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Acta Geologica Sinica(English Edition) 2020年第1期94卷 152-161页

作者： ZHANG Fawang GAN Fuping LUAN Song meng yan ZHENG Zhijie LI Weixuan Institute of Karst Geology Chinese Academy of Geological SciencesGuilin 541004China

A residential building in Guilin City, China, underwent an up-and-down vibration with an amplitude of 2 cm. By eliminating several causes such as earthquake, wind and construction, in combination with the unique karst geological conditions of Guilin, it was inferred that the effect of turbulent karst water is the main contributor to the occurrence of this vibration. Therefore, a geophysical survey was undertaken on the vibration zone and its surroundings. The resutls suggest that the soil in the upper part of the karst grooves shows conspicuous traces of disturbance and the water content has low resistance. A comprehensive analysis indicates that there is a karst strong runoff zone beneath the area. According to the water level and water temperature data collected automatically by the instrument, it can be concluded that the groundwater level had changed significantly twice during this period, so it was determined that the denudation of groundwater strong runoff causes the overlying soil layer to collapse, forming a soil-water soft-flow material with mixed phase. Since the building in this area was supported by friction piles, the groundwater-soil soft-flow material with mixed phase has intense plasticity, and the up-and-down vibration resulted in the change of the friction piles, which caused the up-and-down vibration of the building structure.

关键词： karst building vibration groundwater strong runoff

Microscopic and Fractal Characterization of Organic Matter within Lacustrine Shale Reservoirs in the First Member of Cretaceous Qingshankou Formation,Songliao Basin,Northeast China

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Journal of Earth Science 2020年第6期31卷 1241-1250页

作者： Bo Liu meng yan Xianda Sun Yunfeng Bai Longhui Bai Xiaofei Fu Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development Ministry of EducationNortheast Petroleum UniversityDaqing 163711China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610051China PetroChina Daqing Oilfield Company Daqing 163318China

Understanding the occurrences of different fractions of organic matter in shale reservoirs is very important for the evaluation of shale *** organic-rich shale samples from the first member of the Cretaceous Qingshankou Formation in the Songliao Basin were analyzed with confocal laser scanning microscopy(CLSM)and fluorescence spectral *** results show that the occurrences of different organic components are related to the fabric of samples and vary with *** bulk content of light components is significantly higher than heavy components and exhibits a positive relationship with quartz and feldspar *** light and heavy components are distributed parallel with the lamination in microscopic view in laminated samples,and randomly in massive *** maximum radius of light components in most of the samples is larger than 20μm,while it is smaller for heavy components,indicating the micro fractionation from clay/organic lamina to quartz/feldspar *** depth of enrichment of light components corresponds to the oil maturity of organic *** the distribution of light and heavy components fits the same fractal model,with fractal dimensions ranging between 2.2 and *** CLSM results confirm that it can be a reliable tool for the"sweet spot"exploration.

关键词： confocal laser scanning fractal bitumen lithofacies shale oil

Alteration of ascending colon mucosal microbiota in patients after cholecystectomy

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2436-2450页

作者： Miao-yan Fan Qiao-Li Jiang meng-yan Cui meng-Qi Zhao Jing-Jing Wang Ying-Ying Lu Department of Gastroenterology Jiading Branch of Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 201803China Shanghai Key Laboratory of Pancreatic Diseases Institute of Translational MedicineShanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 201620China Department of Gastroenterology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 201620China

BACKGROUND Cholecystectomy is a successful treatment option for gallstones,although the inci-dence of colorectal cancer(CRC)has notably increased in post-cholecystectomy(PC)***,it remains uncertain whether the altered mucosal micro-biota in the ascending colon is *** total,30 PC patients and 28 healthy controls underwent colonoscopies to collect mucosal biopsy *** patients were divided based on their clinical ***,16S-rRNA gene sequencing was used to analyze the amplicon,alpha diversity,beta diversity,and composition of the bacterial ***-tionally,the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt)database,sourced from the Kyoto Encyclopedia of Genes and Genomes,was used to predict the functional capabilities of the *** PC patients were comparable with healthy ***,PC patients older than 60 years had a distinct composition compared to those under 60 years *** richness was considerably higher at the phylum level in PC ***,Parabacteroides,and Bilophila were more abundant in the PC group than in the control ***,PC patients exhibited greater enrichment in metabolic pathways,specifically those related to lipopolysaccharide biosynthesis and vancomycin group antibiotic production,than *** This study indicated that the mucosal microbiota in PC patients was altered,perhaps offering new perspectives on the treatment possibilities for CRC and diarrhea following cholecystectomy.

关键词： Post-cholecystectomy Ascending colon Mucosal Microbiota Colorectal cancer Diarrhea

Construction of highly stable selenium nanoparticles embedded in hollow nanofibers of polysaccharide and their antitumor activities

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Nano Research 2017年第11期10卷 3775-3789页

作者： Zhaohua Ping Ting Liu Hui Xu yan meng Wenhua Li Xiaojuan Xu Lina Zhang College of Chemistry amp Molecular Sciences Wuhan University Wuhan 430072 China Hubei Key Laboratory of Cell Homeostasis College of Life Sciences Wuhan University Wuhan 430072 China

Nanotechnologies have been exploited to develop safe and effective medicines and *** the present study,a novel functional nanomedicine constructed from a bioactive polysaccharide and selenium nanoparficles （SeNPs） was developed.A highly-branched [3-（1→3）-D-glucan （AF1） with high anti-tumor activity was used to self-assemble hollow nanofibers with an apparent average diameter of 92 nm;Se nanopartides were synthesized via the reduction of sodium *** results of light scattering,transmission electron microscopy,and X-ray diffraction demonstrated that the spherical SeNPs with a mean diameter of 46 nm were entrapped in the cavities of the AF1 hollow nanofibers through the formation of Se-O bonds between SeNPs and AF1,leading to the good dispersion and high stability in water for over 16 *** vitro and in vivo assays indicated that the AF1-Se nanocomposite had higher anti-tumor activities against breast ***,AF1-Se displayed a broad-spectrum inhibition against human cancers with low half maximal inhibitory concentration （IC50） values and low toxicity to normal ***,the inhibition ratio of AF1-Se against MCF-7 cancer cells reached 75% at a concentration of 200 μ***-1 with 29 μM Se content,much higher than that by treatment with AF1 alone,suggesting a strong synergic effect and nano ***,we developed a method for increasing the stability,anti-tumor activity,and safety of SeNPs by wrapping with bioactive polysaccharides.

关键词： selenium nanoparticles stability and dispersion bioactive polysaccharide anti-cancer activity synergistic effect

In-situ scalable fast fabrication of Cu-Cu_(2+1)O nanorods for highly efficient electrocatalytic reduction into ammonia under neutral medium

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Journal of Materials Science & Technology 2023年第24期155卷 111-118页

作者： Sai Huang Ao Wang Xin-Yue Dong Jin-Kun Li yan meng Jun-Ling Song International Joint Research Center for Photoresponsive Molecules and Materials School of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China

The development of a highly efficient and durable electrocatalyst for nitrate reduction reaction(NO_(3)RR)wastewater valorization to ammonia(NH_(3))is a promising ***,it is challenging to design scalable low-cost electrocatalysts with high activity,high selectivity,and long-term stability by a facile and simple ***,we construct this scalable Cu-based nanoarray with muti-oxidation states grown directly on nickel foam(NF)substrate(Cu_(2+1)O@Cu/NF)using a facile molten salt method combined in-situ electrochemical *** as-prepared Cu_(2+1)O@Cu/NF nanoarrays reveal a high NH_(3) yield of 20.14 mg h^(−1) cm^(−2) at−0.95 V vs.a reversible hydrogen electrode(***),Faradaic efficiency of 99.38%at−0.55 V *** in the neutral potassium phosphate(PBS)buffer solution with 50 mM NaNO_(3),which is ascribed to its electron redistribution with abundant oxygen vacancies and favorable charge/mass transfer.

关键词： Cu-Cu2+1O nanorods with multi-oxidation states High NH3 yield Molten salt method Neutral medium Nitrate electrochemical reduction Scalable fabrication

Truncated Estimator of Asymptotic Covariance Matrix in Partially Linear Models with Heteroscedastic Errors

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Acta Mathematicae Applicatae Sinica 2006年第4期22卷 565-574页

作者： yan-meng Zhao Jin-hong You Yong Zhou Department of Mathematics Shenzhen University Shenzhen 518060 China Department of Biostatistics University of North Carolina at Chapel Hill Chapel Hill NC 27599-7400 USA Center for Statistical Research Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

A partially linear regression model with heteroscedastic and/or serially correlated errors is studied here. It is well known that in order to apply the semiparametric least squares estimation （SLSE） to make statistical inference a consistent estimator of the asymptotic covariance matrix is needed. The traditional residual-based estimator of the asymptotic covariance matrix is not consistent when the errors are heteroscedastic and/or serially correlated. In this paper we propose a new estimator by truncating, which is an extension of the procedure in White. This estimator is shown to be consistent when the truncating parameter converges to infinity with some rate.

关键词： Partially linear regression model heteroscedastic serially correlation semiparametric least squares estimation asymptotic covariance matrix

Dynamic recombination of triplet excitons in polymer heterojunctions

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Chinese Physics B 2020年第11期29卷 463-468页

作者： Ya-Dong Wang Jian-Jun Liu Xi-Ru Wang yan-Xia Liu yan meng College of Information Science and Engineering Hebei North UniversityZhangjiakou 075000China Department of Electronics Polytech Nice SophiaNice 06200France Department of Physics Xingtai UniversityXingtai 054001China

The dynamic recombination of two triplet excitons with opposite spins in the heterojunction structure has been investigated using a nonadiabatic evolution *** demonstrate that luminous composite states including the excited polaron and the biexciton can be formed efficiently via the triplet exciton-triplet exciton reaction in the heterojunction and therefore this reaction can enhance the electroluminescence efficiency considerably,which is consistent qualitatively with experimental ***,we find that,although the heterojunctions are beneficial to the generation of luminescent particles,large band offset caused by the heterojunction structure is not helpful to improve the electroluminescence *** addition,the mechanism of the triplet exciton-triplet exciton reaction in heterojunction is different from that of two similar coupling *** results may deepen the understanding of the electroluminescence mechanism in polymer light-emitting devices.

关键词： polymers electron-lattice interaction excitons

Effect of seepage on soil arching effect in deep shield tunnel

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Underground Space 2023年第5期12卷 218-233页

作者： Xu Song Fan-yan meng Ren-Peng Chen Han-Lin Wang Huai-Na Wu Research Center for Advanced Underground Space Technologies of Hunan University Changsha 410082China Key Laboratory of Building Safety and Energy Efficiency of the Ministry of Education Hunan UniversityChangsha 410082China College of Civil Engineering Hunan UniversityChangsha 410082China

Shield tunneling and post-tunneling steady seepage are accompanied by stress and displacement variations,which could induce and influence the soil arching *** there are many studies on the tunneling-induced soil arching effect,the research about the effect of seepage on soil arching effect is extremely *** this study,a numerical model is firstly established and verified by field ***,a series of numerical models,whose simulation method of steady seepage is verified by adopting the conformal mapping technique,are established to study the soil arching evolution of deep-buried tunneling and post-construction steady *** results indicate that seepage leads to an increase in effective vertical stress,which is consistent with the existing *** seepage weakens the soil arching effect resulting in the height of the arch zone reducing from 2.38D(D is the tunnel diameter)to *** seepage leads to the further development of ground consolidation settlement,but the differential displacement in the soil mass *** ground reaction curve in the steady seepage condition shows a bigger value than that after *** is reasonable to control the ground loss ratio in the range of 0.5–1.0%,which can minimize overburden pressure with moderate ground deformation.

关键词： Soil arching effect Steady seepage Numerical simulation Deep shield tunnel Stress change

Origin of Modulus Improvement for Epoxide-terminated Hyperbranched Poly(ether sulphone)/DGEBA/TETA Systems

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Chinese Journal of Polymer Science 2018年第8期36卷 991-998页

作者： Xue-Pei Miao Dao-Jian Cheng Ya-Dong Dai yan meng Xiao-Yu Li Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China Neo Trident Technology Ltd (Beijing) Beijing 100190 China

It has been experimentally shown that epoxide-terminated hyperbranched polyether sulphone （EHBPES） can significantly improve the mechanical properties of traditional diglycidyl ether of bisphenol A/triethylenetetramine （DGEBA/TETA） systems, but the origin of the improvement is still unclear. In this work, we used molecular dynamics （MD） simulations to gain a thorough understanding of the origin of modulus improvement for EHBPES/DGEBA/TETA systems. It is found that the modulus of EHBPES/DGEBA/TETA systems increases with the increase of EHBPES loading. In addition, the crosslinking density, cohesive energy density （CED）, and free volume can be used to understand the modulus for EHBPES/DGEBA/TETA systems. It is shown that the highest modulus is achieved at 7 wt% EHBPES loading due to the highest crosslinking density and CED. When EHBPES loading is below 7 wt%, the higher CED and crosslinking density are responsible for the higher modulus. At higher loadings （〉 7 wt%）, the decreased modulus is closely related to the decreased crosslinking density and increased fractional free volume. It is expected that our results could be of great implications for designing high-performance epoxy materials.

关键词： Modulus Molecular simulation Epoxy resin

Mechanochemical strategy assisted morphology recombination of COFs for promoted kinetics and LiPS transformation in Li-S batteries

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Green Energy & Environment 2024年第12期9卷 1822-1834页

作者： Yunchen Ge yan meng Lin Liu Jianming Li Xuechun Huang Dan Xiao Institute of New Energy and Low-Carbon Technology(INELT) Sichuan UniversityChengdu610000SichuanChina School of Chemical Engineering and College of Chemistry Sichuan UniversityChengdu610065SichuanChina

A covalent organic frameworks(COFs)material with regular pores and stable structure can be used as the host of lithium-sulfur batteries to improve battery kinetics and polysulfides ***,we designed and synthesized two kinds of rod-liked bulk COFs by adjusting different pore sizes(COF-BTD and COF-TFB),unfortunately,the active sites masking and sluggish kinetics have not met our ***,the available layered COFs prepared from mechanochemical can expose abundant active sites and favorable kinetics than bulk ***,simple mechanical ball milling is applied to activate the above COFs(M-COFs group).It is worth noting that layered R-COF-BTD is directly synthesized from rod-liked precursors by simple morphological reconstruction.A series of characterization methods are used to systematically explore the advantages of the group of M-COFs@S electrodes in the cycling process,including the effects of specific morphology on the kinetics and transformation of *** research provides a feasible plan for the development and selection of the host material of lithium-sulfur batteries.

关键词： Covalent organic frameworks Ball milling Recombination of morphology Li–S batteries