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Pore-scale simulation of water/oil displacement in a water-wet channel

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Frontiers of Chemical Science and Engineering 2019年第4期13卷 803-814页

作者： jin Zhao Guice yao Dongsheng Wen School of Chemical and Process Engineering University of LeedsLeeds LS29JTUK School of Aeronautic Science and Engineering Bcihang UniversityBeijing 100191China

Water/oil flow characteristics in a water-wet capillary were simulated at the pore scale to increase our understanding on immiscible flow and enhanced oil *** of fluid method was used to capture the interface between oil and water and a pore-throat connecting structure was established to investigate the effects of viscosity,interfacial tension(IFT)and capillary number(Ca).The results show that during a water displacement process,an initial continuous oil phase can be snapped off in the water-wet pore due to the capillary *** altering the viscosity of the displacing fluid and the IFT between the wetting and non-wetting phases,the snapped-off phenomenon can be eliminated or reduced during the displacement.A stable displacement can be obtained under high Ca number *** displacement effects can be obtained at the same Ca number due to its significant influence on the flow state,i.e.,snapped-off flow,transient flow and stable flow,and ultralow IFT alone would not ensure a very high recovery rate due to the fingering flow occurrence.A flow chart relating flow states and the corresponding oil recovery factor is established.

关键词： VOF pore scale immiscible displacement EOR snap-off Ca

Shifting curves based on the detector integration effect for x-ray phase contrast imaging

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Chinese Physics B 2017年第2期26卷 512-515页

作者： Jun Yang jin-ChuanGuo yao-HuLei Ming-Hao yi Li Chen Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Optoelectronic Engineering Shenzhen University Shenzhen 518060 China

In theory, we find that the actual function of the analyzer grating in the Talbot–Lau interferometer is segmenting the self-images of the phase grating and choosing integral areas, which make sure that each period of self-images in one detector pixel contributes the same signal to the detector. Furthermore, in the case of the lack of an analyzer grating, the shifting curves are still existent in theory as long as the number of fringes is non-integral in a detector pixel, which is a sufficient condition for creating shifting curve. The sufficient condition is available for not only the Talbot–Lau interferometer and the inverse geometry of Talbot–Lau interferometer, but also the x-ray phase contrast imaging system based on geometrical optics. In practical applications, we propose a method to improve the performances of the existing systems by employing the sufficient condition. This method can shorten the system length, is applicable to large period gratings, and can use the detectors with large pixels and large field of view. In addition, the experimental arrangement can be simplified due to the lack of an analyzer grating. In order to improve detection sensitivity and resolution, we also give an optimal fringe *** believe that the theory and method proposed here is a step forward for x-ray phase contrast imaging.

关键词： x-ray phase contrast imaging Talbot–Lau interferometer x-ray imaging

Drivers of the differentiation between broad-leaved trees and shrubs in the shift from evergreen to deciduous leaf habit in forests of eastern Asian subtropics

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Plant Diversity 2023年第5期45卷 535-543页

作者： yi jin Hong Qian Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China Guizhou Normal UniversityGuiyang 550025China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL62703USA

In eastern Asian subtropical forests,leaf habit shifts from evergreen to deciduous broad-leaved woody plants toward higher *** shift has been largely explained by the greater capacity of deciduous broad-leaved plants to respond to harsh climatic conditions(e.g.,greater seasonality).The advantages of deciduous leaf habit over evergreen leaf habit in more seasonal climates have led us to hypothesize that leaf habits would shift in response to climate changes more conspicuously in forest canopy trees than in forest understory ***,we hypothesize that in the forests of the subtropics,plants at higher latitudes,regardless of growth form,would better tolerate seasonal harsh climates,and hence show less differentiation in leaf habit shift,compared to those at lower *** test these two hypotheses,we modelled the proportion of deciduous broad-leaved species and the incidence of deciduous and evergreen broad-leaved species in woody angiosperm species compositions of ten largesized forest plots distributed in the Chinese *** found that the rate of leaf habit shift along a latitudinal gradient was higher in forest trees than in forest *** also found that the differentiation in leaf habit shift between trees and shrubs is greater at lower latitudes(i.e.,warmer climates)than at higher latitudes(i.e.,colder climates).These findings indicate that specialized forest plants are differentially affected by climate in distinct forest strata in a manner dependent on latitudinal *** differences in forest plant response to changes in climate suggest that global climate warming will alter growth forms and geographical distributions and ranges of forests.

关键词： Functional trait Leaf life span Forest dynamics plot Latitudinal gradient

Are phylogenies resolved at the genus level appropriate for studies on phylogenetic structure of species assemblages?

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Plant Diversity 2021年第4期43卷 255-263页

作者： Hong Qian yi jin Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL62703USA Key Laboratory of State Forestry Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China Guizhou Normal UniversityGuiyang550025China

Phylogenies are essential to studies investigating the effect of evolutionary history on assembly of species in ecological communities and geographical and ecological patterns of phylogenetic structure of species *** phylogenies well resolved at the species level are lacking for many major groups of organisms such as vascular plants,researchers often generate a species-level phylogenies using a phylogeny well resolved at the genus level as a backbone and attaching species to their respective genera in the phylogeny as polytomies or by using a megaphylogeny well resolved at the genus level as a backbone and adding additional species to the megaphylogeny as polytomies of their respective ***,whether the result of a study using species-level phylogenies generated in these ways is robust,compared to that based on phylogenies fully resolved at the species level,has not been ***,we use 1093 angiosperm tree assemblages(each in a 110110 km quadrat)in North America as a model system to address this question,by examining six commonly used metrics of phylogenetic structure(phylogenetic diversity and phylogenetic relatedness)and six climate variables commonly used in *** results showed that(1)the scores of phylogenetic metrics derived from species-level phylogenies resolved at the genus level with species being attached to their respective genera as polytomies are very strongly or perfectly correlated to those derived from a phylogeny fully resolved at the species level(the mean of correlation coefficients is 0.973),and(2)the relationships between the scores of phylogenetic metrics and climate variables are consistent between the two sets of analyses based on the two types of *** study suggests that using species-level phylogenies resolved at the genus level with species being attached to their genera as polytomies is appropriate in studies exploring patterns of phylogenetic structure of species in ecological communities

关键词： Genus-level phylogeny Species-level phylogeny Phylogenetic diversity Phylogenetic relatedness Community phylogenetics Environmental gradient

***: An R package that can generate large phylogenetic trees for plants and animals

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Plant Diversity 2023年第3期45卷 347-352页

The previously released packages of the PhyloMaker series(***,***,and ***2) have been broadly used to generate phylogenetic trees for ecological and biogeographical *** these packages can be used to generate phylogenetic trees for any groups of plants and animals for which megatrees are available,they focus on generating phylogenetic trees for plants based on the megatrees provided by the *** to use these packages to generate phylogenetic trees based on other megatrees is not ***,we present a new tool,which is called ‘***’,and a simple R script that can be used to easily generate large phylogenetic trees for both plants and animals at a relatively fast speed.

关键词： Animals Community phylogenetics Megatree Phylogeny Plants Species list

First total synthesis of (±)-malaysianone A and (±)-tanariflavanones B

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Chinese Chemical Letters 2013年第11期24卷 1027-1029页

作者： jin-Hui Yang Bing-Bing Chen yi-Min Xie yao Feng Xiao-Qin Ma State Key Laboratory Cultivation Base of Natural Gas Conversion Ningxia University

A concise approach for the frst total synthesis of two naturally occurring flavanoids,（）-malaysianone A（1）and（）-tanariflavanones B（2）,has been accomplished with total yields of 12.9%and 10.4%,*** key steps were regioselective deprotection and regioselective synthesis of 5-formaldehyde-8-hydroxy-2-[40-methyl-30-penteneyl]-dihydro-1-benzopyran（8）.

关键词： Malaysianone A Tanariflavanones B Total synthesis Flavanoids

Experiment on the Nonlinear Phenomena in an Electron Cyclotron Resonance Plasma

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Chinese Physics Letters 1996年第12期13卷 916-918页

作者： yao Xin-zi JIANG De-yi Institute of Physics Chinese Academy of SciencesBeijing 100080

Two hysteresis loops and tristable states in an electron cyclotron resonance plasma system have been observed and oscillatory waveforms and their power spectra in different stable state are described in this *** the microwave power was increased,the oscillation with original fundamental frequency gradually transferred to harmonic frequencies and then sudden jumped to a regular oscillation with single fourth harmonic frequency.

关键词： harmonic oscillation Electron

Nanopore-based sensing interface for single molecule electrochemistry

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Science China Chemistry 2019年第12期62卷 1576-1587页

作者： Rui Gao yao Lin yi-Lun ying yi-Tao Long Department of Chemistry University of UtahSalt Lake CityUtah 84112USA School of Chemistry&Molecular Engineering East China University of Science and TechnologyShanghai 200237China State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Nanopore techniques are experiencing a gallop since it walked out the notebook and show its charm on the science *** nanoscale pore offers a single-molecule resolution with a label-free and high-selective manner for the research of molecular structures,molecular dynamics,single-molecule reactions and for a variety of applications in biophysics and *** this review,we introduce the construction of three types of nanopore platforms along with the latest progress in DNA sensing,structure and dynamics analysis of peptides/proteins,and the detection of redox reactions with new sensing ***,we depict nanopore data processing methods which provide an insight of data mining under the background ofbig *** could fully expect the great impact of nanopore techniques on not only for DNA sequencing and sensing applications,but also in protein sequencing and clinical diagnostics.

关键词： nanopore single-molecule sensing nanoelectrochemistry

Fire's effect on chloride ingress related durability of concrete structure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 675-681页

作者： jin Wei-liang ZHANG yi Structural Engineering Institute Zhejiang University Hangzhou 310027 China

This paper describes the effects of fire on durability of reinforced concrete structures, and points out that fire not only damages the chemical composition and physical structure of concrete by high temperature, but also leads to an additional risk due to the generation of polyvinyl chloride (PVC) combustion gases. A mathematical model is proposed to calculate chloride ingress profiles in fire damaged concrete, so as to explore the service life prediction of the structure. Rapid Chloride Migration (RCM) test was carried out to determine the chloride diffusion coefficients for the application of the mathematical model. Finally, the detected results of a reported case testified to the validity of the mathematical model.

关键词： Fire High temperature Polyvinyl chloride (PVC) Mathematical model Rapid Chloride Migration (RCM)