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A potential NMR-based wettability index using free induction decay for rocks

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Magnetic Resonance Letters 2023年第3期3卷 266-275,I0004页

作者： can liang Zijian Jia Lizhi Xiao Guwen Wang Yan Mao Xiaopeng Ma Changzhou Institute of Technology Changzhou213032China University of Shanghai for Science and Technology Shanghai200093China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China

The wettability of reservoir rocks saturated with oil and water is one of the most important factors influencing petrophysics and oil *** with different wettability constitute the overall heterogeneous wettability in *** in sample composi-tion can be detected by nuclear magnetic resonance(NMR)*** this paper,the method of using the magnetic susceptibility contrast between rock skeleton and saturated fluid to estimate wettability is *** theoretical feasibility was firstly analyzed,and then the internal gradients caused by magnetic susceptibility contrasts were employed to interpret wettability alteration before and after ageing process in *** was discovered that water and oil in the same pores experienced different internal gradients after ageing,which were associated with the differences in magnetic susceptibility *** that,the free induction decay measurement was performed to acquire mag-netic susceptibility contrasts of artificial sandstone samples with the intermediate-wet condition.A refined NMR wettability index was presented and correlated with the Amott wettability *** experimental results demonstrate that the new method for deter-mining wettability is feasible.

关键词： NMR Wettability characterization Magnetic susceptibility contrast Internal gradients

Constructing mild expanded graphite microspheres by pressurized oxidation combined microwave treatment for enhanced lithium storage

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Rare Metals 2021年第4期40卷 837-847页

作者： can-liang Ma Zhen-Hui Hu Ning-Jing Song Yun Zhao Yan-Zhen Liu Hui-Qi Wang Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province Institute of Molecular ScienceShanxi UniversityTaiyuan 030006China College of Chemistry and Chemical Engineering Jinzhong UniversityJinzhong 030619China CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China School of Energy and Power Engineering School of Material Science and EngineeringNorth University of ChinaTaiyuan 030051China

The modified graphite anode materials have some prominent advantages over other anode materials in the industrial applications.A novel simple and gentle method is proposed to synthesize the mild expanded graphite microspheres(MEGMs) from flake graphite spheres through a combined modified pressurized oxidation combined with the microwave *** microstructural results demonstrate that moderately expanded MEGMs with an expansion volume between 4 and 10 ml·g^(-1)exhibit a highly microporous structure with an enlarged interlayer spacing,a decreased microcrystalline size,as well as an increased number of functional groups on the surface,resulting in the increased storage sites and spaces for lithium ions and the enhanced diffusion rate of lithium *** used as the anode material for lithium-ion batteries,the MEGM-T75t30 obtained by oxidation treatment at 75℃ for 30 min followed by microwave irradiation for expansion displays a high reversible capacity of 446.7 mAh·g^(-1) at 100 mA·g^(-1) after 100 cycles and excellent rate performance(330 and 116 mAh·g^(-1) at 800 and 3200 mA·g^(-1),respectively).Therefore,the MEGMs prepared by this convenient and mild method show excellent electrochemical properties and good application potential.

关键词： Pressurized oxidation Microwave treatment Mild expanded graphite microspheres Microstructure Graphitic anode material Lithium-ion battery

A machine learning framework for low-field NMR data processing

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Petroleum Science 2022年第2期19卷 581-593页

作者： Si-Hui Luo Li-Zhi Xiao Yan Jin Guang-Zhi Liao Bin-Sen Xu Jun Zhou can liang College of Artificial Intelligence and College of Petroleum Engineering China University of PetroleumBeijing102249China China National Logging Corporation Xi©anShaanxi 710076China Changzhou Institute of Technology ChangzhouJiangsu213000China

Low-field(nuclear magnetic resonance)NMR has been widely used in petroleum industry,such as well logging and laboratory rock core ***,the signal-to-noise ratio is low due to the low magnetic field strength of NMR tools and the complex petrophysical properties of detected *** the noise and highlighting the available NMR signals is very important for subsequent data *** denoising methods are normally based on fixed mathematical transformation or handdesign feature selectors to suppress noise characteristics,which may not perform well because of their non-adaptive performance to different noisy *** this paper,we proposed a“data processing framework”to improve the quality of low field NMR echo data based on dictionary *** learning is a machine learning method based on redundancy and sparse representation *** information in noisy NMR echo data can be adaptively extracted and reconstructed by dictionary *** advantages and application effectiveness of the proposed method were verified with a number of numerical simulations,NMR core data analyses,and NMR logging data *** results show that dictionary learning can significantly improve the quality of NMR echo data with high noise level and effectively improve the accuracy and reliability of inversion results.

关键词： Dictionary learning Low-field NMR Denoising Data processing T_(2)distribution

Low-field NMR inversion based on low-rank and sparsity restraint of relaxation spectra

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Petroleum Science 2022年第6期19卷 2741-2756页

作者： Si-Hui Luo Li-Zhi Xiao Yan Jin Jiang-Feng Guo Xiao-Bo Qu Zhang-Ren Tu Gang Luo can liang College of Artificial Intelligence and College of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China School of Electronic Science and Engineering(National Model Microelectronics College) Xiamen UniversityFujian361005China School of Electronic Science and Engineering National Model Microelectronics College Xiamen University Changzhou Institute of Technology ChangzhouJiangsu213000China

In this paper,we proposed a novel method for low-field nuclear magnetic resonance(NMR)inversion based on low-rank and sparsity restraint(LRSR)of relaxation spectra,with which high quality construction is made possible for one-and two-dimensional low-field and low signal to noise ratio NMR *** this method,the low-rank and sparsity restraints are introduced into the objective function instead of the smoothing *** low-rank features in relaxation spectra are extracted to ensure the local characteristics and morphology of *** sparsity and residual term are contributed to the resolution and precision of spectra,with the elimination of the redundant relaxation *** process of the objective function is designed with alternating direction method of multiples,in which the objective function is decomposed into three subproblems to be independently *** optimum solution can be obtained by alternating iteration and updating *** first,numerical simulations are conducted on synthetic echo data with different signal-to-noise ratios,to optimize the desirable regularization parameters and verify the feasibility and effectiveness of proposed ***,NMR experiments on solutions and artificial sandstone samples are conducted and analyzed,which validates the robustness and reliability of the proposed *** results from simulations and experiments have demonstrated that the suggested method has unique advantages for improving the resolution of relaxation spectra and enhancing the ability of fluid quantitative identification.

关键词： Low-field NMR Inversion method Low-rank and sparsity restraint Relaxation spectra Data processing

Synthesis and Study of Second-order Nonlinear Optical Properties of 3-Substituted-6- (substituted-phenylazo) coumarins

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有机化学 2003年第Z1期23卷 411-412页

作者： SONG Hua-can WEN Huan liang Dong SUN Yi-Feng School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275 School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275 School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275 School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275

　　It has attracted a lot of attentions to synthesize and investigate the behaviors of organic second-order nonlinear optical (NLO) materials. [1,2] We have ever reported that acridine derivatives ,[3] 4-substituted-benzylideneoxazol-5(4H)-one[4] and 4,4′-di-styryl-biphenyl derivatives[5] possess good second-order NLO properties. Coumarin derivatives are good organic optical materials and azobenzene derivatives possess a higher second-order nonlinear polarization values, however, there are few reports about the study on the synthetic method, optical behavior, especially,second-order NLO properties of 3-substitued-6-(substituted-phenylazo) coumarin derivatives. Therefore, a series of the following compounds were prepared in order to investigate their NLO behavior.……

关键词： optical materials nonlinear optical synthetic method in order

Synthesis and Study of Two-photon Absorption Behavior of 3- (3-Arylacryloyl) -chromen-2-one Derivatives

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有机化学 2003年第Z1期23卷 409-410页

作者： SONG Hua-can liang Hui-Fen SUN Yi-Feng YAO Jun-Hua School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275 School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275 School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275 School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275

　　The study on two-photon absorption materials has attracted a lot of attention in recent years, many good re search results have been obtained in the field of two-photon fluorescent microscopy and imaging. [ 1 ～ 4] It was found in our laboratory that some 3-(3-arylacryloyl)-chromen-2-one derivatives possess good two-photon absorption behav-ior, [5] therefore, a series of this family of compounds was synthesized.……

关键词： fluorescent microscopy

Zwitterionic ring-opening polymerization of macrocyclic ethyleneoxy-substituted carbonate:Access to cyclic PEG-like polycarbonate

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Chinese Chemical Letters 2024年第3期35卷 282-286页

作者： Jin Huang Jinwen Li Rui Yan Yuanyuan Qu Fengzhen Guo Lei Shen can-liang Ma Jie Sun Zhenjiang Li Kai Guo State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China Institute of Nanjing Advanced Biomaterials&Processing Equipment Lishui Economic Development ZoneNanjing 211299China

The innovation in polymer design to rival conventional polyethylene glycol(PEG)is an important approach to achieving a more sustainable ***,cyclic PEG-like polycarbonates having high molecular weight(4.4–49.5 kg/mol)were enabled through zwitterionic ring-opening polymerization(ZROP)of macrocyclic carbonates(MCs)mediated by N-heterocyclic carbene(NHC).The thermodynamic behavior of polymerization depends on the ring size of *** this process,the ZROP of 11-membered MC was driven by the change of enthalpy(ΔH_(p))which differed from the ZROP of 14-membered MC driven by the entropic change(ΔS_(p)).Cyclic polycarbonates depicted improved thermostability(T_(d5%)≥204℃)and higher glass transition temperatures(T_(g)>–40℃)in comparison to their linear analogues(T_(d5%)≤185℃,T_(g)~–50℃).In addition,the mechanism of ZROP of MC was addressed through computational study.A distinct mechanism of polymerization distinguishable from the well-known NHC-mediated ZROP of cyclic esters was revealed,where the zwitterion from nucleophilic addition to MC,*** intermediate,cannot be ring-opened probably due to the delocalization of negative charge on the carbonate group,but serves as an active center for the *** comparison to PEG,the attained polymer demonstrated comparable hydrophilic and biocompatible properties,as revealed by the results of contact angle and in vitro cytotoxicity studies,suggesting that cyclic polycarbonate hold the promise as the alternative of PEG.

关键词： Zwitterionic ring-opening polymerization Cyclic polycarbonate Macrocycles Tetrahedral intermediate NHC carbene

论审美体验的非时间性——以米歇尔·亨利对时间性概念的批判为线索

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文艺理论研究 2020年第4期40卷 52-58页

作者：梁灿东莞理工学院马克思主义学院 523808

时间性通常被认为是审美体验显现自身的先验条件。亨利通过严格区分事物的两种显现方式,对此提出了挑战。亨利认为,时间性的本质是虚无,无法给予事物任何实在。如果强行把时间性结构置于审美体验之中,只会使之失去活生生的实在。审美体... 详细信息

时间性通常被认为是审美体验显现自身的先验条件。亨利通过严格区分事物的两种显现方式,对此提出了挑战。亨利认为,时间性的本质是虚无,无法给予事物任何实在。如果强行把时间性结构置于审美体验之中,只会使之失去活生生的实在。审美体验就是生命的一种形态,它构成了生命自我转化和自我生长的一个重要环节。只有在生命的自我感受中,审美体验才能如其所是地显现自身。

关键词：米歇尔·亨利审美体验时间性生命

Calculating and analyzing ecological footprints of Guangxi Zhuang Autonomous Region in 2017

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Ecological Economy 2019年第2期12卷 82-87页

作者： LIU liang-can YAO Nan Guizhou University of Finance and Economics

In order to analyze the sustainable development of Guangxi Zhuang Autonomous Region, this paper analyzed the development of Guangxi Zhuang Autonomous Region in 2017 by using ecological footprint method. The results showed that the ecological footprint per capita in Guangxi Zhuang Autonomous Region was 3.9056 hm^2 in 2017, the ecological carrying capacity per capita was 1.0932 hm^2, the ecological ecology was 2.8125 hm^2 and the ecological footprint intensity index was 3.5728. Based on the ecological footprint, the diversity index was 0.9126. Based on the ecological footprint, the social development index was 3.5643. Based on ecological carrying capacity, the diversity index was 1.0612. Based on ecological carrying capacity, the social development index was 1.1601. It shows that the production and living intensity of the Guangxi Zhuang Autonomous Region exceed the carrying capacity of the ecological system, and it is in the unsustainable development level according to the level of sustainable development in China.

关键词： ecological footprint ecological carrying capacity ecological footprint diversity sustainable development