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Ferroelectricity survives in the sub-nanometer scale

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Science China Materials 2023年第5期66卷 2105-2106页

作者： Yiqian Liu yuan-Hua lin State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Ultrathin materials with maintained functionalities are the prerequisites for the device miniaturization and *** materials are key ingredients in nonvolatile memories as information storage media and in field-effect transistors as gate dielectrics[1],and therefore their thickness scaling enables the high-capacity and energy-efficient ***,the longstanding problem for ultrathin ferroelectrics is that the strong depolarizing field can cancel ferroelectricity[2].In traditional barium titanates,the ultrathin film turns paraelectric without spontaneous polarizations[2,3].Moreover,realizing switchable ferroelectric behaviors is even more challenging because of the unsuppressed leakage *** recent years,although some studies have demonstrated that ferroelectricity can be stabilized in several nanometers in perovskites and fluorites[4-6],there still lacks direct evidence to confirm that ultrathin ferroelectrics have macroscopic hysteresis loops and polarization switching,which is the foundation of the practical usage of ultrathin ferroelectrics.

关键词： polarization ferroelectric maintained

A solution to parabolic system with the fractional Laplacian

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 184-190页

作者： FANG lin FANG Dao-yuan Dept. of Math. Zhejiang Univ. Hangzhou 310027 China

The existence of a solution to the parabolic system with the fractional Laplacian （-△） α/2, α 〉 0 is proven, this solution decays at different rates along different time sequences going to infinity. As an application, the existence of a solution to the generalized Navier-Stokes equations is proven, which decays at different rates along different time sequences going to infinity. The generalized Navier-Stokes equations are the equations resulting from replacing -△ in the Navier-Stokes equations by （-△）^m, m〉 0. At last, a similar result for 3-D incompressible anisotropic Navier-Stokes system is obtained.

关键词： parabolic system fractional Laplacian decay rate

Multilinear Singular Integral Operators with Generalized Kernels and Their Multilinear Commutators

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Acta Mathematica Sinica,English Series 2017年第11期33卷 1443-1462页

作者： Yan lin Ya yuan XIAO School of Sciences China University of Mining and Technology Department of Mathematical Sciences Ball State University

In this paper, the authors study a class of multilinear singular integral operators with generalized kernels and their multilinear commutators with BMO functions. By establishing the sharp maximal estimates, the boundedness on product of weighted Lebesgue spaces and product of variable exponent Lebesgue spaces is obtained, respectively. Moreover, the endpoint estimate of this class of mutilinear singular integral operators is also established. These results can improve the corresponding known results of classical multilinear Calder6n-Zygmund operators and multilinear Calderon-Zygmund operators with Dini type kernels.

关键词： Multilinear singular integral sharp maximal function multilinear commutator BMO function

Global Spherically Symmetric Solutions for a Coupled Compressible Navier–Stokes/Allen–Cahn System

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2037-2064页

作者： Chang Ming SONG Jian lin ZHANG yuan yuan WANG Department of Applied Mathematics School of Mathematics and Information ScienceZhongyuan University of TechnologyZhengzhou 450007P.R.China

In this paper,we consider the global spherically symmetric solutions for the initial boundary value problem of a coupled compressible Navier–Stokes/Allen–Cahn system which describes the motion of two-phase viscous compressible *** prove the existence and uniqueness of global classical solution,weak solution and strong solution under the assumption of spherically symmetry condition for initial dataρ0 without vacuum state.

关键词： Diffuse interface model global solutions Navier-Stokes equations Allen-Cahn equation spherically symmetry

Rh(Ⅰ)-catalyzed borylation of primary alkyl chlorides

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Chinese Chemical Letters 2014年第3期25卷 397-400页

作者： Tian-Jun gong yuan-Ye Jiang Yao Fu Department of Chemistry University of Science and Technology of China

Rhodium-catalyzed cross-coupling reactions of unactivated primary alkyl chlorides with diboron reagents have been developed as practical methods for the synthesis of alkylboronic esters. These reactions expand the con... 详细信息

关键词： Alkyl chloridesRh(l)-catalyzedCross-couplingAlkylboronic esters

Degradation kinetics and products of triazophos in intertidal sediment

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Journal of Environmental Sciences 2005年第6期17卷 933-936页

作者： lin Kun-de yuan Dong-xing Institute of Environmental Science Zhejiang University Hangzhou 310029 China State Key Laboratory of Marine Environmental Science Environmental Science Research Center Xiamen University Xiamen 361005 China

This work presents taboratory studies on the degradation of triazophos in intertidat sediment. The overall degradations were found to follow the first-order decay model. After being incubated for 6 d, the percentage of degradations of triazophos in unsterilized and sterilized sediments were 94.5% and 20.5%, respectively. Between the temperatures of 15℃ and 35℃, the observed degradation rate constant（kob,d） enhanced as the incubation temperature increased. Triazophos in sediment degraded faster under aerobic condition than under anaerobic one. The water content of sediment had little influence on the degradation when it was in the range of 50%-100%. The values of kobsd decreased with increasing initial concentration of triazophos in sediment, which could result from the microorganism inhibition by triazophos. Four major degradation products, o, o-diethyl phosphorothioic acid, monoethyl phosphorothioic acid, phosphorothioic acid, and 1-phenyl-3-hydroxy-1, 2,4-triazole, were tentatively identified as their corresponding trimethylsilyl derivatives with a gas chromatography-mass spectrometer. The possible degradation pathway of triazophos in intertidal sediment was proposed. The results revealed that triazophos in intertidal sediment was relatively unstable and coutd be easily degraded.

关键词： triazophos degradation intertidal sediment

Novel fibronectin-targeted nanodisk drug delivery system displayed superior efficacy against prostate cancer compared with nanospheres

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Nano Research 2019年第10期12卷 2451-2459页

作者： Luyao Wang Bingjie Zhou Shiqi Huang Mengke Qu Qing lin Tao gong yuan Huang Xun Sun Qin He Zhirong Zhang ling Zhang Key Laboratory of Drug Targeting and Drug Delivery Systems Ministry of EducationWest China School of PharmacyCollege of Polymer Science and EngineeringSichuan UniversityChengdu 610041China

Currently,prostate cancer is the most frequently diagnosed cancer in males and chemotherapy is often essential for treating advaneed prostate ***,common chemotherapies for prostate cancer suffer from serious adverse effects due to poor drug targeting ability and tissue penetration,even with the help of conventional drug delivery ***,encouraged by recent studies showing possible drug retention and tissue pen etration advan tages of unconventional non-spherical nan oparticles over conventional spherical nan oparticles,we design and construct a novel non-spherical nano disk drug delivery system for treating prostate *** to enhance tumor-targeting capability,these nanodisks are further modified with targeting peptide,Cys-Arg-Glu丄ys?Ala peptide with N-methylated Glu(CR(NMe)EKA),which recognizes extracellular matrix fibronectin and its complexes specifically expressed on the walls of tumor vessels and in tumor *** with conventional nano spheres,the nano disks achieve much higher drug accumulati on at prostate tumor *** loaded with paclitaxel,the CR(NMe)EKA-modified nan odisks display superior an titumor efficacy to free paclitaxel,unmodified nan odisks and nano *** summary,our study provides an attractive therapeutic strategy for targeted therapy against prostate cancer with simple preparation,high efficiency and low toxicity,and supplements a theoretical support for treatments realized by different shaped nano *** study also offers valuable data for understa nding biological effects of non-spherical nano disks and highlights the great pote ntial of unconventional nan oparticles in biomedical applicati ons.

关键词： Cys-Arg-Glu-Lys-Ala peptide with N-methylated Glu(CR(NMe)EKA) fibronectin nanodisks prostate cancer tumor-targeting

The Yield and Water Use Efficiency to First Cutting Date of Siberian Wildrye in North China

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Agricultural Sciences in China 2011年第11期10卷 1716-1722页

作者： LI Zi-zhong ZHANG Wei-hua gong yuan-shi Department of Soil and Water Sciences China Agricultural University Beijing 100193 P.R.China

A field experiment study was conducted in Bashang Plateau in North China in 2008 to determine the effect of three first cutting dates on the growth and water use efficiency （WUE） of Siberian wildrye （Elymus sibiricus L.） in the agropastoral ecotone of North China （APENC）. The experiment was conducted in a split plot design with three replications with water supply regime as the main plot treatment and first cutting date as the subplot treatment. Two water supply regimes were used, which included rain-fed treatment as control （CK） and a single irrigation and straw mulch treatment （W）. Three first cutting date treatments were conducted at early heading stage on July 1 （E）, at late heading stage on July 12 （L）, and at flowering stage on July 27 （F）, respectively. The results showed that the forage yield and WUE were the lowest at early heading stage harvest, while the highest at flowering stage either in CK or W treatment. Under combined CK and W treatments, average forage yields of the F subplots were 2 900 and 6 703 kg ha-~, and the values of WUE were 0.82 and 2.28 kg m-3, respectively. Under the CK treatment, forage yields of the E and L subplots were 43.8 and 41.9% lower than the F subplots, and their values of WUE were 46.2 and 50.3% lower than F, respectively. Under the W treatment, the forage yields of the E and L subplots were 74.9 and 61.6% lower, and their values of WUE were 78.1 and 63.3% lower, respectively, as compared with F subplots. Therefore, earlier first cutting did not increase the regrowth of Siberian wildrye and improve the mismatch between rainy season and the period of high growth potential of the grass in the semiarid APENC.

关键词： siberian wildrye first cutting date forage yield water use efficiency North China

Time-Periodic Solution to the Compressible Navier–Stokes/Allen–Cahn System

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Acta Mathematica Sinica,English Series 2020年第4期36卷 419-442页

作者： Chang Ming SONG Jian lin ZHANG yuan yuan WANG Department of Applied Mathematics College of ScienceZhongyuan University of TechnologyZhengzhou 450007P.R.China

In this paper,we investigate the time-periodic solution to a coupled compressible Navier–Stokes/Allen–Cahn system which describes the motion of a mixture of two viscous compressible fluids with a time periodic external force in a periodic domain in R^*** existence of the time-periodic solution to the system is established by using an approach of parabolic regularization and combining with the topology degree theory,and then the uniqueness of the period solution is obtained under some smallness and symmetry assumptions on the external force.

关键词： Navier–Stokes equation Allen–Cahn equation two-phase flows time-periodic solution topology degree theory