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A Nontrivial Product of Filtration s+5 in the Stable Homotopy of Spheres

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Acta Mathematica Sinica,English Series 2007年第3期23卷 385-392页

作者： xiu Gui liu Department of Mathematics and LPMC Nankai University Tianjin 300071 P. R. China

In this paper, some groups Ext A^s.t （Zp, Zp） with specialized s and t are first computed by the May spectrM sequence. Then we make use of the Adams spectral sequence to prove the existence of a new nontrivial family of filtration s＋5 in the stable homotopy groups of spheres πpnq＋（s＋3）pq＋（s＋1）q-5S which is represented （up to a nonzero scalar） by β＋2bohh∈ExtA^s＋5,P^nq＋（n＋3）pq＋（n＋1）q＋s（Zp, Zp） in the Adams spectral sequence, where p ≥ 5 is a prime number, n ≥3, 0≤ s 〈 p - 3, q = 2（p - 1）.

关键词： Stable homotopy of spheres Adams spectral sequence Toda Smith spectrum May spectral sequence

An Integrative Analysis of the Effects of Auxin on Jasmonic Acid Biosynthesis in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2006年第1期48卷 99-103页

作者： Jun liu xiu-Jie Wang Institute of Genetics and Development Biology the Chinese Academy of Sciences Beijing 100101 China

Auxin and jasmonic acid （JA） are two plant phytohormones that both participate in the regulation of many developmental processes. Jasmonic acid also plays important roles in plant stress response reactions. Although extensive investigations have been undertaken to study the biological functions of auxin and JA, little attention has been paid to the cross-talk between their regulated pathways. In the few available reports examining the effects of auxin on the expression of JA or JA-responsive genes, both synergetic and antagonistic results have been found. To further investigate the relationship between auxin and JA, we adopted an integrative method that combines microarray expression data with pathway information to study the behavior of the JA biosynthesis pathway under auxin treatment. Our results showed an overall downregulation of genes involved in JA biosynthesis, providing the first report of a relationship between auxin and the JA synthesis pathway in Arabidopsis seedlings.

关键词： Arabidopsis auxin biosynthesis jasmonic acid pathway.

Relative Entropy and Mean Li-Yorke Chaos Along Some Good Sequences

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Acta Mathematica Sinica,English Series 2021年第12期37卷 1947-1954页

作者： Pei WANG Er Cai CHEN xiu xiu liu Xiao Yao ZHOU Basic Teaching Department Nanjing University Jinling CollegeNanjing 210089P.R.China School of Mathematical Sciences and Institute of Mathematics Nanjing Normal UniversityNanjing 210023P.R.China

In this article,we showed that positive relative entropy implies mean Li-Yorke chaos along some good sequences in the *** result extended Li and Qiao’s result in[***.,186(2018),153-173].

关键词： Relative entropy mean Li-Yorke chaos fiber relative Pinskerσ-algebra

Scale-aware shape manipulation

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第9期15卷 764-775页

作者： Zheng liu Wei-ming WANG xiu-ping liu Li-gang liu School of Mathematical Sciences University of Science and Technology of China School of Mathematical Sciences Dalian University of Technology

A novel representation of a triangular mesh surface using a set of scale-invariant measures is *** measures consist of angles of the triangles(triangle angles) and dihedral angles along the edges(edge angles)which are scale and rigidity independent. The vertex coordinates for a mesh give its scale-invariant measures, unique up to scale, rotation, and translation. Based on the representation of mesh using scale-invariant measures, a two-step iterative deformation algorithm is proposed, which can arbitrarily edit the mesh through simple handles *** algorithm can explicitly preserve the local geometric details as much as possible in different scales even under severe editing operations including rotation, scaling, and shearing. The efficiency and robustness of the proposed algorithm are demonstrated by examples.

关键词： Differential coordinates Scale-invariant measures Surface deformation

TRANSMISSION BEHAVIOR OF MUD-PRESSURE PULSE ALONG WELL BORE

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Journal of Hydrodynamics 2007年第2期19卷 236-240页

作者： liu xiu-shan LI Bo YUE Yu-quan Petroleum Drilling Research Institute Exploration and Production Research Institute of Sinopec Corp. Dezhou 253005 China Technical Department Tianjin Branch of CNOOC Ltd. Tianjin 300452 China Jinzhou Oil Production Plant Liaohe Oilfield Branch of PetroChina Linghai 121209 China

In oil and gas industry, mud-pulse telemetry has been widely used to obtain directional data, drilling parameters, formation evaluation data and safety data, etc. Generally, the drilling mud in most current models was considered to be a single-phase fluid through which the mud pulses travel, despite the fact that the drilling mud is composed of two or more phases. In this article, a multiphase flow formula was proposed to calculate the mud-pulse velocity as mud solids and free-gas content change, and a mathematical model was put forward to simulate the dynamic-transmission behavior of the mud-pressure pulse or waves. Compared to conventional methods, the present model provides more accurate mud-pulse attenuation, and the dynamic-transmission behavior of drilling-mud pulses along well bores can also be easily examined. The model is valuable in improving the existing mud-pulse systems and developing new drilling-mud pulse systems.

关键词： measurement-while-drilling (MWD),closed-loop drilling multiphase flow numerical simulation

Relationship Among Microstructure and Properties and Heat Treatment Process of Ultra-High Strength X120 Pipeline Steel

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Journal of Iron and Steel Research International 2011年第3期18卷 59-64页

作者： ZHOU Min DU Lin-xiu liu Xiang-hua State Key Laboratory of Rolling Technology and Automation Northeastern UniversityShenyang 110004LiaoningChina

The variation of heat treatments including directed quenching and tempering off-line after controlled rolling（DQT） and quenching off-line and tempering off-line after controlled rolling（RQT） with microstructure and mechanical properties of a low-carbon microalloyed steel was compared and *** DQT,the quenched steel was obviously banded microstructure,with increasing tempering temperature,lath martensite coarsened,the cusp carbide precipitated at grain boundaries,the yield strength fluctuated slightly,and the fracture-separation was *** impact toughness was better in the steel tempered at 500 ℃ for 1 *** RQT,with increasing tempering temperature,lath martensite degenerated,intragranular and intergranular finer precipitations with smaller than 30 nm precipitated and grew up and were distributed dispersedly,the stripe-like carbides were distributed at grain boundaries,and the yield strength and tensile strengthen decreased *** impact toughness of RQT process was much better than that of DQT process,and the comprehensive mechanical properties were better for the steel tempered at 500 ℃ for 1 h of RQT process.

关键词： X120 pipeline steel heat treatment microstructure mechanical property fracture-separation

Preparation of Boron-coated Expandable Graphite and Its Application in Flame Retardant Rigid Polyurethane Foam

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Chemical Research in Chinese Universities 2015年第2期31卷 315-320页

作者： XU Dongmei liu xiu FENG Jie HAO Jianwei National Laboratory of Flame Retardant Materials School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 P. R. China Beijing Institute of Aerospace Testing Technology Beijing 100074 P R. China

A novel boron-coated expandable graphite（BEG） material was prepared by first wrapping polyvinyl alco- hoI（PVA） onto expandable graphite（EG） and then condensing with boric acid. The obtained BEG was characterized by scanning electron microscopy（SEM）, Fourier transform infrared（FT1R） spectroscopy, X-ray photoelectron spec- troscopy（XPS）, and tbermogravimetric analysis（TGA）. The fire performance and mechanical properties of the rigid polyurethane foam（RPUF） filled with BEG were investigated by limiting oxygen index（LOl）, horizontal and vertical burning, cone calorimetry（CONE）, and electronic tensile tests. BEG shows an improved compactness of the char layers upon thermal expansion, which is effective for the flame retardancy of RPUF. With a loading of 10%, RPUF/BEG exhibited a higher LOI, 〉10% reduction in heat release rate and carbon monoxide release, as well as a decrease in smoke release during the beginning of combustion compared to RPUF/EG. Moreover, the compressive strength and modulus of RPUF/BEG were increased. The improved flame retardancy of BEG on RPUF can be attributed to the suppression of the ＂popcorn effect＂ of EG by PVA-boric acid, and the improved mechanical property can be attributed to the presence of PVA.

关键词： Expandable graphite Polyvinyl alcohol Boric acid Rigid polyurethane foam Flame retardancy

L-Proline as an efficient and reusable promoter for the synthesis of coumarins in ionic liquid

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第12期9卷 990-995页

作者： xiu-hong liu Ji-cai FAN Yang liu Zhi-cai SHANG Department of Chemistry Zhejiang University Hangzhou 310027 China

The effect of L-proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF4 was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing L-proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the L-proline-[emim]BF4 system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses.

关键词： L-Proline Ionic liquid Coumarins Knoevenagel condensation

Design and analysis of electrothermal metasurfaces

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Frontiers in Energy 2023年第1期17卷 134-140页

作者： xiu liu Zhuo LI Zexiao WANG Hyeong Seok YUN Sheng SHEN Department of Mechanical Engineering Carnegie Mellon UniversityPittsburghPA 15213USA

Electrothermal metasurfaces have garneredconsiderable attention owing to their ability to dynamicallycontrol thermal infrared radiation. Although previousstudies were mainly focused on metasurfaces with infiniteunit cells, in practice, the finite-size effect can be a criticaldesign factor for developing thermal metasurfaces withfast response and broad temperature uniformity. Here, westudy the thermal metasurfaces consisting of goldnanorods with a finite array size, which can achieve aresonance close to that of the infinite case with onlyseveral periods. More importantly, such a small footprintdue to the finite array size yields response time down to ananosecond level. Furthermore, the number of the unitcells in the direction perpendicular to the axis of nanorodsis found to be insensitive to the resonance and responsetime;thus, providing a tunable aspect ratio that can boostthe temperature uniformity in the sub-Kelvin level.

关键词： modulated thermal infrared radiation metasurface nanosecond response time sub-Kelvin temperature uniformity finite size aspect ratio