyzed in the framework of Lyapunov stability theory,in which the tracking error converges to an arbitrarily small neighborhood around zero(ASNZ).At last,two examples are given to illustrate the effectiveness of the proposed control strategy.

关键词： Adaptive law DOB filter semi-strict nonlinear system SMC

Numerical and Experimental Study on Heat Transfer Characteristics of Single Vibrating Blade in a Channel Flow

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Journal of Thermal Science 2023年第3期32卷 982-992页

作者： HU Jinqi MIN Chunhua YANG Xuguang Wang Kun XIE Liyao School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300401China Hebei Key Laboratory of Thermal Science and Energy Clean Utilization Hebei University of TechnologyTianjin 300401China

The heat transfer characteristics of the vibrating blades of different shapes were numerically modeled in the present work.A single blade was arranged in a channel with vertical or horizontal alignment.Both the static environment and the channel flow were considered.Four types of blades,rectangular,trapezoidal,serrated,and folding,were comparably modeled.The results showed that the vibrating blade could effectively enhance the convection heat transfer of the heated surface with a smaller increase of pressure drop.For the static environment,the heat transfer performance of the vertical alignment of the blade is better than the horizontal alignment.For channel flow,the opposite conclusion is obtained.For the inlet velocity of channel flow v_(inlet)=2 m/s and v_(inlet)=6m/s,the maximum improvement of the local convection heat transfer coefficient is about 98%and 12%,respectively.The corresponding pressure drops were reduced and increased by 9.5%and 8.8%,respectively.The vibrating blade can effectively improve the convection heat transfer at lower inlet velocity.Under the same working conditions,the pressure drop difference between the four shapes of fan blades is less than 1%,and the folding blade has the best local heat dissipation performance.

关键词： convection heat transfer vibrating blade alignment of the blade shape of the blade