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Linear Electron-Phonon Interaction in Organic Spectral Hole-Burning Materials

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Chinese Physics Letters 1993年第10期10卷 634-637页

作者： tian mingzhen LUO Baozhu LI Wenlian HUANG Shihua YU Jiaqi YANG Kaihai Cliangchun Institu te of Physics AcademiaSinicaChangchun 130021 Rese&rch Center Liaoning Normal UniversityDalian 116022

The linear electron-phonon interaction in polymethylmethacrylate(PMMA)doped with electron donor zinc-tetraphenylbenzoporphyrin(ZnTPBP)and acceptor p-hydroxybenzsAdhyde(PHBA)t or p-aininoacetophenone(PAAP)was investigated by photon-gated spectral hole-burning(PHB),The aim is to study the factors that&ffed the linear elec iron-ph on on coupling and the thermal stability of spectral holes in the organic film samples.

关键词： spectral Electron donor

Detecting and monitoring of water inrush in tunnels and coal mines using direct current resistivity method:A review

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第4期7卷 469-478页

作者： Shucai Li Bin Liu Lichao Nie Zhengyu Liu mingzhen tian Shirui Wang Maoxin Su Qian Guo Geotechnical and Structural Engineering Research Center Shandong University

Detecting, real-time monitoring and early warning of underground water-bearing structures are critically important issues in prevention and mitigation of water inrush hazards in underground engineering. Direct current （DC） resistivity method is a widely used method for routine detection, advanced detection and real-time monitoring of water-bearing structures, due to its high sensitivity to groundwater. In this study, the DC resistivity method applied to underground engineering is reviewed and discussed, including the observation mode, multiple inversions, and real-time monitoring. It is shown that a priori information constrained inversion is desirable to reduce the non-uniqueness of inversion, with which the accuracy of detection can be significantly improved. The focused resistivity method is prospective for advanced detection;with this method, the flanking interference can be reduced and the detection dis-tance is increased subsequently. The time-lapse resistivity inversion method is suitable for the regions with continuous conductivity changes, and it can be used to monitor water inrush in those regions. Based on above-mentioned features of various methods in terms of benefits and limitations, we propose a three-dimensional （3D） induced polarization method characterized with multi-electrode array, and introduce it into tunnels and mines combining with real-time monitoring with time-lapse inversion and cross-hole resistivity method. At last, the prospective applications of DC resistivity method are discussed as follows：（1） available advanced detection technology and instrument in tunnel excavated by tunnel boring machine （TBM）, （2） high-resolution detection method in holes, （3） four-dimensional （4D） monitoring technology for water inrush sources, and （4） estimation of water volume in water-bearing structures.

关键词： Direct current (DC) resistivity methodTechnical statusLatest progressUnderground engineeringWater inrushRoutine detectionAdvanced detectionReal-time monitoring

“Slope-adsorption&plateau-pore filling”mechanism unlocking the potential of hard carbon anodes for“fast-charging&large-sized”batteries

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Science China Materials 2025年第1期68卷 309-311页

作者： tian Liang Xiaoming Zhu Hubei Key Laboratory of Radiation Chemistry and Functional Materials School of Nuclear Technology and Chemistry&BiologyHubei University of Science and TechnologyXianning 437100China

To date,there has been no report on fast-charging and Ahlevel sodium-ion batteries(SIBs)by utilizing thick hard carbon anodes that demonstrate prolonged cycling life and high areal capacity at high ***,the relationship among the complex structure of hard carbon,storage mechanism,and fastcharging performance in alkali-metal ion batteries has been a subject of ongoing debate[1,2].

关键词： mechanism charging utilizing

New progresses of fine-grained sediment gravity-flow deposits and their importance for unconventional shale oil and gas plays

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Petroleum Science 2025年第1期22卷 1-15页

作者： tian Yang Ying-Lin Liu State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Chengdu University of Technology) Institute of Sedimentary Geology Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of Technology

Fine-grained sediments are widely distributed and constitute the most abundant component in sedimentary systems, thus the research on their genesis and distribution is of great significance. In recent years, fine-grained sediment gravity-flows(FGSGF) have been recognized as an important transportation and depositional mechanism for accumulating thick successions of fine-grained sediments. Through a comprehensive review and synthesis of global research on FGSGF deposition, the characteristics,depositional mechanisms, and distribution patterns of fine-grained sediment gravity-flow deposits(FGSGFD) are discussed, and future research prospects are clarified. In addition to the traditionally recognized low-density turbidity current and muddy debris flow, wave-enhanced gravity flow, lowdensity muddy hyperpycnal flow, and hypopycnal plumes can all form widely distributed FGSGFD. At the same time, the evolution of FGSGF during transportation can result in transitional and hybrid gravityflow deposits. The combination of multiple triggering mechanisms promotes the widespread development of FGSGFD, without temporal and spatial limitations. Different types and concentrations of clay minerals, organic matters, and organo-clay complexes are the keys to controlling the flow transformation of FGSGF from low-concentration turbidity currents to high-concentration muddy debris flows. Further study is needed on the interaction mechanism of FGSGF caused by different initiations, the evolution of FGSGF with the effect of organic-inorganic synergy, and the controlling factors of the distribution patterns of FGSGFD. The study of FGSGFD can shed some new light on the formation of widely developed thin-bedded siltstones within shales. At the same time, these insights may broaden the exploration scope of shale oil and gas, which have important geological significances for unconventional shale oil and gas.

关键词： Fine-grained sediment gravity-flow Depositional mechanism Transportation and evolution Distribution pattern Shale oil and gas

Upper Bounds on the Multicolor Ramsey Numbers r_(k)(C_(4))

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 286-294页

作者： tian-yu LI Qi-zhong LIN Center for Discrete Mathematics Fuzhou UniversityFuzhou 350108China

The multicolor Ramsey number r_(k)(C_(4))is the smallest integer N such that any k-edge coloring of KN contains a monochromatic C_(4).The current best upper bound of r_(k)(C_(4))was obtained by Chung(1974)and independently by Irving(1974),i.e.,r_(k)(C_(4))≤k^(2)+k+1 for all k≥*** is no progress on the upper bound since *** this paper,we improve the upper bound of r_(k)(C_(4))by showing that r_(k)(C_(4))≤k^(2)+k-1 for even k≥*** improvement is based on the upper bound of the Turan number ex(n,C4),in which we mainly use the double counting method and many novel ideas from Firke,Kosek,Nash,and Williford[***,Ser.B 103(2013),327-336].

关键词： Multicolor Ramsey number Turan number 4-cycle

Revisit the Gibbs-Thomson Equation Fitting of Poly(butylene succinate) Based on Oligomer Extended-Chain Crystals

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CHINESE JOURNAL OF POLYMER SCIENCE 2025年第2期43卷 392-398页

作者： Li, Na tian, Yu-Pei Wu, tian-Yu Zhou, Qiong Ye, Hai-Mu China Univ Petr Coll New Energy & Mat Beijing 102249 Peoples R China

The equilibrium melting point (Tm0) is a crucial thermodynamic parameter for characterizing the crystallization and melting behavior of semi-crystalline polymers. However, the direct measurement of Tm0 poses a significant challenge because of the difficulty in physically fabricating fully-extended chain crystals of high-molecular-weight polymers. Therefore, various extrapolation equations for Tm0 have been proposed that utilize the thermal properties of ordinary folded-chain lamellae. Among these, the Gibbs-Thomson equation is one of the most commonly employed for modeling. Despite its widespread use, there are notable variations in the Tm0 values obtained by different research groups, even when based on similar samples. This raises questions about the validity and accuracy of using the Gibbs-Thomson equation to linearly extrapolate Tm0. In this study, we prepared a series of oligomer extended-chain crystals (ECCs) of poly(butylene succinate) (PBS) and used their properties for Gibbs-Thomson fitting. The results reveal a perfect linear relationship, with an extrapolated Tm0 value of 136.08 degrees C. The basal surface free energy of the oligomer ECCs was calculated as 0.084 J/m2, which is approximately twice that of folded-chain lamellae. This difference is attributed to the aggregation of highly mobile free tails on the crystal surface. The two structural features of oligomer ECCs-large thickness and fixed surface-better fulfill the conditions for applying the Gibbs-Thomson equation, ensuring its validity and accuracy. Therefore, we believe that the Gibbs-Thomson fit can produce reliable results when sufficient high-quality data are used.

关键词： Equilibrium melting point Extended-chain crystal Gibbs-Thomson equation Inclusion complex

Synthesis of ternary geopolymers using prediction for effective solidification of mercury in tailings

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Journal of Environmental Sciences 2025年第1期147卷 392-403页

作者： Xuan Lu Jinfa Guo Fang Chen Mengkui tian School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China

This study used steel slag,fly ash,and metakaolin as raw materials(SFM materials)to create silica-alumina-based geopolymers that can solidify Hg^(2+)when activated with sodiumbased water *** experiments began with a triangular lattice point mixing design experiment,and the results were fitted,analyzed,and *** optimum SFM material mass ratio was found to be 70%steel slag,25%fly ash,and 5%*** optimum modulus of the activator was identified by comparing the unconfined compressive strength and solidifying impact on Hg^(2+)of geosynthetics with different *** SFM geopolymer was then applied in the form of potting to cure the granulated mercury *** inclusion of 50%SFM material generated a geosynthetic that reduced mercury transport to the surface soil by roughly 90%.The mercury concentration of herbaceous plant samples was also reduced by 78%.It indicates that the SFM material can effectively attenuate the migration transformation of ***,characterization methods such as XPS and FTIR were used to investigate the mechanism of Hg^(2+)solidification by geopolymers generated by SFM *** possible solidification mechanisms were proposed as alkaline environment-induced mercury precipitation,chemical bonding s,surface adsorption of Hg^(2+)and its precipitates by the geopolymer,and physical encapsulation.

关键词： Mercury Geopolymer Solidification Tailings

Acupuncture Combined with Periocular Injection for Treatment of Hydroxychloroquine Retinopathy with Cystoid Macular Edema:A Case Report

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Chinese Journal of Integrative Medicine 2025年第1期31卷 68-72页

作者： LI tian-tian WU Yan YANG Ying-xin XUE Yu-xin MA Chao-ting Department of Ophthalmology Beijing Hospital of Traditional Chinese MedicineCapital Medical UniversityBeijing100010China

Hydroxychloroquine(HCQ)is widely used in the treatment of autoimmune disorders such as systemic lupus erythematosus(SLE)and rheumatoid arthritis,and in recent years it has also been used in diseases such as cancer,neurodegenerative diseases,metabolic diseases,and microbial infections.(1)Due to the complex pharmacokinetic characteristics of HCQ,overdose or long-term use of the drug will lead to accumulation in the tissue of organism,and severe HCQ-related retinal toxicity may occur.A cohort study in America showes that after 10 and 15 years of HCQ use,the incidence of HCQ retinopathy will be 2.5%and 8.6%,respectively.(2)The clinical manifestations of HCQ retinopathy are various,mainly photoreceptor and retinal pigment epithelium(RPE)defects,some combined with cystoid macular edema(CME),and ireversible central vision loss.

关键词： Acupuncture diseases epithelium

Benchmarking model chemistry composite calculations for vertical ionization potential of molecular systems

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Chinese Chemical Letters 2025年第02期36卷 536-539页

作者： Bingwei Wang Yihong Ding Xiao tian Key Laboratory of Carbon Materials of Zhejiang Province Wenzhou Key Lab of Advanced Energy Storage and Conversion Zhejiang Province Key Lab of Leather Engineering College of Chemistry and Materials Engineering Wenzhou University Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University School of Mathematics and Science Hebei GEO University

In chemical science, the vertical ionization potential(VIP) is a crucial metric for understanding the electronegativity, hardness and softness of chemical material systems as well as the electronic structure and stability of molecules. Ever since the last century, the model chemistry composite methods have witnessed tremendous developments in computing the thermodynamic properties as well as the barrier heights. However, their performance in realm of the vertical electron processes of molecular systems has been rarely explored. In this study, we for the first time benchmarked the model chemistry composite methods(e.g., CBS-QB3, G4 and W1BD) in comparison with the commonly used Koopmans' s theorem(KT), electron propagator theory(e.g., OVGF, D2, P3 and P3+) and CCSD(T) methods in calculating the VIP for up to 613 molecular systems with available experimental measurements. The large-scale test calculations strongly showed that the CBS-QB3 model chemistry composite technique can be well recommended to calculate VIP from the perspectives of accuracy, economy and applicability. Notably, the VIP values of up to 7 molecules were identified to have the absolute errors of larger than 0.3 e V at all calculation levels,which have strong hints that their VIP experimental values should be re-investigated.

关键词： CBS-QB3 Composite methods Model chemistry Molecular systems Vertical ionization potential