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The new multistage water adsorption model of Longmaxi Formation shale considering the spatial configuration relationship between organic matter and clay minerals

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Petroleum Science 2022年第5期19卷 1950-1963页

作者： zhi-Ye Gao Shu-ling Xiong Lin Wei State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Unconventional Petroleum Research Institute China University of PetroleumBeijing102249China School of Energy Resources China University of GeosciencesBeijing100083China

The water adsorption by shale significantly affects shale gas content and its seepage ***,the mechanism of water adsorption by shale is still unclear due to its strong heterogeneity and complicated pore *** relationship between the adsorbed water content at different relative humidities(RHs)and shale compositions,as well as shale pore structure and the spatial configuration relationship between organic matter(OM)and clay minerals,was investigated to clarify the controlling factors and mechanisms of water adsorption by Longmaxi Formation shale from the Southern Sichuan Basin in ***,the water adsorption process could be generally divided into three different stages from 0%RH to 99%***,the Johnston’s clay mine ral interlayer pore structure model(JCM),the Freundlich model(FM)and the Dubinin-Astakhov model(DAM)were tested to fit the three water adsorption stages from low RH to high RH,*** fitting results of the JCM and FM at lower RHs were far from good,while the fitting results of DAM at higher RHs were ***,two revised models(LRHM and MRHM)considering the spatial configuration relationship between OM and clay minerals were proposed for the two stages with lower RHs,and performed better fitting results indicating the pronounced effect of the spatial configuration relationship between OM and clay minerals on the water adsorption process of Longmaxi Formation *** outcomes of this study will contribute to clarifying the water distribution characteristics in the pore network of shale samples with variable water contents.

关键词： Longmaxi formation shale Water content OM-clay complexes Spatial occurrence relationship

Effect of Molecular Weight of PEG Soft Segments on Photo-stimulated Selfhealing Performance of Coumarin Functionalized Polyurethanes

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Chinese Journal of Polymer Science 2014年第10期32卷 1286-1297页

作者： Jun ling Min-zhi Rong 章明秋 Technology Centre China Tobacco Yunnan Industrial Co. Ltd Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education GD HPPC Lab School of Chemistry and Chemical Engineering Sun Yat-sen University

Polyurethanes consisting of tri-functional homopolymer of hexamethylene diisocyanate （tri-HDI） and polyethylene glycol （PEG） are synthesized, in which photo-reversible coumarin moieties act as pendant groups. Accordingly, the polyurethanes can be repeatedly self-healed under UV lights at room temperature by taking advantages of the photodimerization and photocleavage habits of coumarin. Molecular weight of the soft segment, PEG, is found to be closely related to the healing performance of the polyurethanes. Lower molecular weight PEG that corresponds to higher initial coumarin concentration in the polymer is critical for obtaining higher healing efficiency in the case of the first healing action. Nevertheless, it does not guarantee high reversibility of the photo-remendability during the repeated healing events. In contrast, the polyurethane with moderate molecular weight PEG has achieved balanced performance. Reaction kinetics is less important for the healing effect.

关键词： Polyurethanes Self-healing Coumarin Photochemistry Reversibility.

PLZF^posc-KIT^pos-delineated A1-A4-differentiating spermatogonia by subset and stage detection upon Bouin fixation

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Asian Journal of Andrology 2019年第3期21卷 309-318页

作者： Rui-ling tang Li-Qing Fan Institute of Reproduction and Stem Cell Engineering School of Basic Medicine Science Central South University Changsha 410078 China

While hallmarks of rodent spermatogonia stem cell biomarkers' heterogeneity have recently been identified, their stage and subset distributions remain unclear. Furthermore, it is currently difficult to accurately identify subset-specific SSC marker distributions due to the poor nuclear morphological characteristics associated with fixation in 4% paraformaldehyde. In the present study, testicular cross-sections and whole-mount samples were Bouin fixed to optimize nuclear resolution and visualized by immunohistochemistry (IHC) and immunofluorescence (IF). The results identified an expression pattern of PLZFhighc-KITpos in A1 spermatogonia, while A2–A4-differentiating spermatogonia were PLZFlowc-KITpos. Additionally, this procedure was used to examine asymmetrically expressing GFRA1 and PLZF clones, asymmetric Apr and false clones were distinguished based on the presence or absence of TEX14, a molecular maker of intercellular bridges, despite having identical nuclear morphology and intercellular distances that were <25 μm. In conclusion, this optimized Bouin fixation procedure facilitates the accurate identification of spermatogonium subsets based on their molecular profiles and is capable of distinguishing asymmetric and false clones. Therefore, the findings presented herein will facilitate further morphological and functional analysis studies and provide further insight into spermatogonium subtypes.

关键词： asymmetric division cellular homolog of feline sarcoma viral oncogene v-kit false clones glial cell line-derived neurotrophic factor receptor alpha 1 promyelocytic leukemia zinc finger spermatogonia stem cell

A TVD Type Wavelet-Galerkin Method for Hamilton-Jacobi Equations

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 303-310页

作者： ling-yan tang Song-he Song Department of Mathematics and System Science Science School National University of Defense Technology Hunan 410073 China

In this paper, we use Daubechies scaling functions as test functions for the Galerkin method, and discuss Wavelet-Galerkin solutions for the Hamilton-Jacobi equations. It can be proved that the schemes are TVD schemes. Numerical tests indicate that the schemes are suitable for the Hamilton-Jacobi equations. Furthermore, they have high-order accuracy in smooth regions and good resolution of singularities.

关键词： Hamilton-jacobi equation wavelet-galerkin method daubechies wavelet TVD method

Species richness patterns and the determinants of larch forests in China

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Plant Diversity 2022年第5期44卷 436-444页

作者： Wen-Jing Fang Qiong Cai Qing Zhao Cheng-Jun Ji Jiang-ling Zhu zhi-Yao tang Jing-Yun Fang School of Ecology and Environmental Science Yunnan UniversityKunming 650091China Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

Larch forests are important for species diversity,as well as soil and water conservation in mountain *** this study,we determined large-scale patterns of species richness in larch forests and identified the factors that drive these *** found that larch forest species richness was high in southern China and low in northern China,and that patterns of species richness along an elevational gradient depend on larch forest *** addition,we found that patterns of species richness in larch forests are best explained by contemporary climatic ***,mean annual temperature and annual potential evapotranspiration were the most important factors for species richness of tree and shrub layers,while mean temperature of the coldest quarter and anomaly of annual precipitation from the Last Glacial Maximum to the present were the most important for that of herb layer and the whole *** structural factors,especially stand density,are also associated with the species richness of larch *** findings that species richness in China's larch forests is mainly affected by energy availability and cold conditions support the ambient energy hypothesis and the freezing tolerance hypothesis.

关键词： Biodiversity Community structure Determinants Geographic pattern Larch forest Species richness

Lewis Base Catalyzed Selenofunctionalization of Alkynes with Acid-Controlled Divergent Chemoselectivity

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Chinese Journal of Chemistry 2024年第14期42卷 1623-1629页

作者： ling-ling Chen Ren-Fei Cao Hua Ke zhi-Min Chen School of Chemistry and Chemical Engineering Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai200240 China Engineering Technology Research Center for Environmental Protection Materials Pingxiang UniversityPingxiangJiangxi337055 China

Lewis base catalyzed and Brønsted acid controlled chemodivergent electrophilic selenofunctionalizations of alkynes were developed for the first *** selenium-containing tetrasubstituted alkenes were readily obtained in moderate to excellent yields with complete E/Z *** the substrates were 1-ethynyl naphthol derivatives,linear selenium-containing tetrasubstituted alkenes were produced via intermolecular oxygen nucleophilic attack in the absence of acid additive;in contrast,cyclic selenium-containing tetrasubstituted alkenes were generated through intramolecular carbon nucleophilic capture with the addition of Brønsted acid.

关键词： Alkynes Electrophilic addition Chemoselectivity Lewis base catalysis Selenofunctionalization

Hypergravity experiments on multiphase media evolution

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Science China(Technological Sciences) 2022年第12期65卷 2791-2808页

作者： CHEN YunMin tang Yao ling DaoSheng WANG YuBing Center for Hypergravity Experiment and Interdisciplinary Research Zhejiang UniversityHangzhou 310058China Key Laboratory of Soft Soils and Geoenvironmental Engineering(Ministry of Education) Zhejiang UniversityHangzhou 310058China

The gravitational field affects the evolution of multiphase media, such as rocks, soil, and alloy melts. Hypergravity increases the body force of matter, enhancing the driving force of the relative motion between substances with different densities and accelerating the evolution of multiphase media. Hypergravity experiments provide a new approach to exploring the motion of multiphase media and solving engineering problems. Hypergravity experiments have been conducted in different disciplines,such as materials science, geological science, and geotechnical engineering. However, the knowledge barriers between various research fields have caused the development of centrifuges/inflight devices and theoretical research on the mechanisms of matter in motion in hypergravity to lag behind the application of hypergravity experiments, limiting the progress in these *** article systematically summarizes and proposes the fundamentals of hypergravity experiments, while the scientific challenge of the nonlinear hypergravity effect induced by high hypergravity on multiphase media evolution is clarified. Evaluation criteria are proposed for the noninertial frame effects of the centrifugal hypergravity field. The development of the high-centrifugal acceleration, large-capacity, and long-beam centrifuges are determined as the future research direction. Representative cases are used to demonstrate the effectiveness and great potential of the hypergravity experiments for the solidification of alloy melts and physical modeling. Challenges in the experimental methodology are also clarified. This paper reviews the fundamentals and applications of hypergravity experiments in various disciplines, pointing out the research direction of hypergravity experiments on multiphase media evolution.

关键词： hypergravity experiments multiphase media centrifuge solidification of alloy melts physical modeling

The boundary conditions for simulations of a shake-table experiment on the seismic response of 3D slope

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 23-32页

作者： tang Liang Cong Shengyi ling Xianzhang Ju Nengpan School of Civil Engineering Harbin Institute of Technology State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology School of Civil Engineering Qingdao Technological University

Boundary conditions can significantly affect a slope＇s behavior under strong earthquakes. To evaluate the importance of boundary conditions for finite element （FE） simulations of a shake-table experiment on the slope response, a validated three-dimensional （3D） nonlinear FE model is presented, and the numerical and experimental results are compared. For that purpose, the robust graphical user-interface ＂SlopeSAR＂, based on the open-source computational platform OpenSees, is employed, which simplifies the effort-intensive pre- and post-processing phases. The mesh resolution effect is also addressed. A parametric study is performed to evaluate the influence of boundary conditions on the FE model involving the boundary extent and three types of boundary conditions at the end faces. Generally, variations in the boundary extent produce inconsistent slope deformations. For the two end faces, fixing the y-direction displacement is not appropriate to simulate the shake-table experiment, in which the end walls are rigid and rough. In addition, the influence of the length of the 3D slope＇s top face and the width of the slope play an important role in the difference between two types of boundary conditions at the end faces （fixing the y-direction displacement and fixing the （y, z） direction displacement）. Overall, this study highlights that the assessment of a comparison between a simulation and an experimental result should be performed with due consideration to the effect of the boundary conditions.

关键词： boundary condition dynamic response soil slope nonlinear finite element analysis shake-table experimentearthquake

The CUSUM statistic of change point under NA sequences

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Applied Mathematics(A Journal of Chinese Universities) 2021年第4期36卷 512-520页

作者： ling Jin LI Xiao-qin YANG Wen-zhi JIAO Jian-ling School of Management Hefei University of TechnologyHefei 230009China Center for Applied Mathematics School of Mathematical SciencesAnhui UniversityHefei 230061China

In this paper,we investigate the CUSUM statistic of change point under the neg-atively associated(NA)*** establishing the consistency estimators for mean and covariance functions respectively,the limit distribution of the CUSUM statistic is proved to be a standard Brownian bridge,which extends the results obtained under the case of an indepen-dent normal sample and the moving average ***,the finite sample properties of the CUSUM statistic are given to show the efficiency of the method by simulation studies and an application on a real data analysis.

关键词： CUSUM statistic limit distribution NA sequences Brownian bridge