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Dynamics of the Entanglement Zero Modes in the Haldane Model under a Quantum Quench

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Chinese Physics Letters 2022年第3期39卷 1-5页

作者： Heng-Xi ji Lin-Han Mo Xin wan Zhejiang Institute of Modern Physics Zhejiang UniversityHangzhou 310027China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China

We investigate evolution of entanglement spectra of the Haldane model for Chern insulators upon a sudden quench within the same topological *** particular,we focus on the location of the entanglement spectrum crossing,which signifies the bulk *** is shown that the coplanarity condition for the pseudomagnetic field of the model,which can be used to determine the crossing in the equilibrium case,needs to be *** analytically derive the non-equilibrium condition with the help of an edge-state wave function ansatz and a dynamically induced length-scale *** spectral analyses,it is realized that the oscillatory behavior of the crossing is dominated by the interband excitations at the van Hove singularities.

关键词： equilibrium topological excitation

Effect of carbon addition on creep behavior of cast TiAl alloy with hard-oriented directional lamellar microstructure

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Journal of Iron and Steel Research International 2020年第11期27卷 1347-1356页

作者： Xi-wen Zhang Yu-ling Tang Wen-juan wan.Chun-lei Zhu ji Zhang Beijing Key Laboratory of Advanced High Temperature Materials China Iron and Steel Research Institute GroupBeijing 100081China National Center for Electron Microscopy in Beijing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Two TiAl alloys,Ti-47.5Al-3.7(Cr,V,Zr)and Ti-47.5Al-3.7(Cr,V,Zr)-0.1C(at.%),were prepared by cold crucible levitation melting to couple the hard-oriented directional lamellar microstructure with carbon microalloying *** creep behavior and mechanism for the improvement in creep properties by carbon addition were investigated by mechanical tests and electron microscopy *** results show that obvious improvements on the creep properties at 760°C and 276 MPa are achieved by 0.1 at.%C addition into TiAl alloy with directional lamellar microstructure,which promotes the creep strain and minimum creep rate decreasing with a large *** minimum creep rate is reduced from 4.37×10^(-8) to 3.97×10^(-9) s^(-1),and the duration entering into creep acceleration is prolonged for more than 10 *** mechanism for creep property improvement by 0.1%C addition is attributed to two *** first one is that Ti_(2) AlC is found to be strong obstacles of 1/2[110]dislocations when moving across the lamellar interface in the carbon containing *** other one is that the in terfacial dislocatio ns are effectively impeded and the release process is hindered by dynamic precipitation of Ti_(3) AlC,which is proposed to be the special mechanism for creep resistance improvement of this hard-oriented directional lamellar microstructure.

关键词： Cast titanium aluminide Lamellar microstructure Creep behavior Carbon addition Dynamic precipitation

Calcium-handling abnormalities underlying atrial arrhythmogenesis in a Fontan operation canine model

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World Journal of Pediatrics 2018年第6期14卷 576-584页

作者： wan.Ping Zhou fen Li jin-jin Wu Ya-Nan Lu Yi-jiao Qian Cardiology Department Shanghai Children’s Medical CenterShanghai Jiaotong University School of Medicine1678 Dongfang RoadPudong New Area 200127ShanghaiChina Cardiology Department Children’s Hospital ofSooc how UniversitySuzhouChina

Background Atrial tachyarrhythmia (AT) is a common complication in patients who have undergone a Fontan operation. In this study, we investigated whether abnormal Ca2+ handling contributes to the Fontan operation-related atrial arrhythmo-genic substrate. Methods Mongrel dogs were randomly assigned to sham and Fontan groups. The Fontan operation model was developed by performing an atriopulmonary anastomosis. After 14 days, an electrophysiological study was performed to evaluate the AT vulnerability. Ca2+ handling properties were measured by loading atrial cardiomyocytes (CMs) with fura-2 AM. The L-type Ca2+ (ICa?L) and Na+–Ca2+ exchanger (INCX) currents of the CMs were recorded by the whole-cell patch-clamp technique. The key Ca2+ handling proteins expression was assessed by Western blotting. Results The AT inducibility was higher in the Fontan group than in the sham group (85.71 vs. 14.29%, P < 0.05). The Fontan operation resulted in decreased Ca2+ transient (CaT) amplitude and sarcoplasmic reticulum (SR) Ca2+ content, but in enhanced diastolic intracellular Ca2+ concentration and SR Ca2+ leak in the atrial CMs. The spontaneous CaT events, triggered ectopic activity and INCX density were increased, but ICa?L density was reduced in CMs from the Fontan atria (all P<0.05). Additionally, the Fontan operation resulted in decreased SR Ca2+ ATPase expression and Cav1.2 expression, but in increased NCX1 and Ser2814-phosphorylated ryanodine receptor 2. The calmodulin-dependent protein kinase II expres-sion and function were markedly enhanced in the Fontan atria. Conclusion The Fontan operation caused atrial CM Ca2+ handling abnormalities that produced arrhythmogenic-triggered activity and increased vulnerability to AT in experimental Fontan dogs.

关键词： Atrial tachyarrhythmia Calcium handling Fontan operation Triggered activity

Association of the genetic polymorphism of EPHX1 and EPHX2 with the susceptibility to chronic benzene poisoning

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Frontiers of Medicine 2007年第3期1卷 320-326页

作者： SUN Pin ZHANG Zhongbin WU fen wan.Junxiang jiN Xibeng XIA Zhaolin Department of Occupational Health School of Public HealthFudan UniversityShanghai 200032China

The aim of this study was to explore the association of the genetic polymorphism of EPHX1 and EPHX2 with the susceptibility to chronic benzene poisoning(CBP).A case-control study of 268 patients with CBP and 268 healthy workers matched by age and sex,all of whom were occupationally exposed to benzene,was *** single nucleotide polymorphisms(SNPs,rs2854451,rs3738047,rs2234922 and rs1051741)of EPHX1 gene and the SNP(rs751141)of EPHX2 gene were tested by the TaqMan PCR *** the subjects carrying the genotype of EPHX1 rs3738047 GG,the risk of CBP was decreased in the individuals simultaneously carrying EPHX1 rs2234922 G(P=0.02).Alternatively,in the subjects carrying the genotype of EPHX1 rs2234922 AA,the risk of CBP was increased in the individuals simultaneously carrying the allele of EPHX2 rs751141A(P=0.03).It was also found that there were potential interactions between alcohol consumption and the polymorphism of EPHX1 rs1051741(x_(H)^(2)=5.28,P=0.02)or rs2234922(x_(H)^(2)=6.71,P=0.01).Compared to individuals with EPHX1 rs1051741 CC or rs2234922 AA genotype in the drinkers,the risk of CBP in those carrying genotypes of EPHX1 rs1051741 CT+TT or rs2234922 AG+GG was decreased,respectively(P=0.04,P<0.01).Haplotype analysis of polymorphisms in EPHX1 showed that the risk of CBP was increased in the subjects with haplotype 2(rs2854451-A,rs3738047-G,rs2234922-A,rs1051741-C)or haplotype 4(rs2854451-G,rs3738047-A,rs2234922-G,rs1051741-T),but decreased in those with haplotype 6(rs2854451-G,rs3738047-G,rs2234922-G,rs1051741-T)or haplotype 10(rs2854451-A,rs3738047-A,rs2234922-G,rs1051741-T),*** regression analysis revealed that smoking might play a role in modifying the risk of CBP(OR=0.313,95%CI:0.123–0.794,P=0.015).The genetic polymorphism in EPHX1 may be associated with the risk of CBP in the Chinese occupational population and further research is needed for the association between the genetic polymorphism in EPHX2 and the susceptibility to CBP.

关键词： chronic benzene poisoning epoxide hydrolases polymorphism,single nucleotide haplotypes

Heat front propagation in shale oil reservoirs during air injection:Experimental and numerical studies

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Petroleum Science 2024年第5期21卷 3379-3389页

作者： Shuai Zhao Chun-Yun Xu wan.fen Pu Qing-Yuan Chen Cheng-Dong Yuan Mikhail A.Varfolomeev Vladislav Sudakov State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Tianfu Yongxing Laboratory Chengdu610213SichuanChina Department of Petroleum Engineering Kazan Federal UniversityKazan420008Russia Institute of Geology and Petroleum Technologies Kazan Federal UniversityKazan420008Russia Center for Petroleum Science and Engineering Skolkovo Institute of Science and TechnologyMoscow121205Russia

Air injection technique for developing shale oil has gained significant attention. However, the ability of the heat front to consistently propagate within the shale during air injection remains uncertain. To address this, we investigated the heat front propagation within oil-detritus mixtures, shale cores, and fractured shale cores using a self-designed combustion tube(CT) and experimental schemes. By integrating the results obtained from high-pressure differential scanning calorimetry and CT, we developed a comprehensive reaction kinetics model to accurately analyze the main factors influencing the heat front propagation within fractured shale. The findings revealed that in the absence of additional fractures, the heat front failed to propagate within the tight shale. The flow of gases and liquids towards the shale core was impeded, resulting in the formation of a high-pressure zone at the front region of the shale. This pressure buildup significantly hindered air injection, leading to inadequate oxygen supply and the extinguishment of the heat front. However, the study demonstrated the stable propagation of the heat front within the oil-detritus mixtures, indicating the good combustion activity of the shale ***, the heat front successfully propagated within the fractured shale, generating a substantial amount of heat that facilitated the creation of fractures and enhanced gas injection and shale oil flow. It was important to note that after the heat front passed through the shale, the combustion intensity decreased. The simulation results indicated that injecting air into the main fracturing layers of the shale oil reservoir enabled the establishment of a stable heat front. Increasing the reservoir temperature(from 63 to 143℃) and oxygen concentration in the injected gas(from 11% to 21%) promoted notable heat front propagation and increased the average temperature of the heat front. It was concluded that temperature and oxygen concentration had the mos

关键词： Heat front propagation Shale oil Kinetics model Combustion tube Air injection

Reduced precision solution criteria for nonlinear model predictive control with the feasibility-perturbed sequential quadratic programming algorithm

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第11期12卷 919-931页

作者： jiao-na wan.Zhi-jiang SHAO Ke-xin wan.Xue-yi FANG Zhi-qiang wan. ji-xin QIAN State Key Lab of Industrial Control Technology Institute of Industrial Control Department of Control Science and Engineering Zhejiang University Hangzhou 310027 China

We propose a novel kind of termination criteria, reduced precision solution (RPS) criteria, for solving optimal control problems (OCPs) in nonlinear model predictive control (NMPC), which should be solved quickly for new inputs to be applied in time. Computational delay, which may destroy the closed-loop stability, usually arises while non-convex and nonlinear OCPs are solved with differential equations as the constraints. Traditional termination criteria of optimization algorithms usually involve slow convergence in the solution procedure and waste computing resources. Considering the practical demand of solution precision, RPS criteria are developed to obtain good approximate solutions with less computational cost. These include some indices to judge the degree of convergence during the optimization procedure and can stop iterating in a timely way when there is no apparent improvement of the solution. To guarantee the feasibility of iterate for the solution procedure to be terminated early, the feasibility- perturbed sequential quadratic programming (FP-SQP) algorithm is used. Simulations on the reference tracking performance of a continuously stirred tank reactor (CSTR) show that the RPS criteria efficiently reduce computation time and the adverse effect of computational delay on closed-loop stability.

关键词： Nonlinear model predictive control (NMPC) Computational delay Termination criteria Continuously stirred tankreactor (CSTR)

The risks of sulfur addition on cadmium accumulation in paddy rice under different water-management conditions

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Journal of Environmental Sciences 2022年第8期34卷 101-111页

作者： Zhe Liu Qi-qi wan. Si-yu Huang Ling-xuan Kong Zhong Zhuang Qi wan. Hua-fen Li Ya-nan wan Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation Key Laboratory of Plant-Soil Interactions of the Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Recently, the application of sulfur(S) has been recommended to control the accumulation of cadmium(Cd) in rice in contaminated paddy soil. However, the effects of exogenous S on Cd transfer in paddy rice systems under different water-management practices have not been systematically investigated. Pot experiments were performed to monitor the composition of soil pore water and the Cd accumulation in iron plaque and rice tissue were compared under different S(0 and 200 mg/kg Na_(2)SO_(4)) and water(continuous and discontinuous flooding) treatments. Sulfur application significantly increased Cd concentrations in soil pore water under discontinuous flooding conditions, but slightly reduced them under continuous flooding. Moreover, the oxidation/reduction potential(Eh) was the most critical factor that affected the Cd levels. When the Eh exceeded-42.5 mV, S became the second critical factor, and excessive S application promoted Cd dissolution. In addition, S addition elevated the Cd levels in iron plaque and reduced the Cd transfer from the iron plaque to rice roots. In rice, S addition inhibited Cd transfer from the rice roots to the straw;thus, more Cd was stored in the rice roots. Nevertheless, additional S application increased the Cd content in the rice grains by 72% under discontinuous flooding, although this effect was mitigated by continued flooding. Under simulated practical water management conditions, S addition increased the risk of Cd contamination in rice, suggesting that S application should be reconsidered as a paddy fertilization strategy.

关键词： Rice Cadmium Sulfur Water management Iron plaque Accumulation

Molecular characteristics and temperature tolerance function of the transient receptor potential in the native Bemisia tabaci AsiaII3 cryptic species

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Journal of Integrative Agriculture 2020年第11期19卷 2746-2757页

作者： ji Shun-xia SHEN Xiao-na LIANG Lin wan. Xiao-di LIU wan.xue wan.Fang-hao LV Zhichuang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural SciencesShenzhen 518120P.R.China

Insects are poikilothermic animals,and temperature is one of the most important abiotic factors affecting their spread and *** example,differences in thermal tolerance may underlie the significant differences in geographical distributions between the native AsiaII3 and invasive MED(Mediterranean)cryptic Bemisia tabaci species in *** receptor potential(TRP)channels are key components of the insect temperature perception system and act as molecular thermometers since they can be activated by specific changes in *** this study,we cloned and characterized the AsiaII3 BtTRP gene and revealed its functions in the response to thermal *** full-length cDNA of BtTRP was 3821 bp,with a 3501-bp open reading frame encoding a 132.05-kDa *** the deduced amino acid sequences of AsiaII3 BtTRP and MED TRP revealed five amino acid *** situ hybridization indicated that BtTRP might be widely expressed throughout the AsiaII3 adult *** mRNA expression reached the highest levels after exposure to mild thermal stimuli(12 and 35°C),showing that BtTRP expression can be induced by temperature ***,the thermal tolerance of AsiaII3 after BtTRP dsRNA feeding was significantly lower than that of the *** together,the present study highlights the importance of TRP channels for *** thermal resistance,and allows us to infer that the differences in amino acids between AsiaII3 and MED might cause the differences in thermal tolerance of these two cryptic *** study provides a new direction for investigating geographic distribution differences between invasive and native insects.

关键词： transient receptor potential thermosensation thermal stress Bemisia tabaci AsiaII3

Weldability of Low Carbon Transformation Induced Plasticity Steel

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Journal of Iron and Steel Research International 2008年第5期15卷 61-65,87页

作者： ZHANG Mei LI Lin FU Ren-yu ZHANG ji-cheng wan.Zi Department of Material Science and Engineering Shanghai University Shanghai 200072 China RDC Shanghai Huizhong Automotive Manufacturing Co Ltd Shanghai 200122 China

Transformation induced plasticity （TRIP） steel exhibited high or rather high carbon equivalent （CE） because of its chemical composition, which was a particularly detrimental factor affecting weldability of steels. Thus the weldability of a TRIP steel （grade 600） containing （in mass percent, %） 0.11C-1. 19Si-1.67Mn was extensively studied. The mechanical properties and impact toughness of butt joint, the welding crack susceptibility of weld and heat affected zone （HAZ） for tee joint, control thermal severity （CTS） of the welded joint, and Y shape 60° butt joint were measured after the gas metal arc welding （GMAW） test. The tensile strength of the weld was higher than 700 MPa. Both in the fusion zone （FZ） and HAZ for butt joint, the impact toughness was much higher than 27 J, either at room temperature or at -20 ℃, indicating good low temperature impact ductility of the weld of TRIP 600 steel. In addition, welding crack susceptibility tests revealed that weldments were free of surface crack and other imperfection. All experimental results of this steel showed fairly good weldability. For application, the crossmember in automobile made of this steel exhibited excellent weldability, and fatigue and durability tests were also accomplished for crossmember assembly.

关键词： TRIP steel weldability welding crack susceptibility mechanical property impact toughness