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Conserved and differentiated functions of CIK receptor kinases in modulating stem cell signaling in Arabidopsis

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Molecular Plant 2021年第7期14卷 1119-1134页

作者： Yafen zhu Chong Hu Yanwei Cui Li Zeng Sunjingnan Li Mingsong zhu Fanhui meng Shuting Huang Li long Jing Yi Jia Li Xiaoping Gou Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations School of Life SciencesLanzhou UniversityLanzhou 730000China

The shoot apical meristem(SAM)and root apical meristem(RAM)act as pools of stem cells that give rise to aboveground and underground tissues and organs in higher plants,*** CLAVATA3(CLV3)-WUSCHEL(WUS)negative-feedback loop acts as a core pathway controlling SAM homeostasis,while CLV3/EMBRYO SURROUNDING REGION(ESR)40(CLE40)and WUSCHEL-RELATED HOMEOBOX5(WOX5),homologs of CLV3 and WUS,direct columella stem cell ***,CLV3 INSENSITIVE KINASES(CIKs)have been shown to be essential for maintaining SAM homeostasis,whereas whether they regulate the distal root meristem remains to be ***,we report that CIKs are indispensable for transducing the CLE40 signal to maintain homeostasis of the distal root *** found that the cik mutant roots displayed disrupted quiescent center and delayed columella stem cell(CSC)*** assays demonstrated that CIKs interact with ARABIDOPSIS CRINKLY4(ACR4)in a ligand-independent manner and can be phosphorylated by ACR4 in *** addition,the phosphorylation of CIKs can be rapidly induced by CLE40,which partially depends on *** CIKs act as conserved and redundant regulators in the SAM and RAM,our results demonstrated that they exhibit differentiated functions in these meristems.

关键词： ACR4 CIKs CLE40 stem cells distal root meristem phosphorylation

Mesoporous zeolites as efficient catalysts for oil refining and natural gas conversion

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Frontiers of Chemical Science and Engineering 2013年第2期7卷 233-248页

作者： Jie zhu Xiangju meng Fengshou XIAO Department of Chemistry Zhejiang University Hangzhou 310028China College of Biological Chemical Sciences and Engineering Jiaxing University Jiaxing 314001 China

Zeolites have been regarded as one of the most important catalysts in petrochemical industry due to their excellent catalytic performance. However, the sole micro- pores in zeolites severely limit their applications in oil refining and natural gas conversion. To solve the problem, mesoporous zeolites have been prepared by introducing mesopores into the zeolite crystals in recent years, and thus have the advantages of both mesostructured materials （fast diffusion and accessible for bulky molecules） and micro- porous zeolite crystals （strong acidity and high hydro- thermal stability）. In this review, after giving a brief introduction to preparation, structure, and characterization of mesoporous zeolites, we systematically summarize catalytic applications of these mesoporous zeolites as efficient catalysts in oil refining and natural gas conversion including catalytic cracking of heavy oil, alkylation, isomerization, hydrogenation, hydrodesulfurization, methane dehydroaromatization, methanol dehydration to dimethyl ether, methanol to olefins, and methanol to hydrocarbons.

关键词： mesoporous zeolite catalysis oil refining,natural gas conversion

Analyzing Land-use Change in Farming-pastoral Transitional Region Using Autologistic Model and Household Survey Approach

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Chinese Geographical Science 2013年第6期23卷 716-728页

作者： zhu Likai meng Jijun MAO Xiyan Department of Geography University of Florida Laboratory for Earth Surface Processes School of Urban and Environmental SciencesPeking University

Land change science （LCS） strives to understand and model land-use change, which will further advance the understanding of multiple issues in the socio-ecological systems. Based on GIS/RS techniques, autologistic model, and household survey method, this study investigated major land use changes and their causes from 1978 to 2008 in Uxin Banner （county-level）, Inner Mongolia in China and then developed an understanding of the relationships between household livelihood and land-use pattern. Results showed that cultivated land increased from 1988 to 2000, and leveled offafter 2000. Built-up land increased stably for the period 1978 2008. The change of grassland and bare land differed among the three periods. From 1978 to 1988, grassland increased by 23.3%, and bare land decreased by 20.48%. From 1988 to 2000, bare land expanded by 1.7%, but grassland declined by 1.3%. From 2000 to 2008, an increase in grassland area by 1.8% was observed, but a decrease in bare land area by 9.0% was witnessed. The autologistic models performed better than logistic models as indicated by lower Akaike Information Criterion （AIC） values. Factors associated with human activities significantly correlated with the change of cultivated land, forest land, grassland, and built-up land. The produce prices and extensive cultivated land use are major issues in the farming area. This study suggests that completing land circulation systems and maintaining the stability of price are effective solutions. By contrast, reclamation and overgrazing are major concerns in the pastoral areas. Implementing environmental policies effectively, transferring population out of rural pastoral areas, and developing modem animal husbandry are effective ways to address these issues.

关键词： farming-pastoral transitional region land use change driving force livelihood autologistic model Uxin Banner(county-level) Inner Mongolia

Coupled Aerodynamic and Hydrodynamic Analysis of Floating Offshore Wind Turbine Using CFD Method

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第1期33卷 80-87页

作者： Wu Jun meng long Zhao Yongsheng He Yanping State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240P.R.China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Shanghai 200240P.R.China School of Naval Architecture Ocean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240P.R.China

To simulate floating offshore wind turbine(FOWT)in coupled wind-wave domain via CFD method,the NREL 5MW wind turbine supported by the OC3-Hywind Spar platform is modeled in the STAR-CCM+ *** on the Reynolds-averaged Navier-Stokes(RANS)equations and re-normalisation group(RNG)k-εturbulence model,the rotor aerodynamic simulation for wind turbine is *** results agree well with the NREL *** advantage with the volume of fluid(VOF)method and dynamic fluid body interaction(DFBI)technology,the dynamic responses of the floating system with mooring lines are simulated under the coupled wind-wave sea *** free-decay tests for rigid-body degrees of freedom(DOFs)in still water and hydrodynamic tests in a regular wave are performed to validate the numerical model by comparing its result with the results simulated by ***,the simulations of the overall FOWT system in the coupled wind-wave flow field are carried *** relationship between the power output and dynamic motion responses of the platform is *** numerical results show that the dynamic response of wind turbine performance and platform motions all vary in the same frequency as the inlet *** platform motion,the power output of wind turbine is more sensitive than the thrust *** study may provide some reference for further research in the coupled aero-hydro simulation of FOWT.

关键词： floating offshore wind turbine(FOWT) computational fluid dynamics(CFD) aerodynamic perform ance dynamic fluid body interaction

Experimental investigation on dynamic mechanical characteristics and microstructure of steam-cured concrete

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Science China(Technological Sciences) 2014年第10期57卷 1902-1908页

作者： long GuangCheng WANG meng XIE YouJun MA KunLin School of Civil Engineering Central South University National Laboratory for High Speed Railway Construction Technology

Steam-cured concrete is widely used to manufacture prefabricated units of high-speed railway foundation structure such as girder and track *** dynamic mechanical property of steam-cured concrete is one of the key properties affecting service performance of high-speed railway foundation *** the present paper,serial macro/micro-experiments were carried out to investigate the dynamic elastic modulus,shear modulus,damping ratio,and microstructure of steam-cured *** relationships between compositions,curing regime,microstructure,and dynamic properties of steam-cured concrete as well as the corresponding mechanisms were *** results indicate that steam-cured concrete in early age has a larger dynamic elastic modulus and shear modulus as well as a smaller damping ratio compared with standard-cured *** the contrary,at a later age a slightly smaller dynamic elastic modulus and a larger damping ratio of steam-cured concrete are *** of mineral admixture results in a bit lower dynamic elastic modulus and damping ratio of concrete than that of the control specimen without mineral *** achievements can provide some fundamental suggestions for materials parameters selection during structural design of steam-cured concrete precast element.

关键词： steam-cured concrete dynamic elastic modulus shear modulus damping ratio microstructure

Novel technology of electroless Ni-W-P on plastics and its interface behavior

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中国有色金属学会会刊：英文版 2004年第z1期14卷 136-139页

作者： WANG Tian-xu HU Yong-jun meng Ji-long College of Mechanical Engineering South China University of TechnologyGuangzhou 510641 China College of Mechanical Engineering South China University of TechnologyGuangzhou 510641 China College of Mechanical Engineering South China University of TechnologyGuangzhou 510641 China

The electroless Ni-W-P coatings on polyoxymethylene(POM) were prepared. The POM was pretreated by hot spraying Al powder on it. Before the electroless Ni-W-P deposition, the POM with Al coating was flash plated in alkaline bath. The mechanism of Ni-W-P deposition was studied and the technology was optimized. The XRD analysis shows that the "as-deposited" Ni-W-P plating has mixed crystalline structure. The hardness value of deposits is more than HV700. The abrasion resistance of deposits is six times more than that of POM. Bending test was used to determine the cohesion between the deposits and the substrates. SEM was used to study the behavior of surface abrasion and interface bonding condition. The reason for the excellent cohesion was interpreted.

关键词： plastics electroless plating interface Ni alloy

Deliberate design of MOF-based pre-catalyst rationalizing the structural reconstruction toward efficient oxygen evolution reaction

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Science China Chemistry 2025年

作者： Yunhui Chen meng Tian Zhongqi Zhang Guangzhao Wang Yan Guo Jing Wu Dawei Qi Zhenhua Yan Xiangyu Liu Xi Liu State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia University Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology of Chongqing School of Electronic Information Engineering Yangtze Normal University Frontiers Science Center for New Organic Matter Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) State Key Laboratory of Advanced Chemical Power Sources College of Chemistry Nankai University School of Chemistry and Chemical Engineering In-situ Center for Physical Sciences Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University

Metal-organic frameworks （MOFs）,that have emerged as promising electrocatalysts in oxygen evolution reaction （OER）,usually undergo structural reconstruction to form metal hydroxides as active ***,it remains a great challenge to design and synthesize ideal MOF-based pre-catalysts for properly cognizing and utilizing the reconstruction process toward efficient OER ***,the well-defined MOF-808 is post-modified by 2-hydroxyphosphonoacetic acid （HPAA） to form a micro-adsorber that enables to capture of metal ions ***3+and Ni2+ions are synergistically anchored into the microadsorber,developing a Fe/Ni-containing pre-catalyst that can be dynamically electrooxidized to be an active and stable dual-site electrocatalyst denoted by R-MOF-HPAA@FeNi with abundant metal *** a result,R-MOF-HPAA@FeNi exhibits an excellent OER performance with a low overpotential of 272 mV and Tafel slope of 35.9 m V dec-1,as well as long-term stability over 300 h at 10 m A *** and theoretical calculations suggest the resulting catalyst mainly follows a lattice oxygen mechanism （LOM） of dual-metal-site mechanism （DMSM）.Owing to the chelating role of HPAA,the post-synthesized MOF-HPAA behaves as a trap to uniformly and firmly adhere Fe3+and Ni2+ions,leading to a functionalized MOF-based pre-catalyst which can be structurally evolved into atomic level-distributed OER electrocatalysts.

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A New System to Evaluate Comprehensive Performance of Hard-Rock Tunnel Boring Machine Cutterheads

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Chinese Journal of Mechanical Engineering 2019年第6期32卷 72-84页

作者： Ye zhu Wei Sun Junzhou Huo Zhichao meng School of Mechanical and Engineering Dalian Jiaotong UniversityDalin 116000China School of Mechanical and Engineering Dalian University of TechnologyDalian 116000China

The accurate performance evaluation of a cutterhead is essential to improving cutterhead structure design and predicting project cost. Through extensive research, this paper evaluates the performance of a tunnel boring machine(TBM) cutterhead for cutting ability and slagging ability. This paper propose cutting efficiency, stability, and continuity of slagging as the evaluation indexes of comprehensive cutterhead performance. On the basis of research of true TBM engineering applications, this paper proposes a calculation method for each index. A slagging efficiency index with a ratio of the maximum di erence between the slagging amount and average slagging is established. And a slagging stability index with a ratio of the maximum slagging fluctuation and average slagging is presented. Meanwhile, a cutting efficiency index by the weighed average value of multistage rock fragmentation of a cutter’s specific energy is established. The Robbins and China Railway Construction Corporation(CRCC) cutterheads are evaluated. The results show that under the same thrust and torque, the slagging stability of the CRCC scheme is worse, but the slagging continuity of the CRCC scheme is better. The cutting ability index shows that the CRCC cutterhead is more efficient.

关键词： Evaluation of cutterhead Cutting ability Slagging ability Rock fragmentation load

PAM: an efficient power-aware multilevel cache policy to reduce energy consumption of storage systems

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Frontiers of Computer Science 2019年第4期13卷 850-863页

作者： Xiaodong meng Chentao WU Minyi GUO long ZHENG Jingyu ZHANG Shanghai Key Laboratory of Scalable Computing and Systems Department of Computer Science & Engineering Shanghai Jiao Tong University Shanghai 200240 China

Energy consumption is one of the most significant aspects of large-scale storage systems where multilevel caches are widely used. In a typical hierarchical storage structure, upper-level storage serves as a cache for the lower level, forming a distributed multilevel cache system. In the past two decades, several classic LRU-based multilevel cache policies have been proposed to improve the overall I/O performance of storage systems. However, few power-aware multilevel cache policies focus on the storage devices in the bottom level, which consume more than 27% of the energy of the whole system [1]. To address this problem, we propose a novel power-aware multilevel cache (PAM) policy that can reduce the energy consumption of high-performance and I/O bandwidth storage devices. In our PAM policy, an appropriate number of cold dirty blocks in the upper level cache are identified and selected to flush directly to the storage devices, providing high probability extension of the lifetime of disks in standby mode. To demonstrate the effectiveness of our proposed policy, we conduct several simulations with real-world traces. Compared to existing popular cache schemes such as PA? LRU, PB-LRU, and Demote, PAM reduces power consumption by up to 15% under different I/O workloads, and improves energy efficiency by up to 50.5%.

关键词： storage system multilevel cache energy consumption I/O performance hint