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Simultaneous inversion of permeability,skin and boundary from pressure transient test data in three-dimensional single well reservoir model

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Petroleum Research 2024年第2期9卷 265-272页

作者： Arvind Kumar Lin liang Keka Ojha Schlumberger India Indian Institute of Technology(ISM) DhanbadIndia

This study presents a novel approach for simultaneous inversion of the key reservoir parameters like horizontal permeability,vertical permeability,skin,and boundary distances for spatial distribution across the grid cells in a 3D single well reservoir model(SWRM).These parameters are first estimated from the standard pressure transient analysis of well test pressure and rate data,which also act as a priori for the inverse problem.A field-worthy layer cake geological model is prepared based on the prior information obtained from pressure transient analysis,followed by a sequential flow simulation of field well test *** simulation results provide the model pressure versus rate data as the synthetic data for this study.A cost function is defined incorporating the well test pressure data and model pressure data,which would determine the *** inversion process is to optimize the spatial distribution of reservoir parameters to minimize the difference between the measured pressure transient data and the modelled one,which is obtained from the multiphase fluid flow simulator that solves the implicit black-oil fluid-flow diffusivity equations at every step.A Gauss-Newton(GN)inversion scheme is used for the *** reliability of inversion results depends on the accuracy of priori reservoir parameters fed to the solver,which can be refined if required through uncertainty parameter optimization(UPO).This approach helps to obtain a faster and reliable update of reservoir parameters in a layer cake homogeneous geomodel,hereby introducing the required *** increases the confidence and reliability of a geomodel,which is further used for various production prediction strategies.

关键词： Well test Pressure transient Inversion Permeability Boundary

Information Conductivity:Universal Performance Measure for Semantic Communications

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China Communications 2024年第7期21卷 17-36页

作者： liang Zijian Niu Kai Zhang Ping Key Laboratory of Universal Wireless Communications Ministry of Education(Beijing University of Posts and Telecommunications)Beijing 100876China Peng Cheng Laboratory Shenzhen 518055China State Key Laboratory of Networking and Switching Technology(Beijing University of Posts and Telecommunications) Beijing 100876China

As a novel paradigm,semantic communication provides an effective solution for breaking through the future development dilemma of classical communication ***,it remains an unsolved problem of how to measure the information transmission capability for a given semantic communication method and subsequently compare it with the classical communication *** this paper,we first present a review of the semantic communication system,including its system model and the two typical coding and transmission methods for its *** address the unsolved issue of the information transmission capability measure for semantic communication methods,we propose a new universal performance measure called Information *** provide the definition and the physical significance to state its effectiveness in representing the information transmission capabilities of the semantic communication systems and present elaborations including its measure methods,degrees of freedom,and progressive *** results in image transmission scenarios validate its practical applicability.

关键词： information conductivity information transmission capability semantic communications system model universal performance measure

High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： Shang-Yu Si Zhong-liang Li Wen-Hong Jia Lian Xue Hong-Xin Luo Jian-Cai Xu Bai-Fei Shen Lin-Gang Zhang liang-liang Ji Yu-Xin Leng Ren-Zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was *** result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet ***,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

Electrospun PCL/gelatin/arbutin nanofiber membranes as potent reactive oxygen species scavengers to accelerate cutaneous wound healing

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Regenerative Biomaterials 2024年第3期3卷 43-55页

作者： Mindong Du Shuhan Liu Nihan Lan Ruiming liang Shengde liang Maoqiang Lan Disen Feng Li Zheng Qingjun Wei Ke Ma Department of Orthopaedics Trauma and Hand Surgery The First Affliated Hospital of Guangxi Medical UniversityGuangxi Medical UniversityNanning 530521China Guangxi Engineering Center in Biomedical Materials for Tissue and Organ Regeneration The First Affliated Hospital of Guangxi Medical UniversityGuangxi Medicar UniversityNanning530021China Guangxi Collaborative Innovation Center for Biomedicine The First Affliated Hospital of Guangxi Medical UniversityGuangxi Medical UniversityNanning 530021China Department of Plastic&Cosmetic Surgery.The First Affliated Hospital of Guangxi Medical University Guangxi Medical UniversityNanning 530021China Pharmaceutical College Guangxi Medical UniversityNanning530021China

The presence of excessive reactive oxygen species(Ros)at a skin wound site is an important factor affecting wound *** scavenging,which regulates the ROS microenvironment,is essential for wound *** this study,we used novel electrospun PCL/gelatin/arbutin(PCL/G/A)nanofibrous membranes as wound dressings,with PCL/gelatin(PCL/G)as the backbone,and plantderived arbutin(hydroquinone-β-D-glucopyranoside,ARB)as an effective antioxidant that scavenges ROos and inhibits bacterial infection in *** loading of ARB increased the mechanical strength of the nanofibres,with a water vapour transmission rate of more than 2500g/(m^(2)×24h),and the water contact angle decreased,indicating that hydrophilicity and air permeability were significantly *** release and degradation experiments showed that the nanofibre membrane controlled the drug release and exhibited favourable *** experiments showed that the PCL/G/A nanofibre membranes were biocompatible,and DPPH and ABTS+radical scavenging experiments indicated that PCL/G/A could effectively scavenge ROS to reflect the antioxidant *** addition,haemostasis experiments showed that PCL/G/A had good haemostatic effects in vitro and in *** vivo animal wound closure and histological staining experiments demonstrated that PCL/G/A increased collagen deposition and remodelled epithelial tissue regeneration while showing good in vivo biocompatibility and *** conclusion,we successfully prepared a multifunctional wound dressing,PCL/G/A,for skin wound healing and investigated its potential role in wound healing,which is beneficial for the clinical translational application of phytomedicines.

关键词： arbutin nanofiber membranes wound dressing reactive oxygen species

Insights into the provenance implication of leaf wax n-alkanes along the lower Yellow River

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Science China Earth Sciences 2024年第6期67卷 2001-2018页

作者： liang ZHANG Jinzhao LIU Chong JIANG Fei ZHANG Zhisheng AN School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China National Observation and Research Station of Earth Critical Zone on the Loess Plateau of Shaanxi Xi’an 710061China

Serving as one of the largest rivers in terms of both sediment and organic carbon transport fluxes in the world,the Yellow River plays a crucial role in regional biogeochemical process as well as in the global carbon ***,although a large number of studies have been carried out on the flux,composition,source and seasonal variation of total particulate organic carbon in the Yellow River so far,studies on molecular biomarkers at different spatial and temporal scales are still *** this study,we focus on the molecular and hydrogen isotopic properties of leaf wax n-alkanes among different types of samples which obtained from different seasons(flood ***-flood)along the lower Yellow *** molecular distribution of n-alkanes show that the riparian topsoils are subject to inputs from the overlying vegetation,while the suspended sediments from the flood season are characterized by the mixing of soil materials which originate from various stratigraphy with different ages on the Chinese Loess *** to the contrasting hydrodynamic conditions,the n-alkanes in suspended sediments also show distinct molecular composition between flood and non-flood ***,considering the effect of climatic factors,the proportion of monocots in flood-season suspended sediments is calculated from a semi-quantitative perspective using δ^(2)H_(wax).Our findings may bring to light new considerations for the interpretation of leaf wax proxies in studies of organic matter sources of Yellow River.

关键词： Molecular distribution Hydrogen isotopic composition Leaf wax n-alkanes Suspended sediments Lower Yellow River

An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi Liu Xue-Dong Li liang Cheng Li Liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

Crust and Upper Mantle Density Structures beneath the Eastern Tianshan Region and Its Tectonic Implications

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Journal of Earth Science 2024年第3期35卷 828-838页

作者： Yiming Liu Chao Chen Qing liang Zhengwang Hu Hubei Subsurface Multi-Scale Imaging Key Laboratory School of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China

The deformation mechanisms of the Tianshan orogenic belt(TOB)are one of the most important unresolved issues in the collision of the Indian and Eurasian *** better understand the lithospheric deformation of the eastern Tianshan orogenic belt,we combined the S-wave tomography and gravity data to develop a three-dimensional(3D)density model of the crust and upper mantle beneath the eastern Tianshan *** show that the crust of the eastern Tianshan is mainly characterized by positive density anomalies,revealing widespread subduction-related magmatism during the *** however have also observed extensive low-density anomalies beneath the eastern Tianshan at depths deeper than~100 km,which is likely linked to a relatively hot *** most fundamental differences of the lithosphere within the eastern Tianshan occur in the uppermost *** uppermost mantle layers in the Bogda Shan and Harlik Shan are relatively *** is likely associated with an eclogite body in the uppermost *** most significant negative anomaly of the uppermost mantle is however found in the Jueluotage tectonic belt and the central Tianshan Block and is possibly associated with depleted mantle *** suggest that these differences related to compositional changes may control the strength of the lithospheric mantle and have affected the uplift of the northern and southern segments of the eastern Tianshan after the Permian.

关键词： constrained inversion gravity anomaly three-dimensional lithospheric density structure eastern Tianshan geodynamics geophysics.

Rainbow Pancyclicity in a Collection of Graphs Under the Dirac-type Condition

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 269-274页

作者： Lu-yi LI Ping LI Xue-liang LI Center for Combinatorics and LPMC Nankai UniversityTianjin 300071China School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710062China

Let G={Gi:i∈[n]} be a collection of not necessarily distinct n-vertex graphs with the same vertex set V,where G can be seen as an edge-colored(multi)graph and each Gi is the set of edges with color i.A graph F on V is called rainbow if any two edges of F come from different Gis’.We say that G is rainbow pancyclic if there is a rainbow cycle Cℓof lengthℓin G for each integerℓ2[3,n].In 2020,Joos and Kim proved a rainbow version of Dirac’s theorem:Ifδ(Gi)≥2/n for each i∈[n],then there is a rainbow Hamiltonian cycle in *** this paper,under the same condition,we show that G is rainbow pancyclic except that n is even and G consists of n copies of Kn/2,n/*** result supports the famous meta-conjecture posed by Bondy.

关键词： rainbow Hamiltonian cycle rainbow pancyclic meta-conjecture

Hydrogel-supported poly(L-lactic acid) and polystyrene microsphere-based three-dimensional culture systems for in vitro cell expansion

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Frontiers of Materials Science 2024年第2期18卷 129-137页

作者： Huaying Hao Lihong Sun Jiaxuan Chen Jun liang State Key Laboratory of Food Nutrition and Safety Tianjin University of Science&TechnologyTianjin 300457China College of Light Industry Science and Engineering Tianjin University of Science&TechnologyTianjin 300457China College of Food Science and Engineering Tianjin University of Science&TechnologyTianjin 300457China

The in vitro expansion of stem cells is important for their application in different life science fields such as cellular tissue and organ *** objective of this paper was to achieve static cell culture in vitro through peptide hydrogel-supported microspheres(MSs).The peptides,with their gel-forming properties,microstructures,and mechanical strengths characterized,were found to have good support for the MSs and to be *** internal structures of poly(L-lactic acid)microspheres(PLLA-MSs)and polystyrene microspheres(PS-MSs)made in thelaboratory were observed and statistically analyzed in terms of particle size and pore size,following which the co-cultured MSs with cells were found to have good cell *** addition,three-dimensional(3D)culturing of cells was performed on the peptide and microcarrier composite scaffolds to measure cell viability and cell *** results showed that the peptides could be stimulated by the culture medium to self-assembly form a 3D fiber network *** the peptide-Ms composite scaffold-based cell culture system,further enhancement of the cell culture effect was *** peptide-Ms composite scaffolds have great potential for the application in 3D cell culture and in vitro cellexpansion.

关键词： microcarrier microsphere peptide hydrogel cell scaffold three-dimensional culture cell expansion