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Molecular design for enhanced spin transport in molecular semiconductors

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Nano Research 2023年第12期16卷 13457-13473页

作者： Tingting Yang Yang Qin xianrong gu Xiangnan Sun Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Molecular semiconductors(MSCs),characterized by a longer spin lifetime than most of other materials due to their weak spin relaxation mechanisms,especially at room temperature,together with their abundant chemical tailorability and flexibility,are regarded as promising candidates for spintronic applications.Molecular spintronics,as an emerging subject that utilizes the unique properties of MSCs to study spin-dependent phenomena and properties,has attracted wide attention.In molecular spintronic devices,MSCs play the role as medium for information transport,process,and storage,in which the efficient spin inject–transport process is the prerequisite.Herein,we focus mainly on summarizing and discussing the recent advances in theoretical principles towards spin transport of MSCs in terms of the injection of spin-polarized carriers through the ferromagnetic metal/MSC interface and the subsequent transport within the MSC layer.Based on the theoretical progress,we cautiously present targeted design strategies of MSCs that contribute to the optimization of spin-transport efficiency and give favorable approaches to exploring accessional possibilities of spintronic materials.Finally,challenges and prospects regarding current spin transport are also presented,aiming to promote the development and application of the rosy and energetic field of molecular spintronics.

关键词： molecular spintronics molecular semiconductors spin transport spin injection molecular design

High-performance floating-gate organic phototransistors based on n-type core-expanded naphthalene diimides

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Chinese Chemical Letters 2023年第3期34卷 465-468页

作者： xianrong gu Yang Qin Su Sun Lidan guo Xiangwei Zhu Xiangnan Sun Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China

In the field of organic phototransistor, achieving both broad-spectral and high photosensitivity has always been a big challenge. The innovation of device structure has previously proven to be a possible solution to this problem. Here in this study, a novel organic phototransistor based on a high mobility n-type small molecule as the conducting layer and an isolated bulk heterojunction light-absorbing layer as the floating gate has been demonstrated in this study. With the special designed device structure, the phototransistor shows extremely high sensitivity to broad spectral and weak light irradiation, and the photoresponsivity and photocurrent/dark-current ratio of the device can reach up to 4840 mA/W and 1.8×10~5 respectively.For conclusion, this study suggests a potential way to obtain high-performance phototransistors at room temperature, which will further promote the commercial application of organic phototransistors.

关键词： Organic phototransistor Bulk heterojunction n-Type small molecule Broad spectral photoresponse Weak light irradiation

NUMERICAL CALCULATION AND APPLICATION OF CNOIDAL WAVE THEORY

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China Ocean Engineering 1989年第4期4卷 385-398页

作者： gu, Jialong Shen, xianrong East China Technical Univ of Water Resources China

In this paper expressions for the solution and general properties (wave energy, radiation stress, etc.) of the first-order cnoidal wave theory are given as a power series of the complementary modulus of the theta function. These expressions are convenient for numerical calculation because they converge very rapidly over the applicable range of Ursell number (Us> 10) for the theory. As examples of practical application, the relative height of wave crest, maximum bottom velocity, radiation stress, wave set-down and set-up are calculated. Comparisons between calculated values and experimental data are made.

关键词： Data Processing Natural Sciences Applications Stresses Calculations

Wave Decay and Its Characteristics in Surf Zone

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China Ocean Engineering 1991年第2期6卷 139-152页

作者： gu, Jialong Shen, xianrong Hohai Univ Nanjing China

In accordance with the similarity between breaking waves and hydraulic jumps, the expressions for estimating wave decay and wave energy dissipation in the surf zone are derived based on the fundamental equations of fluid mechanics. Using the numerical solution of cnoidal wave theory, the various kinematic properties of waves in the surf zone, including the relative wave crest height, wave energy, and radiation stress are discussed. The values calculated with the method proposed in this paper are in good agreement with the experimental data gained by other researchers. The present expressions can be used in the studies of sediment transport on gently sloping beaches, especially on muddy beaches.

关键词： Beaches Fluid Mechanics Hydraulic Jump

Spatial and temporal distribution of Neolithic sites in coastal China:Sea level changes, geomorphic evolution and human adaption

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Science China Earth Sciences 2018年第2期61卷 123-133页

作者： ZHENG HongBo ZHOU YouSheng YANG Qing HU ZhuJun LING guangJiu ZHANG JuZhong gu Chunguang WANG YingYing CAO YeTing HUANG xianrong CHENG Yue ZHANG XiaoYu WU WenXiang Research Center for Earth System Science Yunnan University School of Geography Science Nanjing Normal University Department for the History of Science and Scientific Archaeology University of Science and Technology of China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

The East China coastal plain is one of the most important Neolithic culture areas in China, where rich archaeological sites including those producing the earliest domesticated rice are observed. It is also a place where landscape has experienced dramatic evolution during the Holocene when both sea level and climate changed, such that it is an ideal place for studying human-environment interaction. This study investigated over 2000 sites of pre-history and Shang and Zhou Dynasties, with 655 of which being Neolithic ages, by using DEM and GIS methods. The results suggest that the spatial and temporal distribution of Neolithic sites has largely been controlled by landscape evolution(particularly changes in coastal line), which ultimately governed by sea level changes. During early Holocene, Neolithic sites sparsely distributed in the intermountain basins of east Zhejiang Province, far from the influence of ocean. Over the period of 9–7 ka, the coastal plain(including the shelf) was largely submerged,only the feet of low hills to the south and southwest of the study area, and islands protruding the estuary, cradled limited number of settlements with characteristic "maritime components". At about 7 ka, sea level rise decelerated prominently, while sediments supply in the drainage remained high value, the combination of which led to land formation and propagation. Vast space during this period facilitated the growth of settlements in both size and number. In the mean time, however, the coastal plain was vulnerable to extreme environmental events such as storms and flooding owning to its geomorphic nature, which exerted great influence on the rise and fall of Neolithic culture.

关键词：水平变化地球形状地点沿海空间时间进化中国

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数字平台经济竞争与垄断的微观基础研究

社会科学研究 2023年第1期 123-132页

作者：于伟古中博易宪容青岛大学经济学院山东青岛266071

数字化技术引致人类社会划时代的变革及人的理性行为选择方式质的飞跃,由此形成了新的生产要素、新的资源配置方式、新的产业组织形式等,并驱动了经济的微观基础发生根本性变革。数字平台厂商(DPM)是这种根本性变革的主要载体,其竞争与... 详细信息

数字化技术引致人类社会划时代的变革及人的理性行为选择方式质的飞跃,由此形成了新的生产要素、新的资源配置方式、新的产业组织形式等,并驱动了经济的微观基础发生根本性变革。数字平台厂商(DPM)是这种根本性变革的主要载体,其竞争与垄断方式也出现根本性变化。DPM的本质特征是网络效应,DPM之间的竞争本质上就是策展机制的竞争。策展机制是指通过数字化智能技术进行有效的内外治理,拓展与深化积极网络效应,减少消极网络效应。DPM若没有网络规模难以成功,但占有巨大的市场份额的DPM同样可能出现凹型崩溃。所以,传统经济理论中的市场结构、市场占有率、市场支配地位等概念并不适于评估DPM是否垄断,而可竞争性则是一个可选择的概念。当前,对于平台厂商反垄断的治理和监管,重点应放在促进DPM的创新、可竞争性和行为规范上。

关键词：数字平台厂商 DPM垄断与竞争网络效应策展机制可竞争性

桥梁断面颤振导数识别的协方差块Hankel矩阵法

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同济大学学报（自然科学版） 2007年第5期35卷 587-591页

作者：祝志文顾明秦仙蓉同济大学土木工程防灾国家重点实验室

采用基于协方差块Hankel矩阵(covariance block Hankel matrix,CBHM)方法来处理节段模型风洞试验的二自由度振动衰减信号,通过系统识别来提取桥梁断面的颤振导数.为验证该方法的可行性,进行了实际桥梁断面的节段模型试验,并将识别的颤... 详细信息

采用基于协方差块Hankel矩阵(covariance block Hankel matrix,CBHM)方法来处理节段模型风洞试验的二自由度振动衰减信号,通过系统识别来提取桥梁断面的颤振导数.为验证该方法的可行性,进行了实际桥梁断面的节段模型试验,并将识别的颤振导数与Theodorson理想平板解析解、特征系统实现法(eigensystem realization algorithm,ERA)结果进行了比较,颤振导数的一致性证明了本文方法的有效性.

关键词：桥梁断面颤振风洞试验系统识别协方差块Hankel矩阵方法

刚度、阻尼矩阵非对称性对气动导数识别的影响

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同济大学学报（自然科学版） 2007年第10期35卷 1305-1309页

作者：王雄江秦仙蓉顾明同济大学土木工程防灾国家重点实验室上海200092 同济大学机械工程学院上海200092

针对桥梁结构节段模型风洞测振试验中因风的作用而导致的系统刚度矩阵和阻尼矩阵的非对称性可能影响识别结果这一问题,利用状态空间法仿真薄平板模型在均匀风场中的自由衰减响应和紊流场中的抖振响应,分别采用特征实现算法(ERA)和随机... 详细信息

针对桥梁结构节段模型风洞测振试验中因风的作用而导致的系统刚度矩阵和阻尼矩阵的非对称性可能影响识别结果这一问题,利用状态空间法仿真薄平板模型在均匀风场中的自由衰减响应和紊流场中的抖振响应,分别采用特征实现算法(ERA)和随机子空间法(SSI),识别出均匀流场和紊流风场中的理想薄平板模型气动导数.通过与仿真所用的薄平板模型的气动导数理论值的对比,确定等效刚度矩阵和等效阻尼矩阵的非对称性对系统识别方法所得结果的影响.仿真结果表明,目前,应用比较广泛的ERA方法和SSI方法,均对阻尼矩阵和刚度矩阵的非对称性具有足够的适应性.

关键词：桥梁结构气动导数系统识别特征实现算法随机子空间法

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紊流风场中桥梁气动导数识别的随机方法

土木工程学报 2005年第4期38卷 73-77页

作者：秦仙蓉顾明同济大学土木工程防灾国家重点实验室

气动导数是大跨桥梁结构颤振和抖振分析的重要依据。本文提出采用随机系统识别方法来识别紊流风场中的气动导数, 与当前应用较广的瞬态激励法及强迫激励法相比, 这类方法的优势在于: (1) 将紊流看作是激励, 而不是噪声, 更能反映结构... 详细信息

气动导数是大跨桥梁结构颤振和抖振分析的重要依据。本文提出采用随机系统识别方法来识别紊流风场中的气动导数, 与当前应用较广的瞬态激励法及强迫激励法相比, 这类方法的优势在于: (1) 将紊流看作是激励, 而不是噪声, 更能反映结构实际工作状态下的特性; (2) 识别精度不受风速的制约, 可以获得较高折减风速下的气动导数; (3) 可直接在紊流风场中结构随机响应上进行识别, 无需任何人为外在激励, 试验更为简单易行。在风洞中完成了紊流风场中桥梁节段模型测振试验, 进一步利用本文的方法识别出气动导数。与相关文献提供的类似模型在均匀场和紊流场中识别结果的对比表明: 本文识别的气动导数是可靠的, 所提出的采用随机系统识别方法来识别紊流风场中气动导数的思路是可行的。

关键词：气动导数模态参数识别随机子空间方法风致振动桥梁结构