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Manipulating submolecular-scale phototautomerization

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Science China Materials 2024年第6期67卷 2048-2050页

作者： ping zhou Hongliang Chen Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310058China Zhejiang-Israel Joint Laboratory of Self-Assembling Functional Materials ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311215China

A recent study on the submolecular-scale control of phototautomerization methods and the underlying reaction mechanisms was reported in Nature Nanotechnology by Guillaume and co-workers[1],elucidating how the field confinement effect generated by the scanning tunneling microscope(STM)tip precisely triggers the phototautomerization of a free-base phthalocyanine at the submolecular level and demonstrating that the reaction process can be finely controlled by adjusting either the laser excitation wavelength or the position of the tip.

关键词： tunneling excitation phthalocyanine

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四角田隧道围岩稳定性三维有限元数值分析

重庆建筑大学学报 2006年第1期28卷 59-62页

作者：周小平徐小敏重庆大学土木工程学院重庆400045

云南大保高速公路四角田隧道地处峡谷地带,工程地质条件比较复杂,且地表水丰富。结合四角田隧道的工程实况,利用Drucker-Prager屈服准则,运用有限元法对该隧道进行三维非线性有限元模拟分析,以评价其整体稳定性。根据计算分析结果,指出... 详细信息

云南大保高速公路四角田隧道地处峡谷地带,工程地质条件比较复杂,且地表水丰富。结合四角田隧道的工程实况,利用Drucker-Prager屈服准则,运用有限元法对该隧道进行三维非线性有限元模拟分析,以评价其整体稳定性。根据计算分析结果,指出了隧道的相对危险区域,确定了实地重点监测的范围,同时对同类工程也具有一定的指导意义。

关键词：四角田隧道围岩稳定性三维非线性有限元

Producing circularly polarized luminescence by radiative energy transfer from achiral metal-organic cage to chiral organic molecules

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Chinese Chemical Letters 2024年第8期35卷 498-502页

作者： Zhao-Xia Lian Xue-Zhi Wang Chuang-Wei zhou Jiayu Li Ming-De Li xiao-ping zhou Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou 510632China College of Chemistry and Chemical Engineering Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China

The development of circularly polarized luminescence(CPL)materials with high performance is signifi-cantly ***,we develop a facial strategy for fabricating a CPL-active system by employing an achiral luminescent metal-organic cage(MOC)and chiral boron dipyrromethene(BODIPY)*** is achieved by taking advantage of the radiative energy transfer process,in which BODIPY molecules act as energy acceptors and MOCs act as *** CPL performance(maximum luminescence dissymme-try factor up to±1.5×10^(−3))can be tuned by adjusting the ratio between MOCs and ***-light emission with the CPL feature is obtained by using a ternary system including MOC,chiral BODIPY,and Rhodamine *** present work provides a facile and universal strategy to construct a CPL-active system by integrating achiral luminophores and chiral molecules.

关键词： Circularly polarized luminescence Metal-organic cage Radiative energy transfer Chiral small molecules Bodipy Chirality

An adaptive energy regulation in a memristive map linearized from a circuit with two memristive channels

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Communications in Theoretical Physics 2024年第3期76卷 42-50页

作者： Feifei Yang ping zhou Jun Ma School of Science Chongqing University of Posts and TelecommunicationsChongqing 430065China College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Physics Lanzhou University of TechnologyLanzhou 730050China

Nonlinear circuits can show multistability when a magnetic flux-dependent memristor(MFDM) or a charge-sensitive memristor(CSM) is incorporated into a one branch circuit,which helps estimate magnetic or electric field *** this paper,two different kinds of memristors are incorporated into two branch circuits composed of a capacitor and a nonlinear resistor,thus a memristive circuit with double memristive channels is *** circuit equations are presented,and the dynamics in this oscillator with two memristive terms are ***,the memristive oscillator is converted into a memristive map by applying linear transformation on the sampled time series for the memristive *** Hamilton energy function for the memristive oscillator is obtained by using the Helmholtz theorem,and it can be mapped from the field energy of the memristive *** energy function for the dual memristive map is suggested by imposing suitable weights on the discrete energy *** dynamical behaviors of the new memristive map are investigated,and an adaptive law is proposed to regulate the firing mode in the memristive *** work will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map energy calculation.

关键词： Hamilton energy dual memristive map adaptive energy regulation

Study of baryon number transport dynamics and strangeness conservation effects using Ω-hadron correlations

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Nuclear Science and Techniques 2024年第7期35卷 147-156页

作者： Wei-Jie Dong xiao-zhou Yu Si-Yuan ping Xia-Tong Wu Gang Wang Huan-Zhong Huang Zi-Wei Lin Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Department of Physics and Astronomy University of CaliforniaLos AngelesCA 90095USA Department of Physics East Carolina UniversityGreenvilleNC 27858USA

In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been transported from the incident nuclei and/or produced in the baryon-pair production of Ω with other types of anti-hyperons such as Ξ. To investigate these two scenarios, we propose to measure the correlations between Ω and K and between Ω and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport(AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the Ω-hadron correlations from simulated Au+Au collisions at ■ =7.7 and 14.6 Ge V and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions.

关键词： Baryon number transport Strangeness conversation Correlation Gluon junction

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无单元法研究现状及展望

工程力学 2005年第1期22卷 12-20页

作者：周小平周瑞忠福州大学土木建筑工程学院福州350002

无单元法是众多无网格方法中较有代表性的一种,形式简单、明确,计算精度高。因其具有仅需离散的结点信息、解答具有高次连续性、能较好地反映应力高梯度分布并便于跟踪裂纹的扩展过程等优点,无单元法自问世以来获得了广泛的重视,已成为... 详细信息

无单元法是众多无网格方法中较有代表性的一种,形式简单、明确,计算精度高。因其具有仅需离散的结点信息、解答具有高次连续性、能较好地反映应力高梯度分布并便于跟踪裂纹的扩展过程等优点,无单元法自问世以来获得了广泛的重视,已成为计算力学领域的一个研究热点。文中着重分析了无单元法研究中的热点问题及解决方法,介绍了该方法目前的一些应用范围,并指出其可能的发展方向。

关键词：计算力学无单元法综述无网格方法滑动最小二乘法

Phase field modeling of grain stability of nanocrystalline alloys by explicitly incorporating mismatch strain

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Rare Metals 2024年第7期43卷 3370-3382页

作者： Min zhou Hong-Hui Wu Yuan Wu Hui Wang Xiong-Jun Liu Sui-He Jiang xiao-Bin Zhang Zhao-ping Lu Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083Cnina Institute for Carbon Neutrality University of Science and TechnologyBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Ab st ra ct Nanocrystalline materials exhibit unique properties due to their extremely high grain boundary(GB) ***,this high-density characteristic induces grain coarsening at elevated temperatures,thereby limiting the widespread application of nanocrystalline *** experimental observations revealed that GB segregation and second-phase pinning effectively hinder GB migration,thereby improving the stability of nanocry stalline *** this study,a mouified phase-field model that integrates mismatch strain,solute segregation and precipitation was developed to evaluate the influence of lattice misfit on the thermal stability of nanocrystalline *** simulation results indicated that introducing a suitable mismatch strain can effectively enhance the microstructural stability of nanocrystalline *** synergizing precipitation with an appropriate lattice misfit,the formation of second-phase particles in the bulk grains can be suppressed,thereby facilitating solute segregation/precipitation at the *** concentrated solute segregation and precipitation at the GBs effectively hinders grain migration,thereby preventing grain *** findings provide a new perspective on the design and regulation of nanocrystalline alloys with enhanced thermal stability.

关键词： Phase field model Mismatch strain Second-phase precipitation Grain boundary segregation Nanocrystalline alloys

Impact of frailty on short-term postoperative outcomes in patients undergoing colorectal cancer surgery:A systematic review and meta-analysis

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 893-906页

作者： Yao zhou xiao-Lei Zhang Hong-Xia Ni Tian-Jing Shao ping Wang Department of Operating Room Affiliated Tumor Hospital of Nantong University&Nantong Tumor HospitalNantong 226361Jiangsu ProvinceChina Department of Gastrointestinal Surgery The Affiliated Tumor Hospital of Nantong University&Nantong Tumor HospitalNantong 226361Jiangsu ProvinceChina

BACKGROUND Colorectal cancer is a major global health challenge that predominantly affects older *** management,despite advancements,requires careful consideration of preoperative patient status for optimal *** To summarize existing evidence on the association of frailty with short-term postoperative outcomes in patients undergoing colorectal cancer *** A literature search was conducted using PubMed,EMBASE and Scopus databases for observational studies in adult patients aged≥18 years undergoing planned or elective colorectal surgery for primary carcinoma and/or secondary *** studies that conducted frailty assessment using recognized frailty assess-ment tools and had a comparator group,comprising nonfrail patients,were *** effect sizes were reported as weighted mean difference or relative risk(RR)with 95%confidence intervals(CIs).RESULTS A total of 24 studies were *** with nonfrail patients,frailty was associated with an increased risk of mortality at 30 d(RR:1.99,95%CI:1.47-2.69),at 90 d(RR:4.76,95%CI:1.56-14.6)and at 1 year(RR:5.73,95%CI:2.74-12.0)of follow *** patients had an increased risk of any complications(RR:1.81,95%CI:1.57-2.10)as well as major complications(Clavien-Dindo classification grade≥III)(RR:2.87,95%CI:1.65-4.99)compared with the control *** risk of reoperation(RR:1.18,95%CI:1.07-1.31),readmission(RR:1.70,95%CI:1.36-2.12),need for blood transfusion(RR:1.67,95%CI:1.52-1.85),wound complications(RR:1.49,95%CI:1.11-1.99),delirium(RR:4.60,95%CI:2.31-9.16),risk of prolonged hospitalization(RR:2.09,95%CI:1.22-3.60)and discharge to a skilled nursing facility or rehabilitation center(RR:3.19,95%CI:2.0-5.08)was all higher in frail *** Frailty in colorectal cancer surgery patients was associated with more complications,longer hospital stays,higher reoperation risk,and increased *** frailty assessment appears crucial for tailored surgical managem

关键词： Frailty Frail adults Colorectal surgery Colorectal cancer Complications Mortality Survival Slinical outcomes Meta-analysis

用Voronoi图进行新型自然邻居插值的几何学方法与特性

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计算力学学报 2005年第3期22卷 355-359页

作者：周小平周瑞忠福州大学土木建筑工程学院福建福州350002

新的基于Voronoi图的NaturalNeighbour插值是自然单元法的数学基础,也是一种新型的几何插值方法,具有与其他传统常用插值不同的构造方法,并表现出一定的优越性。本文介绍了基于NaturalNeighbour关系的Sibson插值和non-Sibsonian插值,并... 详细信息

新的基于Voronoi图的NaturalNeighbour插值是自然单元法的数学基础,也是一种新型的几何插值方法,具有与其他传统常用插值不同的构造方法,并表现出一定的优越性。本文介绍了基于NaturalNeighbour关系的Sibson插值和non-Sibsonian插值,并与有限元法和无单元法所用的插值方法,就离散插值方案和网格总体特性、形函数支撑域、本征边界条件、空间维数扩展与计算工作量等诸问题进行了比较分析。

关键词：自然单元法自然邻居插值 Sibson插值 non—Sibsonian插值 Voronoi图