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Experimental and Theoretical Investigations of Solvent Polarity Effect on ESIPT Mechanism in 4′-N,N-diethylamino-3-hydroxybenzoflavone

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Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica 2025年第2期41.0卷 116-124页

作者： Jiang, Yanglin Chen, Mingqing Liang, Min Yao, Yige zhang, Yan Wang, Peng zhang, jianping Key Laboratory of Advanced Light Conversion Materials and Biophotonics Department of Chemistry Renmin University of China Beijing 100872 China Information Technology Center Renmin University of China Beijing 100872 China State Key Laboratory for Artificial Microstructure and Mesoscopic Physics School of Physics Peking University Beijing 100871 China State Key Laboratory of Elemento-organic Chemistry College of Chemistry Nankai University Tianjin 300071 China

Excited-state intramolecular proton transfer (ESIPT) is a fundamental photoreaction of significant importance in both chemical and biological systems. This phenomenon typically occurs in chromophores featuring intramolecular hydrogen bonding. Among the molecules undergoing ESIPT, 3-hydroxyflavone derivatives (3-HFs) have garnered significant attention due to their natural origins and environmentally responsive fluorescence properties. A particular 3-HF compound, 4′-N,N-diethylamino-3-hydroxybenzoflavone (D-HBF), distinguished by its extended π-system and red-shifted electronic absorption, has recently been identified as a potent fluorescent probe highly sensitive to changes in environmental polarity. In this study, we systematically explored the ESIPT reaction mechanism of D-HBF in three aprotic solvents: cyclohexane, diethyl ether, and tetrahydrofuran, each possessing varying polarities. Our investigation involved a combination of spectroscopic and theoretical methods. In all three solvents, we observed the characteristic dual emission bands associated with ESIPT, with the intensity ratio of these bands being influenced by the solvent. As solvent polarity increased, we noted a decrease in the rates of both the forward and reverse proton transfer (PT) reactions based on our analysis of fluorescent kinetics. However, the reverse PT was favored. Through density functional theory (DFT) and time-dependent DFT (TDDFT) calculations of bond lengths and bond angles of the intramolecular hydrogen bond in these solvents, we confirmed that the ESIPT reaction in D-HBF is driven by the strengthening of the excited-state hydrogen bond. Notably, upon increasing solvent polarity, the intramolecular hydrogen bonds in the excited N* state weakened, as evidenced by the up-shifted IR absorption frequency of the O―H stretching mode in the S1 state. Electron intensity analysis of frontier orbitals revealed characteristic intramolecular charge transfer (ICT) occurring in D-HBF upon photoe

关键词： 4′-N,N-diethylamino-3-hydroxybenzoflavone DFT/TD-DFT ESIPT Fluorescent dynamics Solvent polarity effect

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Cognitive malingering assessed using event-related potential P300 evoked by the old-new task in the oddball paradigm

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Neural Regeneration Research 2011年第12期6卷 946-950页

作者： jianping zhang Zhenhe Zhou Department of Neurology Wuxi People's Hospital Wuxi 214000 Jiangsu Province China Department of Psychology Wuxi Mental Health Center Wuxi 214151 Jiangsu Province China

The P300, an endogenous subcomponent of the event-related potential, is thought to reflect cognitive processes. The event-related potential evoked by the old-new memory recognition task in the oddball paradigm is suitable for examining the neural processes involved in malingered neurocognitive deficits. Forty-four undergraduates were randomly assigned to a simulated malingering group and a truth-telling group, Another 22 patients with head injudes were enrolled as a control group. All participants completed the old-new memory recognition task in the oddball paradigm. The mean P300 amplitude of the simulated malingering group was significantly reduced compared with the truth-telling group （P 〈 0.01）, but was increased compared with the control group （P〈 0.01）. These results revealed that the P300, evoked by the old-new memory recognition task of the oddball paradigm, may be a helpful indicator for determining cognitive malingering.

关键词： event-related potentials old-new memory recognition task malingered neurocognitive deficit oddball paradigm

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MULTI-FIELD COUPLING BEHAVIOR OF SIMPLY-SUPPORTED CONDUCTIVE PLATE UNDER THE CONDITION OF A TRANSVERSE STRONG IMPULSIVE MAGNETIC FIELD

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Acta Mechanica Solida Sinica 2006年第3期19卷 203-211页

作者： Zhu Linli zhang jianping Zheng Xiaojing Department of Mechanics and Engineering Science Lanzhou University Lanzhou 730000 China

In order to study the multi-field coupling mechanical behavior of the simply-supported conductive rectangular thin plate under the condition of an externally lateral strong impulsive magnetic field, that is the dynamic buckling phenomenon of the thin plates in the effect of the magnetic volume forces produced by the interaction between the eddy current and the magnetic fields, a FEM analysis program is developed to characterize the phenomena of magnetoelastic buckling and instability of the plates. The critical values of magnetic field for the three different initial vibrating modes are obtained, with a detailed discussion made on the effects of the lengththickness ratio a/h of the plate and the length-width ratio a/b as well as the impulse parameter on the critical value BOcr of the applied magnetic field.

关键词： multi-field coupling conductive thin plate impulsive magnetic field eddy current dynamic buckling magnetic volume forces

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Study of methods for evaluating the probability of multiple site damage occurrences

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Science China(Physics,Mechanics & Astronomy) 2014年第1期57卷 65-73页

作者： zhang jianping zhang JianYu BAO Rui ZHENG XiaoLing Institute of Solid Mechanics Beihang University Beijing Aeronautical Science & Technology research Institute

Two methods currently available for evaluating the probability of Multiple Site Damage(MSD)occurrence were studied in this *** of the methods is a probabilistic analysis approach based on the statistical theory and fatigue characteristics of each structural detail,and the other is an approach which defines the initial damage scenario by means of Monte-Carlo simulation,and multiple initial crack scenarios are randomly generated.A modified method based on the Monte-Carlo simulation was proposed in this paper,in which the random fluctuation of the stress was considered to give more accurate evaluation *** the presented method,the probability of MSD occurrence in a structural element containing multiple details was calculated based on the Monte-Carlo simulation and the p-S-N curve of a single structural *** tests were accomplished using specimens containing 21-similar-details to obtain the fatigue life corresponding to MSD *** on single-detail specimens and static calibration tests were also conducted to get the basic fatigue properties of the material and the degree of stress *** aforementioned three methods were compared and validated via the test *** influence of the stress random fluctuation degree on the probability of MSD occurrence and influence of the distribution types on evaluating the MSD occurrence probability were discussed.

关键词： Multiple Site Damage (MSD) fatigue crack initiation probability stress fluctuation

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深度翻译策略在中华学术外译项目中的应用

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武夷学院学报 2025年第1期44卷 75-82页

作者：张建平徐子懿江西理工大学外国语学院江西赣州341000

以国家社科基金中华学术外译项目《中国特色解决民族问题之路》为研究对象,该项目系统回顾了中国共产党认识和解决民族问题的艰难历程,聚焦中华民族共同体故事的对外译介和国际传播。该外译成果于2020年在国际上享有盛名的斯普林格出版... 详细信息

以国家社科基金中华学术外译项目《中国特色解决民族问题之路》为研究对象,该项目系统回顾了中国共产党认识和解决民族问题的艰难历程,聚焦中华民族共同体故事的对外译介和国际传播。该外译成果于2020年在国际上享有盛名的斯普林格出版集团推出后,进入了国外主流发行传播渠道,大力促进在西方主流话语结构中讲好中华民族共同体故事。在深度翻译理论框架下,探究了深度翻译策略在该学术外译项目中的具体应用:其一是显性深度翻译,指用“加注”的方式将文本置于深厚语言文化背景中;其二为隐性深度翻译,指将必要的解释说明“嵌入”译文正文之中。结果显示:深度翻译策略在该外译项目的合理应用有利于向英语读者阐释中国民族理论和政策,凸显共性议题和共性价值,阐幽抉微,出乎其外,有效提升中国学术和中国文化的国际影响力。

关键词：中华学术外译项目《中国特色民族解决之路》显性深度翻译加注隐性深度翻译策略嵌入

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Re- Thinking Classic Marxist Writers＇ Explications on Nationalism： on the ＂Difficult Dialogue between Marxism and Nationalism＂

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学术界 2015年第5期 257-263页

作者： zhang Sannan zhang jianping College of Humanites and Law Yanshan University Qinhuangdao Hebei 066004 Faculty of Foreign Studies Jiangxi University of Science and Technology Ganzhou Jiangxi 341000

Both Marxism and nationalism are among the most far-reaching thoughts in modern *** dealing the ideological collision between Marxism and nationalism, "Difficult Dialogue" universally exists in the academic *** scholars evaded,ridiculed or even negated classic Marxist writers' explications on *** basically,classic Marxist writers criticize nationalism,it doesn' t mean that Marxism and nationalism inevitably oppose to each *** is highly necessary to analyze the causes of the "difficult dialogue between Marxism and nationalism" and re-thinking classic Marxist writers' explications on nationalism.

关键词：马克思主义民族主义作家对话吃茶学术界

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Frequency-constrained Co-planning of Generation and Energy Storage with High-penetration Renewable Energy

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Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 760-775页

作者： Chengming zhang Lu Liu Haozhong Cheng Dundun Liu jianping zhang Gang Li Key Laboratory of Control of Power Transmission and Conversion Shanghai Jiao Tong UniversityShanghaiChina East China Branch of State Grid Corporation ShanghaiChina

Large-scale renewable energy integration decreases the system inertia and restricts frequency regulation. To maintain the frequency stability, allocating adequate frequency-support sources poses a critical challenge to planners. In this context, we propose a frequency-constrained coordination planning model of thermal units, wind farms, and battery energy storage systems (BESSs) to provide satisfactory frequency supports. Firstly, a modified multi-machine system frequency response (MSFR) model that accounts for the dynamic responses from both synchronous generators and grid-connected inverters is constructed with preset power-headroom. Secondly, the rate-of-change-of-frequency (ROCOF) and frequency response power are deduced to construct frequency constraints. A data-driven piecewise linearization (DDPWL) method based on hyperplane fitting and data classification is applied to linearize the highly nonlinear frequency response power. Thirdly, frequency constraints are inserted into our planning model, while the unit commitment based on the coordinated operation of the thermal-hydro-wind-BESS hybrid system is implemented. At last, the proposed model is applied to the IEEE RTS-79 test system. The results demonstrate the effectiveness of our co-planning model to keep the frequency stability.

关键词： Battery energy storage system(BESS) data-driven piecewise linearization generation planning multi-machine system frequency response unit commitment wind farm

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Discussion on marine source rocks thermal evolvement patterns in the Tarim Basin and Sichuan Basin,west China

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Chinese Science Bulletin 2007年第A01期52卷 141-149页

作者： zhang Bin ZHAO Zhe zhang ShuiChang CHEN jianping Central Laboratory of Petroleum Geology Research Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

Taking marine source rocks of lower Paleozoic in the Tarim Basin and Paleozoic ones in the Sichuan Basin as examples, their sedimentation process could be classified into four styles: continuous subsidence with deep sedimentation in early stage, continuous subsidence with deep sedimentation in later stage, that deeply buried-uplift-shallowly buried, and that shallowly buried-uplift-deeply buried. Unlike that in East China, the marine source rocks evolvement patterns did not accord with sedimentation styles one by one in superimposed basins in west China. Taking local geothermal field into account, four types of source rock evolvement patterns were built: that evolved fast in early stage, evolved fast in middle stage, evolved continuously and evolved in multistage. Among them, the 1st pattern contributed little to the present industrial oil pools directly, but paleo-oil reservoirs and gases cracked from crude oils were main exploration targets. Although some gases were found in the 2nd pattern, the scale was not big enough. For the 3rd and 4th patterns, the hydrocarbon potential depended on organic matters maturity in early stage. For relatively low mature rocks, it was possible to generate some oils in later stage; otherwise the main products were gases. Paleo-oil reservoirs remained fairly well in the Sichuan Basin, and most source rocks underwent kerogen-oil-gas processes, which was useful reference to gas exploration in the Tarim Basin.

关键词：热图形海洋源岩石碳氢化合物

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Mathematical model of solidification for round CC billets

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Journal of University of Science and Technology Beijing 2005年第5期12卷 400-405页

作者： Yonglin Li Pei Zhao Guoguang Cheng Shengtao Qiu jianping zhang Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China National Engineering and Research Center for Continuous Casting Technology Central Iron and Steel Research Institute Beijing 100081 China Technology Center Ma＇anshan Iron ＆ Steel Co. Ltd Ma＇anshan 243000 China

A coupled mathematical model was established to simulate the whole solidification process of round billet continuous casting for wheel steel using piecewise linear functions of heat flux density in the mold, the secondary cooling zone and the with- drawing-straightening zone. The calculated results were consistent with the measured data showing that the model accords with the practice. The surface temperature and the solidified shell thickness of round billets are more strongly influenced by casting speed than by casting temperature. The holding zones have effect on surface temperature, which is more obvious for the 450 mm round billet. The relation between casting temperature/speed and solidification end is expressed as a linear function. The solidification end is located after straightening machine.

关键词： round billet surface temperature solidified shell thickness solidification end

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Surfactant Effects on the Permeability of Photosynthetic Membrane from Rhodobacter sphaeroides 2.4.1 Probed by Electrochromic Shift of Endogenous Carotenoids

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Chemical Research in Chinese Universities 2018年第6期34卷 989-994页

作者： ZHOU Xuan YU Jie WANG Peng zhang jianping Department of Chemistry Renmin University of China Beijing 100872 P. R. China

Four surfactants, sodium cholate（SC）, n-dodecyl-β-D-maltopyranoside（DDM）, lauryldimethylalnine oxide（LDAO） and Triton X-100（TX）, which are generally used in photosynthetic pigment-protein complexes preparation, were studied on their interaction with photosynthetic membrane from Rhodobacter sphaeroides 2.4.1 by elec- trochromic absorption band-shift of endogenous carotenoids and by vesicle size measurements as well. The surfactant critical micelle concentration（cmc） was found to be negatively correlated with the capability of enhancing the per-meability of photosynthetic membranes to proton, and more elaborated model of snrfactants interacting with membranes was obtained. The electrochromic absorption band-shill measurement might develop into a useful tool to evaluate the effects of surfactants on various membranes.

关键词： Surfactant Photosynthetic membrane Electrochromic effect Carotenoid Permeability

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