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Experimental study of the effects of a multistage pore-throat structure on the seepage characteristics of sandstones in the Beibuwan Basin:Insights into the flooding mode

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Petroleum Science 2024年第2期21卷 1044-1061页

作者： Lei Wang xiao Lei Qiao-Liang Zhang Guang-Qing Yao Bo Sui xiao-Jun Chen ming-Wei Wang Zhen-Yu Zhou Pan-Rong Wang xiao-Dong Peng Zhanjiang Branch China National Offshore Oil Corporation(CNOOC)LimitedZhanjiang524057GuangdongChina Faculty of Earth Resources China University of Geosciences(Wuhan)Wuhan430074HubeiChina School of Resources and Safety Engineering Chongqing UniversityChongqing400044China School of Engineering University of ManchesterManchester M139WJUK Hainan Branch China National Offshore Oil Corporation(CNOOC)LimitedHaikou570311HainanChina

To investigate the relationship between grain sizes, seepage capacity, and oil-displacement efficiency in the Liushagang Formation of the Beibuwan Basin, this study identifies the multistage pore-throat structure as a crucial factor through a comparison of oil displacement in microscopic pore-throat experiments. The two-phase flow evaluation method based on the Li-Horne model is utilized to effectively characterize and quantify the seepage characteristics of different reservoirs, closely relating them to the distribution of microscopic pores and throats. It is observed that conglomerate sandstones at different stages exhibit significant heterogeneity and noticeable differences in seepage capacity, highlighting the crucial role played by certain large pore throats in determining seepage capacity and oil displacement efficiency. Furthermore, it was found that the displacement effects of conglomeratic sandstones with strong heterogeneity were inferior to those of conventional homogeneous sandstone, as evidenced by multiple displacement experiments conducted on core samples with varying granularities and flooding systems. Subsequently, core-based experiments on associated gas flooding after water flooding were conducted to address the challenge of achieving satisfactory results in a single displacement mode for reservoirs with significant heterogeneity. The results indicate that the oil recovery rates for associated gas flooding after water flooding increased by 7.3%-16.4% compared with water flooding alone at a gas-oil ratio of approximately 7000 m^(3)/m^(3). Therefore, considering the advantages of gas flooding in terms of seepage capacity, oil exchange ratio, and the potential for two-phase production, gas flooding is recommended as an energy supplement mode for homogeneous reservoirs in the presence of sufficient gas source and appropriate tectonic angle. On the other hand, associated gas flooding after water flooding is suggested to achieve a more favorable develop

关键词： Beibuwan Basin Multistage pore-throat structure Multistage seepage characteristics Microscopic visualization Heterogeneity Gas/water flooding Flooding mode

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Defect detection of light guide plate based on improved YOLOv5 networks

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Optoelectronics Letters 2024年第9期20卷 560-567页

作者： xiao ming GONG Yefei WANG Hongding LU mingli GAO Hua School of Electrical Engineering Yancheng Institute of TechnologyYancheng 224007China School of Electrical and Automation Engineering Changshu Institute of TechnologyChangshu 215500China School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318China Wuxi Novo Automation Technology Corporation Wuxi 214000China

Light guide plate(LGP)is a kind of material used in the backlight *** to improve the quality control of LGP has become the focus of research in the *** address issues such as low gray contrast and a high proportion of small target defects in LGP images,an improved you only look once version 5(YOLOv5)neural network based on multi-scale dilation convolution and a novel loss function is proposed.

关键词： network plate light

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Lung ultrasound score evaluation of the effect of pressure-controlled ventilation volume-guaranteed on patients undergoing laparoscopicassisted radical gastrectomy

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1717-1725页

作者： Jian Tan Cheng-ming Bao xiao-Yuan Chen Department of Critical Care Medicine Lishui District People's HospitalNanjing 211200Jiangsu ProvinceChina Department of Ultrasound Medicine Lishui District People's HospitalNanjing 211200Jiangsu ProvinceChina

BACKGROUND Laparoscopic-assisted radical gastrectomy(LARG)is the standard treatment for early-stage gastric carcinoma(GC).However,the negative impact of this proce-dure on respiratory function requires the optimized intraoperative management of patients in terms of *** To investigate the influence of pressure-controlled ventilation volume-guaranteed(PCV-VG)and volume-controlled ventilation(VCV)on blood gas analysis and pulmonary ventilation in patients undergoing LARG for GC based on the lung ultrasound score(LUS).METHODS The study included 103 patients with GC undergoing LARG from May 2020 to May 2023,with 52 cases undergoing PCV-VG(research group)and 51 cases undergoing VCV(control group).LUS were recorded at the time of entering the operating room(T0),20 minutes after anesthesia with endotracheal intubation(T1),30 minutes after artificial pneumoperitoneum(PP)establishment(T2),and 15 minutes after endotracheal tube removal(T5).For blood gas analysis,arterial partial pressure of oxygen(PaO_(2))and partial pressure of carbon dioxide(PaCO_(2))were *** airway pressure(P_(peak)),plateau pressure(Pplat),mean airway pressure(P_(mean)),and dynamic pulmonary compliance(C_(dyn))were recorded at T1 and T2,1 hour after PP establishment(T3),and at the end of the operation(T4).Postoperative pulmonary complications(PPCs)were ***-and postoperative serum interleukin(IL)-1β,IL-6,and tumor necrosis factor-α(TNF-α)were measured by enzyme-linked immunosorbent *** Compared with those at T0,the whole,anterior,lateral,posterior,upper,lower,left,and right lung LUS of the research group were significantly reduced at T1,T2,and T5;in the control group,the LUS of the whole and partial lung regions(posterior,lower,and right lung)decreased significantly at T2,while at T5,the LUS of the whole and some regions(lateral,lower,and left lung)increased *** comparison with the control group,the whole and regional LUS of the research group were reduc

关键词： Lung ultrasound score Pressure-controlled ventilation volume-guaranteed Laparoscopic-assisted radical gastrectomy Blood gas analysis indexes Pulmonary ventilation

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CpG Island Definition and Methylation Mapping of the T2T-YAO Genome

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 69-79页

作者： ming xiao Rui Wei Jun Yu Chujie Gao Fengyi Yang Le Zhang College of Computer Science Sichuan UniversityChengdu 610065China Key Laboratory of Systems Health Science of Zhejiang Province School of Life ScienceHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Precisely defining and mapping all cytosine(C)positions and their clusters,known as CpG islands(CGIs),as well as their methylation status,are pivotal for genome-wide epigenetic studies,especially when population-centric reference genomes are ready for timely ***,we first align the two high-quality reference genomes,T2T-YAO and T2T-CHM13,from different ethnic backgrounds in a base-by-base fashion and compute their genome-wide density-defined and position-defined ***,by mapping some representative genome-wide methylation data from selected organs onto the two genomes,we find that there are about 4.7%–5.8%sequence divergency of variable categories depending on quality *** among the divergent sequences are mostly associated with neurological ***,CGIs associated with the divergent sequences are significantly different with respect to CpG density and observed CpG/expected CpG(O/E)ratio between the two ***,we find that the T2T-YAO genome not only has a greater CpG coverage than that of the T2T-CHM13 genome when whole-genome bisulfite sequencing(WGBS)data from the European and American populations are mapped to each reference,but also shows more hyper-methylated CpG sites as compared to the T2T-CHM13 *** study suggests that future genome-wide epigenetic studies of the Chinese populations rely on both acquisition of high-quality methylation data and subsequent precision CGI mapping based on the Chinese T2T reference.

关键词： T2T-YAO Position-defined CpG island Density-defined CpG island DNA methylation Genome analysis

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Preparation of NiTip/Al composites with controllable phase transformation and damping behavior by friction stir processing

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Science China(Technological Sciences) 2024年第2期67卷 597-607页

作者： WU xiao jiang HongJie LI WangYun LIU ChongYu HUANG HongFeng LIU ShuHui WEI LiLi School of Material Science and Engineering Guilin University of Technology Guilin 541004China Key Laboratory of New Processing Technology for Nonferrous Metal&Materials Ministry of EducationGuilin University of Technology Guilin 541004China School of Mechanical and Electrical Engineering Guilin University of Electronic TechnologyGuilin 541004China

The NiTip/1060Al composites were prepared using a pre-aging and friction stir method(FSP)to enhance the low-temperature damping performance of the aluminum alloy and accommodate various service *** bonding between NiTi particles and the 1060Al matrix is well established after FSP,and no new phases are formed in the *** phasetransformation peak temperature of NiTip/1060Al composites gradually shifts to lower temperatures with increased aging temperature of NiTi *** room temperature,the 550℃-NiTip/1060Al composite exhibits superior damping performance,with an internal friction value 144%higher than that of the FSP-1060Al ***,at-91℃,the 650℃-NiTip/1060Al composite demonstrates better damping performance,with an internal friction value 158%higher than that of the FSP-1060Al *** NiTip/1060Al composites exhibit the internal friction peak of NiTi phase-transformation in the temperature range from-91℃to 60℃.This characteristic results in significantly better damping performance compared to the FSP-1060Al alloy and other high-damping aluminum matrix composites.

关键词： NiTi particle aluminum matrix composites phase transformation damping behavior friction stir processing

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An Improved Modulation Strategy for Single-phase Three-level Neutral-point-clamped Converter in Critical Conduction Mode

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 981-990页

作者： Ning Li Yujie Cao xiaokang Liu Yan Zhang Ruotong Wang Lin jiang xiao-Ping Zhang School of Electrical Engineering Xi’an University of TechnologyXi’anChina the Department of Electronics Information and BioengineeringPolitecnico di MilanoMilanItaly Xi’an Jiaotong University Xi’anChina the Department of Electrical Engineering and Electronics University of LiverpoolLiverpoolU.K. the Department of Electronic Electrical and Systems EngineeringUniversity of BirminghamBirminghamU.K.

Two-level totem-pole power factor correction(PFC)converters in critical conduction mode(CRM)suffer from the wide regulation range of switching ***,in highfrequency applications,the number of switching times increases,resulting in significant switching *** solve these issues,this paper proposes an improved modulation strategy for the single-phase three-level neutral-point-clamped(NPC)converter in CRM with *** optimizing the discharging strategy and switching state sequence,the switching frequency and its variation range have been efficiently *** detailed performance analysis is also presented regarding the switching frequency,the average switching times,and the effect of voltage gain.A 2 k W prototype is built to verify the effectiveness of the proposed modulation strategy and analysis *** with the totem-pole PFC converter,the switching frequency regulation range of the three-level PFC converter is reduced by 36.48%and the average switching times is reduced by 45.10%.The experimental result also shows a 1.2%higher efficiency for the three-level PFC converter in the full load range.

关键词： Critical conduction mode(CRM) on-board charger switching frequency range switching times power factor correction(PFC) three-level converter

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Promoted hydrogenation of CO2 to methanol over single-atom Cu sites with Na+-decorated microenvironment

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National Science Review 2024年第6期11卷 264-272页

作者： Li-Li Ling Xinyu Guan xiaoshuo Liu xiao-Mei Lei Zhongyuan Lin Hai-Long jiang Hefei National Research Center for Physical Sciences at the Microscale Department of Chemistry University of Science and Technology of China School of Energy and Power Engineering North China Electric Power University School of Energy and Environment Southeast University

Although single-atom Cu sites exhibit high efficiency in CO2hydrogenation to methanol,they are prone to forming Cu nanoparticles due to reduction and aggregation under reaction conditions,especially at high ***,single-atom Cu sites stabilized by adjacent Na+ions have been successfully constructed within a metal-organic framework（MOF）-based catalyst,namely *** is found that the electrostatic interaction between the Na+and Hδ-species plays a pivotal role in upholding the atomic dispersion of Cu in MOF-808-NaCu during CO2hydrogenation,even at temperatures of up to 275℃.This exceptional stabilization effect endows the catalyst with excellent activity(306 g·kgcat-1·h-1),high selectivity to methanol（93%） and long-term stability at elevated reaction temperatures,far surpassing the counterpart in the absence of Na+（denoted as MOF-808-Cu）.This work develops an effective strategy for the fabrication of stable single-atom sites for advanced catalysis by creating an alkali-decorated microenvironment in close proximity.

关键词： single-atom sites metal–organic framework CO2 hydrogenation heterogeneous catalysis alkali-metal decoration

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Advanced Materials for NH_(3)Capture:Interaction Sites and Transport Pathways

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Nano-Micro Letters 2024年第11期16卷 119-155页

作者： Hai‑Yan jiang Zao‑ming Wang Xue‑Qi Sun Shao‑Juan Zeng Yang‑Yang Guo Lu Bai ming‑Shui Yao Xiang‑Ping Zhang Key Laboratory of Green Process and Engineering State Key Laboratory of Mesoscience and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190People’s Republic of China School of Future Technology University of Chinese Academy of SciencesBeijing 100049People’s Republic of China China University of Petroleum Beijing 102249People’s Republic of China Institute for Integrated Cell‑Material Sciences(iCeMS) Kyoto UniversitySakyo‑KuYoshidaKyoto 606‑8501Japan

Ammonia(NH3)is a carbon-free,hydrogen-rich chemical related to global food safety,clean energy,and environmental *** an essential technology for meeting the requirements raised by such issues,NH3 capture has been intensively explored by researchers in both fundamental and applied *** four typical methods used are(1)solvent absorption by ionic liquids and their derivatives,(2)adsorption by porous solids,(3)abadsorption by porous liquids,and(4)membrane *** in the development of advanced materials for NH3 capture,we conducted a coherent review of the design of different materials,mainly in the past 5 years,their interactions with NH3 molecules and construction of transport pathways,as well as the structure–property relationship,with specific examples ***,the challenges in current research and future worthwhile directions for NH3 capture materials are proposed.

关键词： Ammonia capture Solvents Porous solids Porous liquids Membranes

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Heparin is an effective treatment for preventing liver failure after hepatectomy

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World Journal of Gastroenterology 2024年第22期30卷 2881-2892页

作者： Zhi-Ying Xu Min Peng ming-ming Fan Qi-Fei Zou Yi-Ran Li Dong jiang Hepatic Surgery IV Shanghai Eastern Hepatobiliary Surgery HospitalThe Third Affiliated Hospital of Naval Medical UniversityShanghai 200433China Ultrasound Diagnosis PLA Naval Medical CenterShanghai 200437China Department of Ultrasound Eastern Hepatobiliary Surgery HospitalThe Third Affiliated Hospital of Naval Medical UniversityShanghai 200433China

BACKGROUND Posthepatectomy liver failure(PHLF)is one of the most important causes of death following liver ***,an established anticoagulant,can protect liver function through a number of mechanisms,and thus,prevent liver *** To look at the safety and efficacy of heparin in preventing hepatic dysfunction after *** The data was extracted from Multiparameter Intelligent Monitoring in Intensive Care III(MIMIC-III)v1.4 pinpointed patients who had undergone hepatectomy for liver cancer,subdividing them into two cohorts:Those who were injected with heparin and those who were *** statistical evaluations used were unpaired ttests,Mann-Whitney U tests,chi-square tests,and Fisher’s exact tests to assess the effect of heparin administration on PHLF,duration of intensive care unit(ICU)stay,need for mechanical ventilation,use of continuous renal replacement therapy(CRRT),incidence of hypoxemia,development of acute kidney injury,and ICU *** regression was utilized to analyze the factors related to PHLF,with propensity score matching(PSM)aiming to balance the preoperative disparities between the two *** In this study,1388 patients who underwent liver cancer hepatectomy were *** yielded 213 matched pairs from the heparin-treated and control *** univariate analyses indicated that heparin potentially reduces the risk of PHLF in both matched and unmatched *** analysis in the matched cohorts confirmed a significant association,with heparin reducing the risk of PHLF(odds ratio:0.518;95%confidence interval:0.295-0.910;P=0.022).Additionally,heparin treatment correlated with improved short-term postoperative outcomes such as reduced ICU stay durations,diminished requirements for respiratory support and CRRT,and lower incidences of hypoxemia and ICU *** Liver failure is an important hazard following hepatic *** ICU care heparin administration has been proved to decr

关键词： Liver resection Posthepatectomy liver failure Prophylactic treatment Heparin Prognosis of hepatectomy

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培育我国农村保险市场的思考

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乡镇经济 2006年第8期22卷 43-45页

作者：蒋晓明安徽林业职业技术学院安徽合肥230031

全面建设小康社会,构建和谐社会,建设社会主义新农村,农村保险市场的加快发展将为其提供保障和支持。因此,本文对我国农村保险市场的现状、影响因素等方面进行剖析,指出了发展我国农村保险市场的思路。

关键词：农村保险市场风险

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