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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 661-672页

作者： Dan Zhang Jiabin hu jun Cheng Zheng-Guang Wu huaicheng Yan IEEE Zhejiang University of Technology Guangxi Normal University Zhejiang University the East China University of Science and Technology

This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic ***,a fixed-time disturbance observer(FTDO) is designed to deal with the adverse effects of model uncertainties and external disturbances in the manipulator *** an adaptive scheme is used and the adaptive FTDO(AFTDO) is developed,so that the priori knowledge of the lumped disturbance is not ***,a new non-singular fast terminal sliding mode(NFTSM) surface is designed by using an arctan function,which helps to overcome the singularity problem and enhance the robustness of the *** on the estimation of the lumped disturbance by the AFTDO,a fixed-time non-singular fast terminal sliding mode controller(FTNFTSMC)is developed to guarantee the trajectory tracking errors converge to zero within a fixed *** settling time is independent of the initial state of the *** addition,the stability of the AFTDO and FTNFTSMC is strictly proved by using Lyapunov ***,the fixed-time NFESM(FTNFTSM) algorithm is validated on a 2-link manipulator and comparisons with other existing sliding mode controllers(SMCs) are *** comparative results confirm that the FTNFTSMC has superior control performance.

关键词： Disturbance observer(DO) fixed-time non-singular sliding mode control robotic manipulator trajectory tracking

Energy Harvesting in the Wake of An Inverted C-Shaped Bluff Body

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China Ocean Engineering 2024年第1期38卷 68-80页

作者： WANG jun-lei LI Shen-fang Md.Mahbub ALAM Zhu Hong-jun hu Guo-biao School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450000China Center for Turbulence Control Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China Internet of Things Thrust The Hong Kong University of Science and Technology(Guangzhou)Guangzhou 511400China

This paper proposes a novel wake-induced vibration(WIV)-based energy harvesting system consisting of two bluff *** inverted C-shaped bluff body is stationary installed at the upstream position to generate an interference wake street,and a cylinder bluff body equipped with a transducer is elastically suspended at the downstream position to harness WIV *** hydrodynamics and energy harvesting(EH)performance of the proposed system are investigated via experimental *** reduced velocity(U*)ranging from 2 to 14(the corresponding Reynolds number ranging from 15100 to 106200)is considered in the present *** is found that the wake generated by the inverted C-shaped bluff body significantly affects the EH *** the opening angle(α)of the C-shaped bluff body increases the vibration amplitude of the downstream cylinder,thereby increasing the harvested *** the spacing(L)between two bluff bodies is two times the cylinder diameter(D),the wake-induced vibration(WIV)mode is observed,while the combined WIV and wake galloping(WG)mode occurs whenαis 150°,and L equals 3D or *** average drag coefficient becomes negative when L is 2D,3D,or *** carefully configuring a C-shaped bluff body,the wake generated by it can bring an augmenting effect on the vibration of the downstream EH *** example,the RMS power output of the proposed EH system reaches a maximum of 0.31 W at U*=8 and L=4D,which is 300%greater than that of its traditional ***,after a number of case stud-ies,it is identified that the proposed EH system can achieve the best performance whenαis 150°and L=2D.

关键词： wake-induced vibration vortex-induced vibration galloping energy harvesting bluff body

A quantum chemistry study on reaction mechanisms of SO_2 with O_3 and H_2O_2

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浙江大学学报（英文版）A辑：应用物理与工程 2009年第9期10卷 1327-1333页

作者： Shu-dong JIANG Zhi-hua WANG jun-hu zhou Zheng-cheng WEN Ke-fa CEN State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

反应机制那么有 O 3 和 H 22> O 2 用量化学 ab initio 方法被调查。所有反应物，产品，和转变状态的结构在 B3LYP/6-311G+(3df,2p ) 水平被优化，并且精力计算在 G2M 水平被做。那么有 O 3 和 H 22 反应 > O 2 由 O 抽象和哦抽象发生... 详细信息

反应机制那么有 O 3 和 H 22> O 2 用量化学 ab initio 方法被调查。所有反应物，产品，和转变状态的结构在 B3LYP/6-311G+(3df,2p ) 水平被优化，并且精力计算在 G2M 水平被做。那么有 O 3 和 H 22 反应 > O 2 由 O 抽象和哦抽象发生了由那么2,分别地，最后那么形成3+O2( 3Σ g −)和 H 2那么4。为那么 2+O3 反应障碍高度被预言是有 3.61 × 1 的一个率常数的 9.68 kcal/mol 在 300 K 的 0 −23 厘米 3/(molecule · s) ，它在试验性的上面的限制下面。率常数为这预言反应与那在 250 ∼500 K 为标准和技术(NIST ) 由国家研究所提供了一致很好。为那么 2+H2 O 2 反应障碍高度被预言是有 2.48 × 1 的一个率常数的 62.39 kcal/mol 在 300 K 的 0 −61 厘米 3/(molecule · s) 。

关键词：二氧化硫反应机制过氧化氢量子化学化学研究臭氧从头计算方法速率常数

Large Eddy Simulation of Vertical Structure and Size Density of Deep Layer Clouds

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Advances in Atmospheric Sciences 2024年第8期41卷 1629-1642,1668-1670页

作者： Bangjun CAO Xianyu YANG jun WEN Qin hu Ziyuan Zhu School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China Institute for Geophysics and Meteorology University of CologneCologne 50923Germany

In a convective scheme featuring a discretized cloud size density, the assumed lateral mixing rate is inversely proportional to the exponential coefficient of plume size. This follows a typical assumption of-1, but it has unveiled inherent uncertainties, especially for deep layer clouds. Addressing this knowledge gap, we conducted comprehensive large eddy simulations and comparative analyses focused on terrestrial regions. Our investigation revealed that cloud formation adheres to the tenets of Bernoulli trials, illustrating power-law scaling that remains consistent regardless of the inherent deep layer cloud attributes existing between cloud size and the number of clouds. This scaling paradigm encompasses liquid, ice, and mixed phases in deep layer clouds. The exponent characterizing the interplay between cloud scale and number in the deep layer cloud, specifically for liquid, ice, or mixed-phase clouds, resembles that of shallow convection,but converges closely to zero. This convergence signifies a propensity for diminished cloud numbers and sizes within deep layer clouds. Notably, the infusion of abundant moisture and the release of latent heat by condensation within the lower atmospheric strata make substantial contributions. However, this role in ice phase formation is limited. The emergence of liquid and ice phases in deep layer clouds is facilitated by the latent heat and influenced by the wind shear inherent in the middle levels. These interrelationships hold potential applications in formulating parameterizations and post-processing model outcomes.

关键词： deep layer cloud cloud spatial structure cloud size density large eddy simulation

Plant regeneration in the new era:from molecular mechanisms to biotechnology applications

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Science China(Life Sciences) 2024年第7期67卷 1338-1367页

作者： Chunli Chen Yuxin hu Momoko Ikeuchi Yuling Jiao Kalika Prasad Ying hua Su jun Xiao Lin Xu Weibing Yang Zhong Zhao Wenkun zhou Yun zhou Jian Gao Jia-Wei Wang National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhan 430070China College of Life Science and Technology Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Plant Molecular Physiology Institute of BotanyChinese Academy of Sciences(CAS)China National Botanical GardenBeijing 100093China Division of Biological Sciences Graduate School of Science and TechnologyNara Institute of Science and TechnologyNara 630-0192Japan State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Center for Quantitative BiologyAcademy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China Indian Institute of Science Education and Research Pune 411008IndiaThiruvananthapuram 695551India State Key Laboratory of Wheat Improvement College of Life SciencesShandong Agricultural UniversityTai’an 271018China Sino-German Joint Research Center on Agricultural Biology Shandong Agricultural UniversityTai’an 271018China Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology(IGDB)CASBeijing 100101China CAS-JIC Centre of Excellence for Plant and Microbial Science(CEPAMS) IGDBCASBeijing 100101China National Key Laboratory of Plant Molecular Genetics CEMPSInstitute of Plant Physiology and Ecology(SIPPE)CASShanghai 200032China CEPAMS SIPPECASShanghai 200032China Hefei National Laboratory for Physical Sciences at the Microscale CEMPSSchool of Life SciencesDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230027China State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100193China Department of Botany and Plant Pathology and Center for Plant Biology Purdue UniversityWest Lafayette 47907USA School of Life Science and Technology Shang

Plants or tissues can be regenerated through various *** animal regeneration,cell totipotency and pluripotency are the molecular basis of plant *** systematic studies on Arabidopsis thaliana gradually unravel the fundamental mechanisms and principles underlying plant ***,plant hormones,cell division,epigenetic remodeling,and transcription factors play crucial roles in reprogramming somatic cells and reestablishing meristematic *** research on basal non-vascular plants and monocot crops has revealed that plant regeneration differs among species,with various plant species using distinct mechanisms and displaying significant differences in regenerative *** multi-omics studies at the single-cell level,tracking plant regeneration processes in real-time,and deciphering the natural variation in regenerative capacity will ultimately help understand the essence of plant regeneration,improve crop regeneration efficiency,and contribute to future crop design.

关键词： apical meristem model species regeneration phytohormone plant cell reprogramming somatic embryogenesis

Factors and Their Impact on Treatment Effect of Acupuncture in Different Outcomes:A Meta-Regression of Acupuncture Randomized Controlled Trials

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Chinese Journal of Integrative Medicine 2024年第3期30卷 260-266页

作者： XIU Wen-cui GANG Wei-juan zhou Qi SHI Lan-jun hu Xiang-yu MING Tian-yu LUO Zhen ZHANG Yu-qing JING Xiang-hong Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing100700China China Center for Evidence-Based Traditional Chinese Medicine China Academy of Chinese Medical SciencesBeijing100700China Department of Health Research Methods Evidenceand ImpactMcMaster UniversityHamiltonOntarioL8S 4L8Canada Center for Evidence-Based Integrative Medicine-Clarity Collaboration Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China

Background:The effects of acupuncture have varied in different randomized controlled trials(RCTs),and there are many factors that influence treatment effect of acupuncture in different outcomes,with conflicting ***:To identify factors and their impact on the treatment effect of acupuncture in different ***:Acupuncture RCTs were searched from 7 databases including Medline(Pub Med),Embase,Cochrane Central Register of Controlled Trials,China National Knowledge Infrastructure,Wanfang Database,VIP Database,and China Biology Medicine disc between January 1st,2015 and December 31st,*** studies must compare acupuncture to no acupuncture,sham acupuncture,or waiting lists,and report at least 1patient-important outcome.A multi-level meta-regression was conducted using a 3-level robust mixed model and univariate analyses were performed for all independent variables,even those excluded from the multivariable model due to *** used thresholds of 0.2 and 0.4 for the difference of standardized mean differences(SMDs),categorising them as small(0.4) ***:The pain construct analysis involved 211 effect estimates from 153 studies and 14 independent ***-frequency acupuncture treatment sessions produced larger effects compared to low-frequency sessions [large magnitude,the difference of adjusted SMDs 0.46,95% confidence interval(CI) 0.07 to 0.84;P=0.02].The non-pain symptoms construct analysis comprised 323 effect estimates from 231 studies and 15 independent *** acupuncture showed moderately larger effects when compared to non-penetrating acupuncture(0.30,95% CI 0.06 to 0.53;P=0.01).The function construct analysis included 495 effect estimates from 274 studies and 14 independent *** acupuncture and the flexible acupuncture regimen showed moderately larger effects,compared to non-penetrating acupuncture and fixed regimen,respectively(0.40,95% CI 0

关键词： acupuncture randomized controlled trial patient-important outcome meta-regression

Iterative physical optics method based on efficient occlusion judgment with bounding volume hierarchy technology

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Journal of Electronic Science and Technology 2024年第1期22卷 1-12页

作者： Yang Su Yu-Mao Wu jun hu Key Laboratory for Information Science of Electromagnetic Waves(MoE) School of Information Science and TechnologyFudan UniversityShanghai200433China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This paper builds a binary tree for the target based on the bounding volume hierarchy technology,thereby achieving strict acceleration of the shadow judgment process and reducing the computational complexity from the original O(N^(3))to O(N^(2)logN).Numerical results show that the proposed method is more efficient than the traditional *** is verified in multiple examples that the proposed method can complete the convergence of the ***,the proposed method avoids the error of judging the lit-shadow relationship based on the normal vector,which is beneficial to current iteration and *** with the brute force method,the current method can improve the simulation efficiency by 2 orders of *** proposed method is more suitable for scattering problems in electrically large cavities and complex scenarios.

关键词： Bounding volume hierarchy Cavity scattering Iterative physical optics(IPO)

The Effect of Blending Ratio on the Structure and Properties of the PPR/PS In situ Fiber Reinforced System Prepared by Multi-Flow Vibration Injection Molding

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Chinese Journal of Polymer Science 2024年第6期42卷 851-863页

作者： Yan-Jiang Li Meng-Long hu jun-Wen Zhang Qiang Fu Jie Zhang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

To enhance the mechanical properties of polypropylene random copolymer(PPR),polystyrene(PS)with four different contents were added to the PPR matrix through melt ***,using the Multi-Flow Vibration Injection Molding(MFVIM)technology,PPR/PS in situ microfiber composites(MFC)with different blending ratios were *** results indicated that blending ratio had a great impact on the phase morphology and crystal structure of MFVIM samples,which was different from those of conventional injection molding(CIM)*** ultrafine fibers could be formed under the shear field and could absorb the PPR molecular chains to form hybrid shish-kebab ***,the PPR matrix could also form shish-kebab structures under the effect of strong *** the PS content reached 20%,under the combined action of PS in situ microfibers and highly oriented crystal structure,the tensile strength and Young’s modulus of the sample were obviously improved and the impact strength remained at a relatively high *** a strong and tough balanced PPR based material was *** results provide valuable insights for expanding the industrial and daily-life applications of PPR and show promising development prospects.

关键词： PPR MFVIM In situ microfibers Shearfield Hybrid shish-kebab structures

Improving slurryability, rheology,and stability of slurry fuel from blending petroleum coke with lignite

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Petroleum Science 2015年第1期12卷 157-169页

作者： jun-Hong Wu Jian-Zhong Liu Yu-Jie Yu Rui-Kun Wang jun-hu zhou Ke-Fa Cen State Key Laboratory of Clean Energy Utilization Zhejiang University

Petroleum coke and lignite are two important fossil fuels that have not been widely used in China. Petroleum coke-lignite slurry （PCLS）, a mixture of petro- leum coke, lignite, water, and additives, efficiently utilizes the two materials. In this study, we investigate the effects of the proportion （7） of petroleum coke on slurryability, rheo- logical behavior, stability, and increasing temperature characteristics of PCLSs. The results show that the fixed- viscosity solid concentration （COo） increases with increasing 7. The ~Oo of lignite-water slurry （LWS, ~ = 0） is 46.7 %, compared to 71.3 % for the petroleum coke-water slurry （PCWS, c~ --- i00 %）, while that of PCLS is in between the two values. The rheological behavior of PCLS perfectly fits the power-law model. The PCWS acts as a dilatant fluid. As decreases, the slurry behaves first as an approximate Newtonian fluid, and then turns into a pseudo-plastic fluid that exhibits shear-thinning behavior. With increasing ct, the rigid sedimentation and water separation ratio （WSR） increase, indicating a decrease in the stability of PCLS. When α is 60-70 %, the result is a high-quality slurry fuel for industrial applications, which has high slurryability （ω0 = 57-60 %）, good stability （WSR 〈 2 %）, and superior pseudo-plastic behavior （n = 0.9）.

关键词： Petroleum coke Lignite Coal-water slurry Rheological characteristics Slurry stability

High-entropy oxide-supported platinum nanoparticles for efficient hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1537-1546页

作者： Ming-Yu Fan Jia-jun Wang jun Zhao Hong Zhang Tian-Yi Ma Xiao-Peng Han Wen-Bin hu School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Key Laboratory of Advanced Ceramics and Machining TechnologyTianjin UniversityTianjin300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou350207China School of Science RMIT UniversityMelbourneVIC3000Australia

High-entropy oxides(HEOs)are a new class of single-phase structures with unique electronic and catalytic properties;therefore,it is worthwhile to explore their applications in *** this study,a Pt/(FeCoNiCrAl)_(3)O_(4)nanohybrid using HEO as a support was developed as an efficient catalyst for the hydrogen evolution reaction(HER).Pt/(FeCoNiCrAl)_(3)O_(4)exhibited high HER activity with a low overpotential of 22 mV at10 mA·cm^(-2),outperforming other binary,ternary,and quaternary *** HER activity of Pt/(FeCoNiCrAl)_(3)O_(4)was higher than that of a commercial Pt/C with a significantly lower Pt *** catalyst exhibited good activity and long-term stability(60 h)in an electrolytic water-splitting *** good activity can be attributed to the fact that the introduction of Pt effectively facilitates electronic interactions between Pt and the *** addition,the HEO substrate was more favorable for dispersing Pt particles,optimizing the electrochemical specific surface area,and significantly reducing the charge resistance of the *** study extends the application of HEOs in electrocatalysis and demonstrates the promising prospects of HEOs as supports for electrocatalysts.

关键词： High-entropy oxides Hydrogen evolution reaction Nanohybrid Water electrolysis