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Collapse analysis of tunnel floor in karst area based on Hoek-Brown rock media

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Journal of Central South University 2017年第4期24卷 957-966页

作者： YANG xiao-li LI Zheng-wei LIU Zheng-an xiao hai-bo School of Civil Engineering Central South University Changsha 410075 China

Collapse shape of tunnel floor in Hoek-Brown rock media is investigated with the functional catastrophe theory. The stability of rock system in tunnel floor, which is determined by thickness, half collapse width, half length of cave and detaching curve, has great secure and economic significance in practical engineering. To investigate the failure mechanisms and the outline of detaching block, a reliable damage model is presumed by making reference to the limit analysis theory. The analytical solutions of detaching curve, half collapse width on tunnel floor and the critical and maximum values of collapse thickness are derived based on Hoek-Brown criterion and functional catastrophe theory. The result shows that 0.5 is a most probable condition for instability, and the shape of detaching curve is a part of parabola. It is reasonable by comparing with previous theory and analogous experiments. The effects of major factors on thickness and half collapse width are further discussed. Numerical calculations and parametric analysis are carried out to illustrate the effects of different parameters on the mechanism, which is significant to the stability analysis of tunnel floor in rock media.

关键词： karst functional catastrophe theory Hoek-Brown criterion safety thickness tunnel floor upper bound

A novel soluble polyamide containing xanthene structure and trifluoromethylphenoxy pendent

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Chinese Chemical Letters 2010年第2期21卷 242-244页

作者： Huang, Zhen Zhong Wan, Xue Mei xiao, hai bo Sheng, Shou Ri Song, Cai Sheng Jiangxi Normal Univ Coll Chem & Chem Engn Nanchang 330022 Peoples R China

A novel polyamide containing xanthene structure and trifluoromethylphenoxy pendent was prepared from 9,9-bis[4-(4- aminophenoxy)phenyl]xanthene,a novel diamine with 2-(4-trifluoromethylphenoxy)terephthaloyl chloride,by the low temperature *** new polyamide with the inherent viscosity of 0.95 dL/g was amorphous and readily soluble in polar solvents such as DMAc,m-cresol,*** polyamide showed the glass transition temperature(T_g) of 236℃,decomposition temperature (Td) at 5%weight loss of...

关键词： Polyamide Xanthene cardo group:Trifluoromethylphenoxy pendent Soluble

转基因烟草表达西红花CSzCD基因产生西红花酸

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中国生物工程杂志 2007年第6期27卷 51-55页

作者：肖海波王岚严琛徐莺陈放唐琳四川大学生命科学学院成都610064

为研究转基因烟草中产生西红花酸的可行性,研究西红花玉米黄素裂解酶(CSzCD)基因插入到pBI121载体的花椰菜花病毒(CaMV)35S启动子下游,通过农杆菌介导整合到烟草基因组中。通过Southern blotting分析得到21株转基因烟草株系;对转基因烟... 详细信息

为研究转基因烟草中产生西红花酸的可行性,研究西红花玉米黄素裂解酶(CSzCD)基因插入到pBI121载体的花椰菜花病毒(CaMV)35S启动子下游,通过农杆菌介导整合到烟草基因组中。通过Southern blotting分析得到21株转基因烟草株系;对转基因烟草叶片提取物进行Western blotting分析和HPLC分析,结果显示有西红花酸的产生,阴性对照未发现西红花酸的存在。

关键词：西红花西红花酸西红花甙玉米黄素裂解酶转基因烟草

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铸态QT600-10材料的生产应用

铸造 2018年第8期67卷 732-736页

作者：肖海波东风精密铸造有限公司湖北十堰442714

通过对高强度高伸长率球墨铸铁金相组织结构及化学成分优化设计,选择Si、Cu为主要强化合金元素,采用覆膜砂壳型工艺生产铸态QT600-10球铁铸件。对铸态QT600-10材质试样的化学成分与力学性能进行了检测,并同步开展了替代铸钢产品试验。... 详细信息

通过对高强度高伸长率球墨铸铁金相组织结构及化学成分优化设计,选择Si、Cu为主要强化合金元素,采用覆膜砂壳型工艺生产铸态QT600-10球铁铸件。对铸态QT600-10材质试样的化学成分与力学性能进行了检测,并同步开展了替代铸钢产品试验。经生产验证,采用覆膜砂壳型工艺、合金强化以及控制好覆膜砂壳型铸后保温及溃散过程,能够稳定地生产铸态QT600-10球墨铸铁材料。

关键词：覆膜砂壳型工艺 QT600-10 铸态球墨铸铁

Potential dependence in electrocatalysis: a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu Liu Zhaoming Xia Zeyu Wang Yinjuan Chen hai xiao Department of Chemistry Tsinghua University Fundamental Science Center of Rare Earths Ganjiang Innovation Academy Chinese Academy of Sciences Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation Center Changzhou University

Electrocatalysis is a key technology for the new energy era and sustainable development, serving as the interface for interconversion of electrical and chemical energies, which spans a wide spectrum of applications in sustainable energy and environmental engineering. Electrocatalytic reactions including electrochemical CO2reduction reaction （eCO2RR）, hydrogen evolution reaction （HER）, and oxygen evolution/reduction reactions （OER/ORR）, hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

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Two-Photon Fluorescence Property and Ultrafast Dynamics of Two Dipolar Compounds with Dipicolinate as Electron Acceptor

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Chinese Physics Letters 2010年第3期27卷 300-303页

作者：王耀川周慧丁金亮陈强肖海波陶晓明钱士雄 Department of Physics Fudan University Shanghai 200433 Surface Physics Laboratory (State Key Laboratory) Fudan University Shanghai 200433 Department of Chemistry Shanghai Normal University Shanghai 200234

Linear and nonlinear photophysical properties of two novel dipolar compounds named as trans- dimethyl-4-[4＇-（N,N-dimethylamino）-styry1]-pyridin-2,6-dicarboxylate （xiao-1） and trans-dimethyl-4-[4＇-（N,N-diphenylamino）-styry1]-pyridin-2,6-dicarboxylate （xiao-2） are investigated by steady-state absorption and fluorescence spectroscopy, Z-scan and two-photon excited fluorescence measurements. Strong two-photon fluorescence emission and the pronounced positive solvatochromism are observed from two compounds. The two-photon absorption cross section of xiao-2 is about 1.5 times larger than that of xiao-1. One-color and two-color femtosecond pump-probe experiments are employed to investigate the excited state dynamics of two compounds. The relaxation lifetime of the intra-molecular charge transfer state is determined to be in the hundreds of picosecond domain for both the compounds in THF, and several tens of picosecond in DMSO solutions.

关键词： Soft matter liquids and polymers Condensed matter: electrical magnetic and optical

基于分布式信息流控制的无障碍辅助性服务安全加固

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软件学报 2018年第5期29卷 1318-1332页

作者：李晓娟陈海波上海交通大学并行与分布式系统研究所上海200240

随着安卓系统的广泛使用,系统提供的功能也越来越多,其中一个重要特性是1.6版本中引入并在4.0及以上版本中优化的无障碍辅助性服务.通过无障碍辅助功能,应用不仅可以获得输入框输入文本等窗口元素信息,还可以与应用窗口自动地进行双向交... 详细信息

随着安卓系统的广泛使用,系统提供的功能也越来越多,其中一个重要特性是1.6版本中引入并在4.0及以上版本中优化的无障碍辅助性服务.通过无障碍辅助功能,应用不仅可以获得输入框输入文本等窗口元素信息,还可以与应用窗口自动地进行双向交互(如获得按钮信息点击按钮).然而,这些特性一旦被滥用,将会给用户带来巨大的安全威胁.对安卓系统中的无障碍辅助性服务进行了深入研究,分析了其可能被滥用的途径,并找出安全缺陷及其产生原因.然后提出了基于分布式信息流的控制机制标记,并跟踪无障碍辅助性服务和无障碍事件以进行安全加固.实现了一个名为Tassel的安全系统,以防止无障碍辅助性服务滥用.经过测试,该系统可以在不影响系统其他功能正常使用的前提下,保证服务的使用安全,且系统整体的性能影响很小.

关键词：安卓系统无障碍辅助性服务系统漏洞与安全分布式信息流控制

A Spirobifluorene-based Two-photon Fluorescence Probe for Mercury Ions and Its Applications in Living Cells

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A Spirobifluorene-based Two-photon Fluorescence Probe for Me...

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

中国化学会第十三届全国有机合成化学学术研讨会

作者： xiao hai-bo Zhang Yan-Zhen Zhang Wu Li Shao-Zhi Department of Chemistry Shanghai Normal University

A novel spirobifluorene derivative SPF-TMS,which containing dithioacetal groups and triphenylamine units,was *** probing behaviors toward various metal ions were investigated via UV/Vis absorption spectra as well as one-photon fluorescence *** results indicated that SPF-TMS exhibits high sensitivity and selectivity for mercury *** detection limit was at least 8.6×10-8 M,which is excellent comparing with other optical sensors for Hg2+.When measured by two-photon excited fluorescence technique in THF at 800 nm,the two-photon cross-section of SPF-TMS is 272 ***,upon reaction with mercury species,SPF-TMS yielded another two-photon dye *** SPF-TMS and SPF-DA emit strong two-photon induced fluorescence and can be applied in cell imaging by two-photon microscopy.

关键词： two-photon fluorescence probe mercury ion Spirobifluorene

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang xiao-Li Zhao Lin Xu Linlin Liu xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng hai-bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction