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Science China Earth Sciences 2017年第10期60卷 1817-1825页

作者： TAO RenBiao ZHANG LiFei Vincenzo STAGNO CHU Xu liu xi The Key Laboratory of Orogenic Belt and Crustal Evolution School of Earth and Space SciencesPeking University Earth Sciences Department Sapienza University of Rome Department of Geology and Geophysics Yale University

The more oxidized mantle peridotites above subducting slabs than stable continental areas have been attributed to the infiltration of some oxidizing fluids released from the subducting slabs. However, knowledge for the redox states of the slabs itself is very limited. Until now, few oxybarometers can be directly used to constrain the redox states of the subducting *** rutile-ilmenite oxybarometer was proposed and successfully applied to constrain the oxygen fugacity of mantle ***, its application to rocks equilibrated at crustal P-T conditions has been hampered by some uncertainties in an early solid solution model of ilmenite. With a newly-released solid solution model for the ilmenite, we have conducted high-P experiments(at 3 and 5 GPa, and 900–1300°C) to test the accuracy of this oxybarometer. The experiments were performed with their oxygen fugacities controlled by the CCO buffer(i.e., C+O_2=CO_2). We demonstrated that the oxygen fugacities calculated for our high-P experimental products by using the rutile-ilmenite oxybarometer were in excellent agreement with the fO_2 dictated by the CCO buffer, suggesting a wide applicability of this oxybarometer to crust rocks. As examples, the rutile-ilmenite oxybarometer has been used to constrain the oxygen fugacities of some metamorphic rocks such as eclogite, granulite and amphibolite usually observed from the subduction zones.

关键词： High-pressure experiment Ilmenite-rutile oxybarometer Oxygen fugacity Subduction zone

Validation of Flight Control Law Based on LFT and Structured Singular Value

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Chinese Journal of Aeronautics 2007年第1期20卷 60-65页

作者： ZHOU xi liu Lin CHEN Zong-ji DUAN Hai-bin School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The main goal of flight clearance is to use the structured singular value （ μ ） analysis of the flight control system when some parameters in the system vary in a certain range. As the p-analysis can only be done on a linear fractional transformation （LFT） model, the first step of flight clearance is to generate the LFT model of the flight control system. In this paper, based on the introduction of basic theory of LFT and μ-analysis, an X-fighter is chosen as an example to utilize the proposed methods. In order to realize the flight clearance process automatically, a novel soRware package based on MATLAB programming language is developed. The results of simulation experiments validate the feasibility and effectiveness of the novel methods proposed in this paper.

关键词： flight clearance LFT g-analysis robust stability uncertain parameter

Microstructural evolution and constitutive models of 9CrMoCoB heatresistant steel during high-temperature deformation

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Journal of Iron and Steel Research International 2019年第11期26卷 1228-1239页

作者： Chao-hang Jia Chen-xi liu Yong-chang liu Chong Li Hui-jun Li Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science and EngineeringTianjin UniversityTianjin 300354China

In order to research the hot deformation behavior of 9CrMoCoB heat-resistant steel,hot compression tests were performed over a wide range of temperatures from 850 to 1150℃ and strain rates from 0.01 to 10.00 s^-*** flow stress appears to increase with the decrease in deformation temperature and the increase in strain *** relationship between microstructural evolution and deformation parameters was studied,indicating that both low strain rate and high deformation temperature appear to promote the dynamic recrystallization,while excessively high temperature with low strain rate would result in the high non-uniformity of grain *** experimental stress-strain data was applied to calculate the material constants involved in the Arrhenius-type constitutive model and the modified Zerilli-Armstrong(MZA)model,and feasibility of these two models was *** results show that the MZA model is more accurate to predict the high-temperature flow behavior of the experimental steel than the Arrhenius-type constitutive equation.

关键词： 9CrMoCoB steel-Hot deformation behavior Dynamic recrystallization Arrhenius-type constitutive model Modified Zerilli-Armstrong model

Effects of Isothermal Aging on Microstructure and Mechanical Property of Low-Carbon RAFM Steel

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Acta Metallurgica Sinica(English Letters) 2019年第9期32卷 1151-1160页

作者： Jian-Guo Chen Chen-xi liu Chen Wei Yong-Chang liu Hui-Jun Li State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Tianjin Special Equipment Inspection Institute Tianjin 300192China

In order to investigate the microstructure and mechanical property evolution of low-carbon reduced activation ferritic/martensitic(RAFM)steel during isothermal aging,the normalized and tempered specimens were aged at 600℃for 500,1000,and 3000 h,*** microstructural evolution with aging time was analyzed,including the precipitation and growth of M23C6 and MX-type carbides as well as the formation of Laves *** results indicate that the coarsening of M23C6 is more obvious than that of MX with increase in aging *** the long-term thermal exposure,the Fe2 W Laves phase precipitates adjacent to M23C6 along the prior austenite grain boundaries and packet *** carbon content can delay the precipitation of Laves phase compared to the steel containing higher *** addition,the Laves phase precipitated along boundaries can provide the precipitation strengthening,slightly increasing the tensile strength of low-carbon RAFM steel after aging for 3000 h.

关键词： Low-carbon RAFM steel Isothermal aging Microstructure evolution Mechanical property

Changes of tear film and tear secretion after phacoemulsification in diabetic patients

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第4期9卷 324-328页

作者： xi liu Yang-shun GU Ye-sheng XU Ophthalmology Center the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective: To evaluate tear film stability and tear secretion in patients with diabetes after phacoemulsification. Methods: Twenty-five diabetic cataract patients and 20 age-matched non-diabetic cataract patients as control underwent pha- coemulsification. Tear film break-up time (TFBUT), Schirmer I test (SIT), corneal fluorescein staining, and dry eye symptoms were measured pre- and postoperatively. Results: Diabetics had a decreased preoperative TFBUT and SIT. TFBUT was reduced on Day 1 and recovered on Day 180 postoperatively in both groups. SIT was increased after phacoemulsification, but returned to preoperative levels by Day 180 in non-diabetics, whereas it was lower than preoperative level in diabetics. Positive corneal fluo- rescein staining was elevated in both groups, and returned to preoperative levels only in controls. Dry eye symptoms were similar to fluorescein staining in both groups. Conclusion: Tear secretion was reduced in diabetic cataract patients after phacoe- mulsification, which worsened dry eye symptoms and predisposed those patients to ocular damage.

关键词： Phacoemulsification Diabetes Cataract Tear

Synthesis, Characterization and Properties of Poly(aryl amides) Containing Methoxy Substituted Phthalazinone Moiety

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Chinese Chemical Letters 2005年第10期16卷 1324-1326页

作者： Pei WANG Jian Dong liu xi Gao JIAN Department of Polymer Science ＆ Materials Dalian University of Technology Dalian 116012

A novel aromatic diamine, 1, 2-dihydro-2-（4-aminophenyl）-4-[3-methoxy-4-（4-aminophenoxy）]-2, 3-phthalazin-l-one （OO-DA） containing aza heterocyclic structure was synthesized from the bisphenol-like monomer in two steps and used for preparing new aromatic polyamides with high inherent viscosity of 0.89-1.03 dL.g^-1. The structures of diamine and polymers obtained were confirmed by MS, PT-IR, WAXD and ^1H-NMR. The synthesized polymers exhibited high glass transition temperature in the range of 281-307℃ and good solubility in polar solvents.

关键词： Poly(ether amides) phthalazinone solubility.

Symmetry, Reductions and New Exact Solutions of ANNV Equation Through Lax Pair

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Communications in Theoretical Physics 2008年第7期50卷 1-6页

作者： ZHANG Li-Hua liu xi-Qiang BAI Cheng-Lin Department of Mathematics Dezhou University Dezhou 253023 China School of Mathematical Sciences Liaocheng University Liaocheng 252059 China School of Physical Science and Information Engineering Liaocheng University Liaocheng 252059 China

In this paper, the direct symmetry method is extended to the Lax pair of the ANNV equation. As a result, symmetries of the Lax pair and the ANNV equation are obtained at the same time. Applying the obtained symmetry, the （2＋1）-dimensional Lax pair is reduced to （1＋1）-dimensional Lax pair, whose compatibility yields the reduction of the ANNV equation. Based on the obtained reductions of the ANNV equation, a lot of new exact solutions for the ANNV equation are found. This shows that for an integrable system, both the symmetry and the reductions can be obtained through its corresponding Lax pair.

关键词： ANNV equation direct symmetry method Lax pair reductions new exact solutions

New Multiple Soliton-like and Periodic Solutions for （2＋l）-Dimensional Canonical Generalized KP Equation with Variable Coefficients

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Communications in Theoretical Physics 2006年第5X期46卷 793-798页

作者： ZHANG Li-Hua liu xi-Qiang BAI Cheng-Lin School of Mathematical Sciences Liaocheng University Liaocheng 252059 China School of Physics Science and Information Engineering Liaocheng University Liaocheng 252059 China

In this paper, the generalized ranch function method is extended to （2＋1）-dimensianal canonical generalized KP （CGKP） equation with variable coetfficients. Taking advantage of the Riccati equation, many explicit exact solutions, which contain multiple soliton-like and periodic solutions, are obtained for the （2＋1）-dimensional OGKP equation with variable coetffcients.

关键词： (2+1)-dimensional canonical generalized (CGKP) equation with variable coefficients tanh function method Riccati equation soliton-like and periodic solutions

Synthesis and Properties of Biodegradable Copolymers of 9-Phenyl-2, 4, 8, 10-tetraoxaspiro-[5, 5]undcane-3-one and Ethylene Ethyl Phosphate

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Chinese Chemical Letters 2006年第10期17卷 1365-1368页

作者： Jian XU Zhi Lan liu Ren xi ZHUO Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Wuhan 430072

Novel biodegradable copolymer poly（CC-co-EEP） was synthesized by ring-opening copolymerization of cyclic carbonate 9-phenyl-2, 4, 8, 10-tetraoxaspiro-[5, 5]undcane-3-one （CC） and ethylene ethyl phosphate （EEP）. The obtained poly （CC-co-EEP）s were characterized by FTIR, ^1H NMR, ^13C NMR and gel permeation chromatography （GPC）. In vitro hydrolytic degradation of the copolymers were investigated in phosphate buffer solution （pH=7.4）. Hydrophilic phosphate units apparently improved the degradability of poly（carbonate-phosphate）.

关键词： Poly(carbonate-phosphate) ring-opening copolymerization biodegradable polymers.

Single-bit full adder and logic gate based on synthetic antiferromagnetic bilayer skyrmions

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Rare Metals 2022年第7期41卷 2249-2258页

作者： Kai Yu Mak Jing xia xi-Chao Zhang Li Li Mouad Fattouhi Motohiko Ezawa xiao-xi liu Yan Zhou School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China College of Physics and Electronic Engineering Sichuan Normal UniversityChengdu 610068China Department of Electrical and Computer Engineering Shinshu UniversityNagano 380-8553Japan Department of Applied Physics University of SalamancaSalamanca 37008Spain Department of Applied Physics University of TokyoTokyo 113-8656Japan

Skyrmion-based devices are promising candi-dates for non-volatile memory and low-delay time *** skyrmion-based devices execute operation by controlling skyrmion trajectory,which can be impeded by the skyrmion Hall ***,the design of skyrmion-based arithmetic devices built on synthetic antiferromag-netic(SyAF)structures is presented,where the structure can greatly suppress skyrmion Hall *** this study,the operations of skyrmion-based half adder,full adder,and XOR logic gate are executed by introducing geometric notches and tilted edges,which can annihilate or diverge *** of these skyrmion-based devices is evaluated,where the delay time and energy-delay product of the single-bit full adder are 1.95 ns and 2.50×10^(-22)Js,which are only 12%and 79%those of the previously proposed skyrmion-based single-bit full *** improvement is significant in the construction of ripple-carry adder and ripple-carry ***,our skyrmion-based SyAF arithmetic device is a promising candidate to develop high-speed spintronic devices.

关键词： Skyrmion Full adder Synthetic antiferromagnet Lowdelaytime electronics Micromagnets