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On the new results of global attractive set and positive invariant set of the Lorenz chaotic system and the applications to chaos control and synchronization

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Science in china(Series F) 2005年第3期48卷 304-321页

作者： LIAO Xiaoxin 1, 2. 3 , fu Yuli 4 & XIE Shengli 4 1. Department of Control Science & Control Engineering, Huazhong University of Science & Technology, wuhan 430074,{2. 2. {2. of Automation, wuhan University of Science & Technology, wuhan 430070,{2. 3. {2. of Information, Central South University of Economy, Politics and law, wuhan 430064,{2. 4. {2. of Electronics & Information Engineering, South{2. University of Technology, Guangzhou 510640,{2. Correspondence should be addressed to Liao Xiaoxin (email: xiaoxin_liao@***) 1. Department of Control Science & Control Engineering Huazhong University of Science & Technology 430074 Wuhan China 2. {1. of Automation Wuhan University of Science & Technology 430070 Wuhan China 3. school of Information Central South University of Economy Politics and Law 430064 Wuhan China 4. school of Electronics & Information Engineering South China University of Technology 510640 Guangzhou China

Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control {1.s are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.

关键词： Lorenz chaotic system global attractive set positive invariant set globally exponential tracking globally exponential synchronization.

Refractive index changes induced by sheet beams with various intensity distributions in LiNbO_(3):Fe crystal

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 399-412页

作者： ZHANG Peng1. ZHAO Jianlin1. xu Honglai1. SUN Yidong{1. YANG Dexing1.& WANG Meirong1.1. Institute of Optical Information Science and Technology, school of Science, Northwestern Polytechnical University, Xi’an 71.07{1. china {1. school of Science, Xi’an Jiaotong University, Xi’an 71.049, china 1. Institute of Optical Information Science and Technology School of Science Northwestern Polytechnical University 710072 Xi’an China 2. {1. of Science Xi’an Jiaotong University 710049 Xi’an China

According to the Kukhtarev equations and a simplified model based on the photovoltaic charge carriers transport mechanism, the distributions of the index changes (DICs) in LiNbO3:Fe crystals induced by sheet beams with various intensity profiles are theoretically analyzed. The numerically simulated results coincide with the analytic expressions deduced from the simplified model. The DICs in a LiNbO3:Fe crystal induced by sheet beams with rectangular, Gaussian and square law profiles are measured by using the interferometric method. By employing the analytic expressions, the experimental data points are well fitted. By utilizing the angular spectrum theory and the ray equation, the uniformities of the intensity profiles of the writing beams along the propagation directions and the influences of the self-defocusing effect of the crystal are numerically simulated, respectively. The results show that the experimental results are reliable. The numerically simulated method and the analytic expressions can be both employed to predict the DICs induced by sheet beams with various light intensity profiles. {1.rthermore, utilizing writing beams with proper intensity profiles, any desired index distributions could be obtained.

关键词： LiNbO3:Fe crystal, light intensity profile, distribution of refractive index changes, sheet beam.

Study on the isothermal oxidation behavior in air of Ti_(3)AlC_(2. sintered by hot pressing

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Science china(Technological Sciences) 2006年第5期49卷 513-520页

作者： xu xuewen1. 2. LI Yangxian1. MEI Bingchu2. ZHU Jiaoqun2. LIU Heyan1.& QU Jingping1.1. school of Material Science and Engineering, Hebei University of Technology, Tianjin 3001.0, china 2. State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, {2. Univer- sity of Technology, {2. 430070, china 1. school of Material Science and Engineering Hebei University of Technology Tianjin 300130 China 2. State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

The isothermal oxidation behavior at 900–1.00°C for 2. h in air of bulk Ti3AlC2.with 2.8 wt% TiC sintered by means of hot pressing was investigated in the work. The isothermal oxidation behavior generally followed a... 详细信息

The isothermal oxidation behavior at 900–1300°C for 2. h in air of bulk Ti3AlC2.with 2.8 wt% TiC sintered by means of hot pressing was investigated in the work. The isothermal oxidation behavior generally followed a parabolic rate law. The parabolic rate constants increased from 1.39×10[10] kg[2.·m[4]·s[1] at 900°C to 5.56×10[9] kg[2.·m[4]·s[1] at 1300°C. The calculated activation energy was 136.45 kJ/mol. It was demonstrated that Ti3AlC2.had excellent oxidation resistance due to the continuous, dense; adhesive protect scales consisted of a mass of α-Al2.3; a little of TiO2./or Al2.iO5. In principle, the oxide scale was grown by the inward diffusion of O[2.; the outward diffusion of Ti[4+]; Al[3+]. The rapid outward diffusion of cations usually resulted in the formation of cracks, gaps,; holes.

关键词： Ti3AlC2. oxidation behavior, kinetics.

Pre-MASLD:Should it be defined separately?

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 1-3页

作者： Hang-Kai Huang You-Ming Li Cheng-fu {1. Department of Gastroenterology Zhejiang Provincial Clinical Research Center for Digestive Diseasesthe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic liver diseases,yet it has not received sufficient attention[1..Over the past two decades,the overall global prevalence of NAFLD has risen from 2.%to 37%[2..The disease burden of NAFLD is fueled by the epidemic of obesity and diabetes[3].It is estimated that more than half of patients with diabetes have NAFLD.

关键词： NAFLD liver diseases

Metallic Sb-stabilized porous silicon with stable SEI and high electron/ion conductivity boosting lithium-ion storage performance

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Rare Metals 2024年第9期43卷 4234-4242页

作者： Jia-Guo Deng Hao-Qin Feng Yu-Long xu Si-Guang Guo Jian-Ping Li Kai-{1. Huo Ji-Jiang {1. Biao Gao Pual-K.Chu The State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University of Science and TechnologyWuhan 430081China wuhan National Laboratory for Optoelectronics(WNLO) School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan 430074China Department of Physics Department of Materials Science&Engineeringand Department of Biomedical EngineeringCity University of Hong KongHong Kong 999077China

Silicon(Si)has mild discharge potential and high theoretical capacity,making it a highly desirable material for lithium-ion batteries(LIBs).Nevertheless,the excessive volume expansion,poor ion/electron conductiv ity and unstable solid electrolyte interface(SEI)hinde practical application to ***,the metallic antimony(Sb)stabilized porous Si(SiDSb)composite was prepared by magnesiothermic reduction of Sb_(2.O_(3)and Mg_(2.Si and chemical etching to remove the by-product of *** highly conductive Sb nanodots embedded in the Si liga ments promote not only the formation of conductive and stable LiF-rich SEI,but also the electron/ion transpor ability of *** to the outstanding bulk/interface stability,excellent conductivity,as well as ideal porous structure,the SiDSb electrode demonstrates a capacity of82. mAh·g^(-1.after undergoing 32. turns at 1.00 mA·g^(-1..Additionally,it exhibits a stable capacity of 675 m Ah·g^(-1.when tested at a higher current density of 5000 m A·g^(-1..The results reveal a viable solution to solve three problems at the same time,namely the poor conductivity,inferior SEI and excessive volume expansion of Si,boding well for the design of Si-based materials for high-energy LIBs.

关键词： Silicon Anodes Lithium-ion batteries Antimony Solid electrolyte interphase

Sporopollen analysis of Core B1. in the southern Yellow Sea and the reflected characteristics of climate changes

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Chinese Science Bulletin 2003年第B06期48卷 42-48页

作者： fu Mingzuo~(1.{1.3), LI Zhen~1. xu Xiaowei~1.& SHl xuefa~1.1. Key Laboratory of Marine Sedimentology and Environmental Geology, First institute of Oceanography. State Oceanic Administration, Qingdao {1.6061. china {1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao {1.6071. china 3. Graduate {2., Chinese Academy of Sciences, Beijing 1.0039. china 1. Key Laboratory of Marine Sedimentology and Environmental Geology First institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. Institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate school Chinese Academy of Sciences 100039 Beijing China

Eight sporopollen zones have been divided based on the results of high-resolution sporopollen analysis of Core B1. in the southern Yellow Sea. Based on the results along with ^1.C datings and the subbottom profiling data,climatic and environmental changes since the last stage of late Pleistocene are discussed. The main conclusions are drawn as follows: (1. the vegetation evolved in the process of coniferous forest-grassland containing broad-leaved trees→coniferous and broad-leaved mixed forest→coniferons and broad-leaved mixed forest-grassland prevailed by coniferous trees→coniferous and broad-leaved mixed forest-grassland containing evergreen broad-leaved trees→coniferons and broad-leaved mixed forest-grassland prevailed by broadleaved trees→deciduous broad-leaved forest-meadow containing evergreen broad-leaved trees→coniferous and broadleaved mixed forest-grassland prevailed by broad-leaved trees→coniferous and broad-leaved mixed forest containing evergreen broad-leaved trees; (2. eight stages of climate changes are identified as the cold and dry stage, the temperate and wet stage, the cold and dry stage, the warm and dry stage, the temperate and wet stage, the hot and dry stage, the temperate and dry stage, then the warm and dry stage in turn; (3) the sedimentary environment developed from land,to littoral zone, to land again, then to shore-neritic zone; and (4) the Yellow Sea Warm Current formed during early-Holocene rather than Atlantic stage.

关键词：中国黄海气候变化碳1.年代测定底基压型数据更新世沉积环境大西洋

Designing silver niobate-based relaxor antiferroelectrics for ultrahigh energy storage performance

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Journal of Advanced Ceramics 2024年第8期13卷 1282-1290页

作者： Zhengdong Hu Zhen Liu Bing Han Haonan Peng Kai Da Zequan xu Zhengqian {1. Zhigao Hu Genshui Wang Key Laboratory of Inorganic functional Materials and Devices Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China school of Physics and Electronic Science East China Normal UniversityShanghai 200241China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

AgNbO_(3)(AN)and modified AgNbO_(3) have been extensively investigated as promising lead-free antiferroelectric(AFE)energy storage *** studies have focused mainly on the use of an ion dopant at the A/B site to obtain a stabilized AFE phase;however,simultaneous improvements in the recoverable energy storage density(Wrec)and efficiency(n)are stll difficult to ***,we innovatively constructed a AgNbO_(3)-NaNbO_(3)-(Sr_(0.7)Bi_(0.2.)TiO_(3)(AN-NN-SBT)ternary solid solution to achieve a relaxor AFE in AgNbO_(3)-based *** coexistence of antiferroelectric(M3)and paraelectric(O)phases in 0.8(0.7AgNbO_(3)-0.3NaNbO_(3))-0.2.Sro.7Bio.2.TiO_(3) confirms the successful realization of a relaxor AFE,attributed to multiple ion occupation at the A/B ***,a high Wrec of 7.53 ***^(-3) and n of 74.0% are acquired,together with superior stability against various temperatures,frequencies,and cycling ***,a high power density(2.8.7 MW·cm^(-3))and fast discharge speed(41.4 ns)are also demonstrated for the AgNbO_(3)-based relaxor *** work presents a promising energy storage AgNbO_(3)-based ternary solid solution and proposes a novel strategy for AgNbO_(3)-based energy storage via the design of relaxor AFE materials.

关键词： AgNbO_(3)(AN)-based ceramics relaxor antiferroelectric(RAFE) paraelectric(PE) energy storage performance

Development of MoS_(2.-stainless steel catalyst by 3D printing for efficient destruction of organics via peroxymonosulfate activation

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Journal of Environmental Sciences 2024年第1期135卷 108-117页

作者： Yufeng Liu Jianhui xu Xin {1. Pengxu Wang Dan Li Yunfei Zhang Shenggui Chen Chunhui Zhang Peng Liu school of Environment and Civil Engineering Dongguan University of TechnologyDongguan 523808China school of Art and Design Guangzhou Panyu PolytechnicGuangzhou 511483China Dongguan Institute of Science and Technology Innovation Dongguan University of TechnologyDongguan 523808China school of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China

Herein,a novel MoS_(2.-stainless steel composite material was first synthetized via a 3D printing method(3DP MoS_(2.-SS)for peroxymonosulfate(PMS)activation and organics *** with MoS_(2.-SS powder/PMS system(0.37 g/(m^(2./min)),4.3-fold higher k_(FLO)/S_(BET)value was obtained in 3DP MoS_(2.-SS/PMS system(1.60 g/(m^(2./min),resulting from the superior utilization of active *** observed that 3DP MoS_(2.-SS significantly outperformed the 3DP SS due to the enhanced electron transfer rate and increased active ***,Mo^(4+)facilitated the Fe^(2.)/Fe^(3+)cycle,resulting in the rapid degradation of florfenicol(FLO).Quenching experiments and electron paramagnetic resonance spectra indicated that·OH,SO_(4)·^(-),O_(2.·^(-)and^(1.O_(2.were involved in the degradation of *** effect of influencing factors on the degradation of FLO were evaluated,and the optimized degradation efficiency of 98.69%was achieved at 1.mM PMS and pH of *** degradation products were detected by UPLC/MS analyses and several possible degradation pathways were proposed to be the cleavage of C-N bonds,dechlorination,hydrolysis,defluorination and *** addition,3DP MoS_(2.-SS/PMS system also demonstrated superior degradation performance for 2.chlorophenol,acetaminophen,ibuprofen and *** study provided deep insights into the MoS_(2.-SS catalyst prepared by 3DP technology for PMS activation and FLO-polluted water treatment.

关键词： 3D printing Stainless steel MoS_(2. Peroxymonosulfate activation Degradation mechanism

{1012.twin–twin intersection-induced lattice rotation and dynamic recrystallization in Mg–6Al–3Sn–2.n alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1529-1539页

作者： Bin-Jiang Lv Sen Wang fu-Hao Gao Ning Cui Yi-Nan Li Tie-Wei {1. Feng Guo school of Mechanical and Automotive Engineering Qingdao University of Technology266520China Key Lab of industrial Fluid Energy Conservation and Pollution Control Qingdao University of Technology266520China

This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2.n alloy during different strain rates of an isothermal *** results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012.tension twins,and 60°1010>boundaries formed due to twin–twin intersections under different strain *** twin variants with 60°1010>boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°1010>boundaries transformed into new grains via dynamic recrystallization.

关键词： Mg alloy Twin-twin intersection Lattice rotation Dynamic recrystallization