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Effects of uniaxial compressive strain on the electronic- transport properties of zigzag carbon nanotubes

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Nano Research 2016年第5期9卷 1267-1275页

作者： Masato Ohnishi Ken Suzuki Hideo Miura Fracture and Reliability Research Institute Graduate School of Engineering Tohoku University Sendai 980-8579 Japan

Recently, substantial attention has been paid to the strain sensitivity of the carbon nanotubes＇（CNTs＇） electronic properties. In this study, the relationships between the geometric structures and electronic states of zigzag CNTs under uniaxial compressive strain were investigated. We found that different factors dominate the electronic states of zigzag CNTs depending on the strain regions： the initial stage of the strain loading, which lasts until column-buckling deformation begins, and the strain regions corresponding to column- and shell-buckling deformations. Because shell-buckling deformation significantly increases the re-orbital angle, the angle between the π orbital axis vectors of adjacent atoms, strong localization of the density of states （LDOS） occurs in the buckled area. We also analyzed the current able to pass through deformed CNTs using a tight-binding-based Green＇s function approach and determined that the current can be significantly suppressed by applying uniaxial compressive strain. Our method of predicting the electronic state of a deformed CNT based on the π-orbital angle is expected to be useful for predicting the electronic properties of CNT-based electronic devices and sensors.

关键词： carbon nanotube strain buckling deformation Green's function method electronic-transport property

On the properties of some sets of von Neumann algebras under perturbation

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Science China Mathematics 2015年第8期58卷 1707-1714页

作者： WANG LiGuang school of Mathematical sciences Qufu Normal University

Let L be a type II1 factor with separable predual and r be a normal faithful tracial state of c~. We first show that the set of subfactors of L with property F, the set of type II1 subfactors of L with similarity property and the set of all McDuff sub/actors of t are open and closed in the Hausdorff metric d2 induced by the trace norm; then we show that the set of all hyperfinite von Neumann subalgebras of L is closed in d2. We also consider the connection of perturbation of operator algebras under d2 with the fundamental group and the generator problem of type II1 factors. When M is a finite yon Neumann algebra with a normal faithful trace, the set of all von Neumann subalgebras B of M such that B ∪→ M is rigid is closed in the Hausdorff metric d2.

关键词： type II1 factor, property F, McDuff factor, hyperfinite similarity length

NONEXISTENCE AND EXISTENCE OF POSITIVE SOLUTIONS FOR 2nTH-ORDER SINGULAR SUPERLINEAR PROBLEMS WITH STRUM-LIOUVILLE BOUNDARY CONDITIONS

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Acta Mathematica Scientia 2011年第4期31卷 1569-1582页

作者：赵增勤 school of Mathematical sciences Qufu Normal University

This paper investigates a class of 2nth-order singular superlinear problems with Strum-Liouville boundary conditions. We obtain a necessary and sufficient condition for the existence of C 2 n- 2 [0, 1] positive solutions, and a sufficient condition, a necessary condition for the existence of C 2 n-1 [0, 1] positive solutions. Relations between the positive solutions and the Green’s functions are depicted. The results are used to judge nonexistence or existence of positive solutions for given boundary value problems.

关键词： 2nth-order differential equation singular boundary value problem fixed point theorem positive solution

Widening and weakening of the Hadley circulation under global warming

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Science Bulletin 2018年第10期63卷 640-644页

作者： Yongyun Hu Han Huang Chen Zhou Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking University school of Atmospheric sciences Nanjing University

The Hadley circulation is one of the most important atmospheric *** of the Hadley circulation has drawn extensive studies in the past *** key concern is that widening of the Hadley circulation would cause poleward shift of the subtropical dry *** metrics have been applied to measure the widening of the *** are responsible for the observed widening trends of the Hadley circulation? How anthropogenic and natural forcings caused the widening? How the widening results in regional climatic effects? These are the major questions in studing the widening of the Hadley *** both observations and simulations all show widening of the Hadley circulation in the past few decades,there are no general agreements of changes in the strength of the Hadley *** some reanalysis datasets show strengthening of the Hadley circulation,it was shown that the strengthening trend could be artificial,and simulations show weakening of the Hadley circulation for global greenhouse *** the present paper,we shall briefly review the major progresses of studies in trends in width and strength of the Hadley *** address answers to these questions,clarify inconsistent results,and propose ideas for future studies.

关键词： Hadley circulation Greenhouse gases Ozone depletion ENSO Global warming

The clock gene,period,influences migratory flight and reproduction of the oriental armyworm,Mythimna separata(Walker)

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Insect Science 2023年第3期30卷 650-660页

作者： Jiayue Ji Yueqiu Liu Lei Zhang Yunxia Cheng David Stanley Xingfu Jiang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina school of Landscape Architecture Bejing University of AgricultureBejingChina Biological Control of Insects Research Laboratory USDA/Agricultural Research ServiceColumbiaMOUSA

The oriental armyworm,Mythimna separata,is a major long-distance migratory insect pest of grain crops in China and other Asian *** flights and reproductive behavior usually occur at night,regulated by a circadian ***,knowledge about the linkages between adult flight,reproduction,and clock genes is still *** fill this important gap in our knowledge,a clock gene(designated Msper)was identified and phylogenetic analysis indicated that the encoded protein(MsPER)was highly similar to PER proteins from other insect *** RT-PCR assays demonstrated that significantly different spatiotemporal and circadian rhythmic accumulations of mRNA encoding MsPER occurred during development under steady 14 h:10 h light:dark *** highest mRNA accumulation occurred in adult antennae and the lowest in *** was expressed rhythmically in adult antennae,relatively less in photophase and more entering *** small interference RNA(siRNA)into adult heads effectively knocked down Msper mRNA levels within 72 *** siRNA-injected adults reduced their evening flight activity significantly and did not exhibit a normal evening peak of flight *** also failed to mate and lay eggs within 72 *** mating behavior was restored to control levels by 72 h post *** infer that Msper is a prominent clock gene that acts in regulating adult migratory flight and mating behaviors of *** of its influence on migration and mating,Msper may be a valuable gene to target for effective management of this migratory insect.

关键词： flight action Mythimna separata period clock gene reproduction RNA interference

Stability of Navier–Stokes System with Singular External Force in Fourier–Herz Space

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Acta Mathematica Sinica,English Series 2023年第7期39卷 1203-1218页

作者： De Zai MIN Qing Kai WANG Gang WU Zhuo Ya YAO school of Mathematical sciences University of Chinese Academy of SciencesBeijing 100049P.R.China

We prove the asymptotic properties of the solutions to the 3D Navier–Stokes system with singular external force, by making use of Fourier localization method, the Littlewood–Paley theory and some subtle estimates in Fourier–Herz space. The main idea of the proof is motivated by that of Cannone et al. [J. Differential Equations, 314, 316–339(2022)]. We deal either with the nonstationary problem or with the stationary problem where solution may be singular due to singular external force. In this paper, the Fourier–Herz space includes the function space of pseudomeasure type used in Cannone et al. [J. Differential Equations, 314, 316–339(2022)]

关键词： 3D Navier–Stokes equations Fourier–Herz spaces singular external force Littlewood–Paley theory stability

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Curvature-regulated transmembrane anion transport by a trifluoromethylated bisbenzimidazole

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Chinese Chemical Letters 2021年第5期32卷 1653-1656页

作者： Xiao-Qiao Hong Yuan-Yuan Xing Zhong-Kun Wang Qin-Chao Mao Wen-Hua Chen school of Biotechnology and Health sciences Wuyi UniversityJiangmen 529020China school of Pharmaceutical sciences Tsinghua UniversityBeijing 100084China Guangdong Maoming Health Vocational College Maoming 525000China State Key Laboratory of Chemical Oncogenomics Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China

In this paper,we demonstrate that modification of anion-transport:active l,3-bis(benzimidazol-2-yl)benzene with strongly electron-withdrawing trifluoromethyl and nitro groups leads to a dramatic increase in the aniono... 详细信息

关键词： Anion transporter Lysosomal curvature Anionophoric activity

On cutting sequences of the L-shaped translation surface tiled by three squares

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Science China Mathematics 2015年第6期58卷 1311-1326页

作者： WU ShengJian ZHONG YuMin LMAM and school of Mathematical sciences Peking University

We consider a symbolic coding of bi-infinite non periodic geodesics on the L-shaped translation surface tiled by three squares. Each bi-infinite non periodic geodesic is associated with a cutting sequence corresponding to the sequence of labeled saddle connections hit. We prove that there is a relationship between the cutting sequences and the actions of some affine automorphisms of the translation surface. We also get an explicit formula to determine the direction of a bi-infinite non periodic geodesic by using the corresponding cutting sequence.

关键词： affine shaped cutting labeled intersection letter infinite compatible saddle explicit

Condensation of STM is critical for shoot meristem maintenance and salt tolerance in Arabidopsis

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Molecular Plant 2023年第9期16卷 1445-1459页

作者： Xiuwei Cao Qingwei Du Yahe Guo Ying Wang Yuling Jiao State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(Beijing) Institute of Genetics and Developmental BiologyThe Innovative Academy of Seed DesignChinese Academy of SciencesBeijing 100101China College of Life sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China Peking-Tsinghua Center for Life sciences Center for Quantitative BiologyAcademy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China Peking University Institute of Advanced agricultural sciences Shandong Laboratory of Advanced Agricultural Sciences in WeifangWeifangShandong 261325China College of Advanced agricultural sciences University of Chinese Academy of SciencesBeijing 100049China

The shoot meristem generates the entire shoot system and is precisely maintained throughout the life cycle under various environmental *** this study,we identified a prion-like domain(PrD)in the key shoot meristem regulator SHOOT MERISTEMLESS(STM),which distinguishes STM from other related KNOX1 *** demonstrated that PrD stimulates STM to form nuclear condensates,which are required for maintaining the shoot *** nuclear condensate formation is stabilized by selected PrD-containing STM-interacting BELL proteins in vitro and in ***,condensation of STM promotes its interaction with the Mediator complex subunit MED8 and thereby enhances its transcriptional ***,condensate formation emerges as a novel regulatory mechanism of shoot meristem ***,we found that the formation of STM condensates is enhanced upon salt stress,which allows enhanced salt tolerance and increased shoot *** findings highlight that the transcription factor partitioning plays an important role in cell fate determination and might also act as a tunable environmental acclimation mechanism.

关键词： intrinsically disordered proteins KNOX1 shoot apical meristem biomolecular condensate salt stress axillary meristem