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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization

Strong Current-State Opacity Verification of Discrete-Event Systems Modeled With Time Labeled Petri Nets

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 54-68页

作者： Tao Qin Li yin Gaiyun liu Naiqi Wu Zhiwu Li the Institute of Systems Engineering Macau University of Science and Technology IEEE the School of Electro-Mechanical Engineering Xidian University

This paper addresses the verification of strong currentstate opacity with respect to real-time observations generated from a discrete-event system that is modeled with time labeled Petri nets. The standard current-state opacity cannot completely characterize higher-level security. To ensure the higher-level security requirements of a time-dependent system, we propose a strong version of opacity known as strong current-state opacity. For any path(state-event sequence with time information)π derived from a real-time observation that ends at a secret state, the strong current-state opacity of the real-time observation signifies that there is a non-secret path with the same real-time observation as π. We propose general and non-secret state class graphs, which characterize the general and non-secret states of time-dependent systems, respectively. To capture the observable behavior of non-secret states, a non-secret observer is ***, we develop a structure called a real-time concurrent verifier to verify the strong current-state opacity of time labeled Petri nets. This approach is efficient since the real-time concurrent verifier can be constructed by solving a certain number of linear programming problems.

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Tribological properties of oil-impregnated polyimide in double-contact friction under micro-oil lubrication conditions

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Friction 2023年第8期11卷 1493-1504页

作者： Jinbang LI Jinyang liu kai LI Ningning ZHOU Yang liu Xudong HU Shunli yin Guorong WANG School of Mechanical Engineering&Mechanics Ningbo UniversityNingbo 315211China Healthy&Intelligent Kitchen Engineering Research Center of Zhejiang Province Ningbo 315211China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China Key Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo 315211China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

Oil-impregnated porous polyimide(iPPI)materials are usually used as retainer for *** these bearings,balls and rings,balls and retainers are two different kinds of *** this paper,the friction and wear properties of iPPI were investigated using steel(disc)–steel(ball)–iPPI(pin)double-contact friction test rig for simulating the actual contact in *** results show that compared with that of iPPI–steel single contact,the friction coefficient of iPPI–steel in double contacts is lower and decreases with the amount of additional *** surface of iPPI in single contact suffers more wear compared with that in double *** from single contact,the worn surfaces of iPPI in double contacts are *** Raman spectra of worn surfaces of balls and discs indicate thatα-Fe_(2)O_(3) and Fe_(3)O_(4) were formed during rubbing of the double *** nanoscale iron oxide particles are found on the worn surfaces of iPPI in double contacts;on the contrary,few particles could be found on the surface in single *** double-contact friction,the nanoscale wear debris penetrates inside the iPPI material through the process of extruding and recycling of oil,which is the mechanism of the blackening of the iPPI worn *** studies show that the double-contact friction method is a new and effective method to study the friction in bearings,especially for those with polymer retainer.

关键词： porous polyimide(PPI) oil-impregnated material double-contact friction micro-oil lubrication

间歇与持续训练对体力活动不足成人生活质量影响的Meta分析

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中国组织工程研究 2025年第8期29卷 1727-1740页

作者：郑华坤殷明越刘骞四川农业大学体育学院四川省雅安市625014 上海体育大学竞技运动学院上海市200438

目的:高强度间歇训练(high-intensity interval training,HIIT)和中等强度持续训练(moderate-intensity continuous training,MICT)对临床慢性病患者生活质量均有改善作用,但其对于体力活动不足成人的应用效果与调节因素尚不明确。文章... 详细信息

目的:高强度间歇训练(high-intensity interval training,HIIT)和中等强度持续训练(moderate-intensity continuous training,MICT)对临床慢性病患者生活质量均有改善作用,但其对于体力活动不足成人的应用效果与调节因素尚不明确。文章旨在探究HIIT与MICT对体力活动不足成人生活质量的应用效果与调节因素。方法:在Web of Science核心合集、Medline(EBSCO Host)、PubMed和Cochrane Library数据库中进行文献检索,检索时限为各数据库建库至2023年9月。纳入文献类型为随机对照试验,研究对象为体力活动不足成人。采用RevMan 5.4软件和GRADE证据评价框架对纳入文献进行质量评价。使用R Studio(版本4.2.0)进行随机效应模型的主效应合并。亚组分析、回归分析和敏感性分析用于探讨研究异质性来源和调节因素。结果:①纳入32项中等至高质量的随机对照试验,共2083名体力活动不足成人对象(HIIT组474例;MICT组708例;对照组901例)。②相比于无训练对照组,HIIT(Hedges’g=0.61;95%CI:0.40-0.83;I2=45%)与MICT(Hedges’g=0.66;95%CI:0.25-1.08;I2=89%)均能显著提升生活质量。当直接比较HIIT与MICT时,二者之间的影响未观察到显著差异(Hedges’g=-0.01;95%CI:-0.23-0.21;I2=0%)。③亚组分析结果显示,HIIT和MICT在提高身体层面的生活质量更为有效(HIIT:Hedges’g=0.82 vs.0.75;MICT:Hedges’g=0.74 vs.0.55),而骑行在提高整体生活质量方面有更好的趋势(HIIT:Hedges’g=0.74 vs.0.36;MICT:Hedges’g=1.08 vs.0.52)。④回归分析未识别出任何显著的调节因素(所有因素P>0.05)。⑤上述Meta分析均未发现发表偏倚(Egger检验P>0.05)。结论:①中高级别的证据表明,HIIT与MICT均能改善体力活动不足成人的生活质量,且二者之间的干预效果类似。因此,在选择这两种方案时,需综合考虑安排灵活性、时间经济性以及应用可行性等因素制订个性化运动方案。②文章推荐在应用HIIT时,3次/周,使用低量方案(例如,每次5组,每组1 min),以80%-95%最大心率进行骑行可达理论最佳改善效果。③尽管MICT可提高生活质量,但尚无充分证据显示增加运动时长会带来额外益处。因此,建议在实施MICT时,每周进行3次以上,每次训练时长控制在25-60 min,并以50%-75%最大心率进行骑行,以达到理论上预期的最佳改善效果。

关键词：运动干预高强度间歇训练中等强度持续训练生活质量 Meta分析体力活动不足身心健康随机对照试验

Leakage of an eagle flight feather and its influence on the aerodynamics

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Chinese Physics B 2021年第3期30卷 335-345页

作者： Di Tang Dawei liu yin Yang Yang Li Xipeng Huang kai liu College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China High Speed Aerodynamic Institute China Aerodynamics Research and Development CenterMianyang 621000China Chengdu State-Owned Jinjiang Machine Factory Chendu 610043China

We investigate how the barb of bird feathers is changed along both the rachis and *** investigate the microstructures and the mechanical behaviors of barbs,a series of barbs are manually cut from an eagle’s primary feather to observe the cross sections.Aλ-like cross section with a tiny hook is observed at the right feet at each ***,a measurement of the setup system is developed to evaluate the leakage ratio of a feather followed by a numerical predicting approach based on the CFD *** is found that the air leakage increases linearly against the pressure,and the predicted results coincide well with the experimental ***,the influences of leakage of the flight feather on both steady and unsteady aerodynamics are studied.

关键词： biomaterial feather leakage large prey microstructure barbules cross-section aerodynamics

State Feedback Sliding Mode Control without Chattering by Constructing Hurwitz Matrix for AUV Movement

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International Journal of Automation and computing 2011年第2期8卷 262-268页

作者： Huan-yin Zhou kai-Zhou liu Xi-Sheng Feng State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 PRC School of Electric East China Institute of Technology Fuzhou 344000 PRC Graduate School of the Chinese Academy of Sciences Beijing 100039 RRC

This paper presents a new method to eliminate the chattering of state feedback sliding mode control （SMC） law for the mobile control of an autonomous underwater vehicle （AUV） which is nonlinear and suffers from unknown disturbances system. SMC is a well-known nonlinear system control algorithm for its anti-disturbances capability, while the chattering on switch surface is one stiff question. To dissipate the well-known chattering of SMC, the switching manifold is proposed by presetting a Hurwitz matrix which is deducted from the state feedback matrix. Meanwhile, the best switching surface is achieved by use of eigenvalues of the Hurwitz matrix. The state feedback control parameters are not only applied to control the states of AUV but also connected with coefficients of switching surface. The convergence of the proposed control law is verified by Lyapunov function and the robust character is validated by the Matlab platform of one AUV model.

关键词： Autonomous underwater vehicle (AUV) state feedback sliding mode control (SMC) switching manifold Hurwitz matrix Matlab platform Lyapunov function.

Synthesis and Crystal Structure of (CO) 5ReSnMe 2Re(CO) 5

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Chinese Journal of Structural Chemistry 1999年第2期18卷 39-43页

作者： Li, J liu, H Song, XQ kai, L yin, N Nankai Univ State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China Nankai Univ Inst Elementoorgan Chem Tianjin 300071 Peoples R China

The crystal structure of the title complex (CO) 5ReSnMe 2Re(CO) 5, (C 12 H 6O 10 Re 2Sn, M r =801.27), has been determined by single crystal X ray diffraction. The crystal is monoclinic with space group P2 1/n (NO.14), a=10.587(2), b=12.392(2), c = 14.594(3) , β = 100.59(3)°, V = 1882(1) 3, D x = 2.828 g·cm -3 , F(000)=1432, μ =14.3759mm -1 , Z =4, and final R =0 0440 and R w =0 0483 for 1954 reflections ( I≥3σ(I )). In the complex the Sn atom is connected to two methyl groups and two Re atoms which are in slightly distorted tetrahedral arrangement. The Re atom is coordinated by five carbonyl ligands and one Sn atom, forming an octahedral structure.

关键词： metal carbonyl cluster Re complex synthesis crystal structure

Interconnections between diabetic corneal neuropathy and diabetic retinopathy:diagnostic and therapeutic implications

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Neural Regeneration Research 2025年第8期20卷 2169-2180页

作者： Mingyi Yu Faith Teo En Ning Chang liu Yu-Chi liu Tissue Engineering and Stem Cell Group Singapore Eye Research InstituteSingapore Yong Loo Lin School of Medicine National University of SingaporeSingapore Department of Cornea and External Eye Disease Singapore National Eye CenterSingapore Ophthalmology and Visual Sciences Academic Clinical Program Duke-NUS Medical SchoolSingapore

Diabetic corneal neuropathy and diabetic retinopathy are ocular complications occurring in the context of diabetes *** corneal neuropathy refers to the progressive damage of corneal *** retinopathy has traditionally been considered as damage to the retinal ***,growing evidence suggests that diabetic retinopathy is a complex neurovascular disorder resulting from dysfunction of the neurovascular unit,which includes both the retinal vascular structures and neural *** retinopathy is one of the leading causes of blindness and is frequently screened for as part of diabetic ocular ***,diabetic corneal neuropathy is commonly overlooked and underdiagnosed,leading to severe ocular surface *** studies have found that these two conditions tend to occur together,and they share similarities in their pathogenesis pathways,being triggered by a status of chronic *** review aims to discuss the interconnection between diabetic corneal neuropathy and diabetic retinopathy,whether diabetic corneal neuropathy precedes diabetic retinopathy,as well as the relation between the stage of diabetic retinopathy and the severity of corneal *** also endeavor to explore the relevance of a corneal screening in diabetic eyes and the possibility of using corneal nerve measurements to monitor the progression of diabetic retinopathy.

关键词： cornea corneal nerves diabetes diabetic corneal neuropathy diabetic retinopathy retina

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天然和饱水红砂岩三轴压缩蠕变变形试验研究

三峡大学学报（自然科学版） 2025年第1期47卷 9-15页

作者：刘桃根胡凯李玲王伟湖南工学院土木与建筑工程学院湖南衡阳421002 河海大学岩土工程科学研究所南京210098 江西职业技术大学建筑工程学院江西九江332007

蠕变特性和长期强度是红砂岩地区岩体工程安全评价的关键要素,饱水软化效应对红砂岩蠕变特性和长期强度具有重要影响.采用全自动岩石三轴压缩伺服流变仪,开展天然与饱水红砂岩的三轴压缩试验和三轴压缩蠕变试验.试验结果表明:峰值强度... 详细信息

蠕变特性和长期强度是红砂岩地区岩体工程安全评价的关键要素,饱水软化效应对红砂岩蠕变特性和长期强度具有重要影响.采用全自动岩石三轴压缩伺服流变仪,开展天然与饱水红砂岩的三轴压缩试验和三轴压缩蠕变试验.试验结果表明:峰值强度、弹性模量和蠕变破坏应力因饱水软化效应而降低,围压对其降幅有削弱作用,蠕变破坏应力与峰值强度的比值在0.75~0.98之间;饱水软化效应能增强蠕变瞬时变形,减弱蠕变变形及蠕变应变速率;环向应变比轴向应变更早进入稳态蠕变阶段和加速蠕变阶段;稳态蠕变速率与偏压的变化关系符合指数函数关系;长期强度因饱水软化作用而降低,却因围压增加而增大,长期强度与峰值强度的比值在0.62~0.92之间;裂纹损伤应力与长期强度相差较大,裂纹损伤应力视为长期强度有待进一步考究.

关键词：红砂岩蠕变特性长期强度饱水软化效应裂纹损伤应力

Identification of portal vein tumor thrombus with an independent clonal origin in hepatocellular carcinoma via multi-omics data analysis

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Cancer Biology & Medicine 2019年第1期16卷 147-156页

作者： Shupeng liu Zaixin Zhou yin Jia Jie Xue Zhiyong liu kai Cheng Shuqun Cheng Shanrong liu Clinical Research Center Changhai Hospital Second Military Medical University Department of Laboratory Diagnostics Changhai Hospital Second Military Medical University Department of Hepatic Surgery VI Eastern Hepatobiliary Surgery Hospital Second Military Medical University

Objective: Multiple mechanisms underlying the development of portal vein tumor thrombus(PVTT) in hepatocellular carcinoma(HCC) have been reported recently. However, the origins of PVTT remain unknown. Increasing multi-omics data on PVTTs in HCCs have made it possible to investigate whether PVTTs originate from the corresponding primary tumors(Ts).Methods: The clonal relationship between PVTTs and their corresponding primary Ts was investigated using datasets deposited in public databases. One DNA copy number variations dataset and three gene expression datasets were downloaded for the *** analysis was performed to investigate the clonal relationship between PVTTs and Ts from an individual *** gene expression analysis was applied to investigate the gene expression profiles of PVTTs and ***: One out of 19 PVTTs had no clonal relationship with its corresponding T, whereas the others did. The PVTTs with independent clonal origin showed different gene expression and enrichment in biological processes from the primary Ts. Based on the unique gene expression profiles, a gene signature including 24 genes was used to identify pairs of PVTTs and primary Ts without any clonal relationship. Validation in three datasets showed that these types of pairs of PVTTs and Ts can be identified by the 24-gene ***: Our findings show a direct evidence for PVTT origin and consolidate the heterogeneity of PVTTs observed in *** results suggest that PVTT investigation at a molecular level is clinically necessary for diagnosis and treatment.

关键词： Hepatocellular carcinoma portal vein tumor thrombus clonal origin copy number variation bioinformatics