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Petroleum Science 2021年第6期18卷 1760-1775页

作者： Dao-Yi Zhu Zhi-hua Deng Si-Wei Chen State Key Laboratory of Petroleum Resources and Prospecting and Petroleum School China University of Petroleum-Beijing at KaramayKaramay834000XinjiangChina

Polymer gel systems have been widely applied to control excessive water and improve oil recovery(IOR)in petroleum *** are usually divided into two main types,in-situ cross-linked polymer gels,and pre-formed polymer *** recent years,nuclear magnetic resonance(NMR) technology has been gradually applied to the research of polymer gel systems due to its unique analysis *** paper is intent to review these works *** in-situ cross-linked polymer gel systems,NMR can be used to characterize the chemical structure changes of the polymer,the cross-linker,and the auxiliary agent in the formulation of the polymer gel ***,the gelation time and the gel strength of the in-situ cross-linked polymer gel systems can also be measured by *** pre-formed polymer gels,NMR can be employed to detect the chemical structure of the designed ***,the NMR method can evaluate the plugging,water control,and oil improvement performance of the polymer gels in porous media without using *** review can help readers build a more systematic understanding of the application of NMR technology in polymer gel systems for IOR and help re searchers to more deeply study the performance of polymer gel systems.

关键词： Nuclear magnetic resonance Polymer gels Gelation time Gel strength Conformance control

On Be/X-ray binaries with an intermediate-mass black hole

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Research in Astronomy and Astrophysics 2010年第7期10卷 672-680页

作者： Tao Li Xiang-dong Li Department of Astronomy Nanjing University Nanjing 210093 China Key Laboratory of Modern Astronomy and Astrophysics （Nanjing University） Ministry of Education Nanjing 210093 China

We adopt the tidal truncation model proposed by Negueruela and Okazaki for Be/X-ray binaries to investigate the influence of intermediate-mass black holes （IMBHs） on Be-star disks. We show that the viscous decretion disks around Be stars are generally truncated ineffectively under the tidal force of IMBHs. Combining this with observations of Be/X-ray binaries, we suggest that Be/IMBH X-ray binaries may appear as recurrent luminous X-ray transients with quasi-periodic X-ray outbursts.

关键词： black hole physics -- circumstellar matter -- stars emission-line, Be -- X-rays binaries

Numerical modeling of solute transport in deformable unsaturated layered soil

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Water Science and Engineering 2017年第3期10卷 184-196页

作者： Sheng Wu dong-sheng Jeng Cities Research Institute Griffith School of EngineeringGriffith UniversitySouthport 4222Australia

The effect of soil stratification was studied through numerical investigation based on the coupled model of solute transport in deformable unsaturated soil. The theoretical model implied two-way coupled excess pore pressure and soil deformation based on Biot's consolidation theory as well as a one-way coupled volatile pollutant concentration field developed from the advection-diffusion theory. Embedded in the model, the degree of saturation, fluid compressibility, self-weight of the soil matrix, porosity variance, longitudinal dispersion, and linear sorption were computed. Based on simulation results of a proposed three-layer landfill model using the finite element method, the multi-layer effects are discussed with regard to the hydraulic conductivity, shear modulus, degree of saturation, molecular diffusion coefficient, and thickness of each layer. Generally speaking, contaminants spread faster in a stratified field with a soft and highly permeable top layer; soil parameters of the top layer are more critical than the lower layers but controlling soil thicknesses will alter the results. This numerical investigation showed noticeable impacts of stratified soil properties on solute migration results, demonstrating the importance of correctly modeling layered soil instead of simply assuming the averaged properties across the soil profile.

关键词： Solute transport Layered soil Consolidation Unsaturated soil Deformable media

Impacts of multi-scenario land use change on ecosystem services and ecological security pattern: A case study of the Yellow River Delta

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Research in Cold and Arid Regions 2024年第1期16卷 30-44页

作者： Xuehua Cen hua Zhang College of Geography and Environmental Science Northwest Normal UniversityLanzhouGansu 730070China

The Yellow River Delta(YRD), a critical economic zone along China's eastern coast, also functions as a vital ecological reserve in the lower Yellow River. Amidst rapid industrialization and urbanization, the region has witnessed significant land use/cover changes(LUCC), impacting ecosystem services(ES) and ecological security patterns(ESP). Investigating LUCC's effects on ES and ESP in the YRD is crucial for ecological security and sustainable development. This study utilized the PLUS model to simulate 2030 land use scenarios, including natural development(NDS), economic development(EDS), and ecological protection scenarios(EPS). Subsequently, the InVEST model and circuit theory were applied to assess ES and ESP under varying LUCC scenarios from 2010 to 2030. Findings indicate:(1) Notable LUCC from 2010 to 2030, marked by decreasing cropland and increasing construction land and water bodies.(2) From 2010 to 2020, improvements were observed in carbon storage,water yield, soil retention, and habitat quality, whereas 2020–2030 saw increases in water yield and soil retention but declines in habitat quality and carbon storage. Among the scenarios, EPS showed superior performance in all four ES.(3) Between 2010 and 2030, ecological sources, corridors, and pinchpoints expanded, displaying significant spatial heterogeneity. The EPS scenario yielded the most substantial increases in ecological sources,corridors, and pinchpoints, totaling 582.89 km^(2), 645.03 km^(2),and 64.43 km^(2), respectively. This study highlights the importance of EPS, offering insightful scientific guidance for the YRD's sustainable development.

关键词： Land use change Multi-scenario simulation Ecosystem services Ecological security pattern The Yellow River Delta Circuit theory

SNPTransformer:A Lightweight Toolkit for Genome-Wide Association Studies

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Genomics, Proteomics & Bioinformatics 2010年第4期8卷 268-273页

作者： Changzheng dong School of Medicine Ningbo University Ningbo 315211 China

High-throughput genotyping chips have produced huge datasets for genome-wide association studies （GWAS） that have contributed greatly to discovering susceptibility genes for complex diseases. There are two strategies for performing data analysis for GWAS. One strategy is to use open-source or commercial packages that are designed for GWAS. The other is to take advantage of classic genetic programs with specific functions, such as linkage disequilibrium mapping, haplotype inference and transmission disequilibrium tests. However, most classic programs that are available are not suitable for analyzing chip data directly and require custom-made input, which results in the inconvenience of converting raw genotyping files into various data formats. We developed a powerful, user-friendly, lightweight program named SNPTransformer for GWAS that includes five major modules （Transformer, Operator, Previewer, Coder and Simulator）. The toolkit not only works for transforming the genotyping files into ten input formats for use with classic genetics packages, but also carries out useful functions such as relational operations on IDs, previewing data files, recoding data formats and simulating marker files, among other functions. It bridges upstream raw genotyping data with downstream genetic programs, and can act as an in-hand toolkit for human geneticists, especially for non-programmers. SNPTransformer is freely available at http：//***.

关键词： genome-wide association studies tool genotyping files conversion

Numerical analysis of added mass and damping of elastic hydrofoils

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Journal of Hydrodynamics 2020年第5期32卷 1009-1023页

作者： Jia-sheng Li Ye-gao Qu Hong-xing hua School of Naval Architecture and Ocean Engineering Huazhong University of Science and TechnologyWuhan 430074China Hubei Provincial Engineering Research Center of Data Techniques and Supporting Software for Ships(DTSSS) Wuhan 430074China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

A numerical model is proposed for analyzing the effects of added mass and damping on the dynamic behaviors of *** coupled fluid-structure interactions(FSIs)of hydrofoils are analyzed by using the 3-D panel method for the fluid and the finite element method for the *** added mass and damping matrices due to the external fluid of the hydrofoil are asymmetric and computational *** computational inefficiencies associated with these asymmetric matrices are overcome by using a modal reduction technique,in which the first several wet mode vectors of the hydrofoil are employed in the analysis of the FSI *** discretized system of equations of motion for the hydrofoil are solved using the Wilson-6 *** present methods are validated by comparing the computed results with those obtained from the finite element *** is found that the stationary flow is sufficient for determining the wet modes of the hydrofoil under the condition of single-phase potential flow and without phase *** the case of relatively large inflow velocity,the added damping of the fluid can significantly affect the structural responses of the hydrofoil.

关键词： Fluid-structure interaction(FSI) hydroelastic response hydrofoil added mass added damping

Dynamics of freezing/thawing indices and frozen ground from 1900 to 2017 in the upper Brahmaputra River Basin, Tibetan Plateau

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Advances in Climate Change Research 2021年第1期12卷 6-17页

作者： LIU Lei LUO dong-Liang WANG Lei huaNG Ya-dong CHEN Fang-Fang State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences320 Donggang WestRoadLanzhou730000China University of Chinese Academy of Sciences Beijing100049China Institute of Tibetan Plateau Research Chinese Academy of Sciences16 Cuilin RoadChaoyang DistrictBeijing100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences 16 Cuilin RoadChaoyang DistrictBeijing100101China

Dynamics of the frozen ground are key to understand the changes of eco-environment in cold regions,especially for areas with limited field *** this study,we analyzed the spatial and temporal variations of the ground surface freezing and thawing indices from 1900 to 2017 for the upper Brahmaputra River(also called the Yarlung zangbo River in China)Basin(UBRB),southwestern Tibetan Plateau,with the air freezing and thawing indices using the University of Delaware(UDEL)monthly gridded air temperature *** abrupt change years for air freezing index(AH)and ground surface freezing index(GH)were detected in 1999 and 2002,respectively,and for both air thawing index(ATI)and ground surface thawing index(GTI)were *** the air temperature rising at a rate of 0.006℃ per year over 1900-2017,the AH and GH decreased at a rate of-0.1℃ d per year,while the ATI and GTI increased at rates of 0.3 and 0.5℃ d per year before the abrupt change year,respectively;all changing trends of freezing/thawing indices increased after the abrupt year,which was-2.9,-0.8,7.3,and 21.7℃ d per year for the AH,GFI,ATI,and GTI,*** utilized the surface frost number model to obtain the dynamics of the frozen ground over the *** the empirical coefficient of E was assigned to 1.2,the simulated frozen ground occupied about 53.2%of the whole UBRB in the 1990s,which agreed well with the existing permafrost map published in *** area of frozen ground accounts for 51.5%-54.5%of the UBRB during *** result may facilitate further studies of the multi-interactions among the frozen ground and relevant eco-environment,such as the air-ground surface energy exchange,hydrological cycles,and changes of the active layer thickness over the UBRB.

关键词： Upper Brahmaputra River Basin Tibetan Plateau Surface frost number model Permafrost distribution Dynamics of frozen ground

Updated review on immune factors in pathogenesis of Crohn's disease

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World Journal of Gastroenterology 2018年第1期24卷 15-22页

作者： Na Li Rui-hua Shi Department of Gastroenterology Zhongda HospitalAffiliated Hospital of Southeast UniversityNanjing 210009Jiangsu ProvinceChina Clinical Medical School of Southeast University Nanjing 210009Jiangsu ProvinceChina

Although the incidence of Crohn's disease(CD) in China is not as high as that in European and American countries, there has been a clear increasing trend in recent years. Little is known about its pathogenesis, cause of deferment, and the range of complications associated with the disease. Local and international scholars have presented many hypotheses about CD pathogenesis based on experimental and clinical studies, including genetic susceptibility, immune function defects, intestinal microflora disorders, delayed hypersensitivity, and food antigen stimulation. However, the specific mechanism leading to this immune imbalance, which causes persistent intestinal mucosal damage, and the source of the inflammatory cascade reaction are still unclear. So far, the results of research studies differ locally and internationally. This paper presents the most current research on immune factors in the pathogenesis of CD.

关键词： pathogenesis immune immunotherapy intestinal inflammation Crohn’s disease cytokines lymphocytes T lymphocytes

OTFS on Overspread Doubly Selective Channel

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China Communications 2024年第11期21卷 205-215页

作者： Qing hua Liu Yun Shi Xiayang Yu hua Ji Fei Cui Yinming College of Software Engineering Zhengzhou University of Light IndustryZhengzhou 450002China School of Internet Finance and Information Engineering Guangdong University of FinanceGuangzhou 510520China School of Electronic and Information Engineering South China University of TechnologyGuangzhou 510641China

The orthogonal time frequency space(OTFS)modulation proposed in recent years is considered to have superior performance than orthogonal frequency division multiplexing(OFDM)for the doubly selective(DS)*** works in the existing literature on OTFS mainly focus on the cases where the channels are underspread(i.e.,the product of the delay spread and the Doppler spread is less than 1).In the scenario of overspread DS channel,which has large delay spread and severe Doppler spread,such as underwater acoustic(UWA)channel,the channel model in delay-Doppler(DD)Domain derived by existing work is no longer *** this paper,we derive a more generalized expression of the channel model in delay-Doppler domain,which allows the product of the delay spread and Doppler spread to be larger *** result shows that the existing channel model is just a special case of the one we *** the proposed channel matrix in DD domain,we build the OTFS detectors with the minimum mean square error(MMSE)and message passing(MP)algorithms on overspread doubly selective ***,simulation results are presented to verify the theoretical derivation and the effectiveness of the detectors.

关键词： delay-Doppler domain doubly selective channel OTFS overspread underwater acoustic communications

Intensive peatland wildfires during the Aptian-Albian oceanic anoxic event 1b:Evidence from borehole SK-2 in the Songliao Basin,NE China

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Journal of Palaeogeography 2022年第3期11卷 448-467页

作者： Zhi-Hui Zhang Da-Wei Lü Tian-Tian Wang dong-Zhao An Hai-Yan Liu dong-dong Wang Cheng-Shan Wang Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina Institute of Earth Sciences China University of GeosciencesBeijing 100083China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Chinese Academy of Geological Sciences Beijing 100037China

The Cretaceous has been considered a“high-fire”world accompanied by widespread by-products of combustion in the rock *** mid-Cretaceous oceanic anoxic event 1b(OAE1b)is marked by one of the major perturbations in the global carbon cycle characterized by deposition of organic-rich sediments in both marine and terrestrial ***,our understanding is still limited on changes in wildfire activity during OAE1b ***,we carried out a comprehensive analysis,including organic carbon isotope(δ^(13)C_(org)),total organic carbon(TOC),coal petrology,trace elements,and pyrolytic polycyclic aromatic hydrocarbons(pyroPAHs),of coal seams of the middle Aptian to early Albian Shahezi Formation from borehole SK-2 in Songliao Basin,Northeast *** negativeδ^(13)C_(org) excursions in the Shahezi Formation can be corresponded with the 113/Jacob and Kilian sub-events of ***,the intensive peatland wildfires have been identified during the sub-event periods of OAE1b based on the co-occurrence of high abundance of charcoal and pyroPAHs at that *** addition,Sr/Ba,Sr/Cu and Sr/Rb ratios demonstrate that enhanced peatland wildfires were controlled by dryer climate conditions owing to episodic northward migration of arid zones in East Asia related with rising global temperature during the sub-events of *** climate-driven extensive wildfire activity in the mid-latitude terrestrial ecosystems can be a contributing factor for OAE1b through the increased flux of nutrients fuelling primary producers in the lake and marine environments and leading to more speculative anoxia to allow the deposition of organic-rich *** results provide essential understanding of the importance of wildfires in driving mechanism of oceanic anoxic events(OAEs)in Earth's history.

关键词： Lower Cretaceous OAEs Peatland Wildfire Coals