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Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： Wen-jing zhao jing Wang Zhong-Yang Qi hui-Qing Liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient

Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： jing-jing Guo Kai-Xiang Di Lie-hui Zhang Yu-Long zhao hui-Ying Tang Rui-Han Zhang Ye Tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

Minimally invasive maxillary sinus augmentation with simultaneous implantation on an elderly patient:A case report

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World Journal of Clinical Cases 2020年第24期8卷 6408-6417页

作者： Shi-hui Yang Wan-Qi Yu jing-Jie Zhang Zhe Zhou Jun-Yan Wang Rui-Ning Shi Yan-Min Zhou jing-hui zhao Fan-Rong Meng Department of Dental Implantology School and Hospital of StomatologyJilin UniversityChangchun 130021Jilin ProvinceChina Department of Stomatology Aviation General HospitalBeijing 100000China

BACKGROUND In this case study,a minimally invasive transalveolar approach using platelet-rich fibrin and bone substitute with simultaneous implantation was carried out in an elderly *** analyzed the cone-beam computed tomography(CBCT)findings to evaluate bone *** SUMMARY A 65-year-old female with no contraindications for dental implants and loss of maxillary bilateral molars is *** by CBCT showed the available vertical bone height in the bilateral posterior maxilla was 0.5-6.8 mm in the left and 2.8-6.5 mm in the *** patient underwent a transalveolar approach using platelet-rich fibrin and bone substitute with simulataneous placement of an implant 10 mm in *** months post-surgery,the implant showed excellent osseointegration with the bone ***,full-ceramic crowns were ***-up at 2 years demonstrated satisfactory *** Platelet-rich fibrin and bone substitute can be used to augment the maxillary sinus with a vertical bone height less than 4 mm.

关键词： Maxillary sinus augmentation Bone substitute Bone regeneration Plateletrich fibrin Internal sinus floor elevation Case report

Turbulence Modulations in the Boundary Layer of a Horizontal Particle-Laden Channel Flow

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Chinese Physics Letters 2010年第6期27卷 129-132页

作者： LI jing LIU zhao-hui WANG Han-Feng CHEN Sheng LIU Ya-Ming HAN Hai-Feng ZHENG Chu-Guang State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074

Turbulence modulations are experimentally investigated using particle image velocimetry （PIV） in the lower boundary layer of a fully developed horizontal channel flow. A simultaneous two-phase PIV measurement technique is adopted to acquire the turbulent statistics quantities and to examine the coherent structures in the near-wall region. Polythene beads with diameters of 60 μm are used as dispersed phases, and the PIV measurements have been performed at three mass loadings varying from 2.5 ×10^-4 to 5 × 10^-3. All the experiments are performed at a wall shear Reynolds number of Reτ = 430. The results show that the presence of the particles suppresses the coherent structures, with shorter streamwise extent of the quasistrearnwise structures, and then, the wall-normal velocity fluctuations and shear Reynolds stresses are both decreased in the near-core region. In addition, as a result of the particle wake, the turbulence intensity and shear Reynolds stress both increase in the vicinity of the wall. Due to the drag effects of the particles on the gas, the streamwise velocity gradients decrease in the outer region and increase in the viscous sublayer, meanwhile the thickness of the viscous sublayer also decreases. These results cause the peak values of the streamwise velocity fluctuations adjacent to the wall to increase, and the peak positions shift to the wall. This is the reason for decreasing the near-wall region and increasing the near-core region of the streamwise velocity fluctuations in appearance.

关键词： Reynolds stress Wakes Flow in channels Turbulence intensities Statistical analysis Drag

Decreased expression of Neurensin-2 correlates with poor prognosis in hepatocellular carcinoma

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World Journal of Gastroenterology 2009年第38期15卷 4844-4848页

作者： Hai-Qing Ma Xiao-Ting Liang jing-jing zhao hui Wang Jian-Cong Sun Yi-Bing Chen Ke Pan Jian-Chuan Xia Key Laboratory of Oncology in Southern China and Departmentof Experimental Research Sun Yat-sen University Cancer CenterGuangzhou 510060 Guangdong Province China

AIM： To investigate the expression of Neurensin-2 （NRSN2） in hepatocellular carcinoma （HCC） and its prognostic values in predicting survival. METHODS： The expression and prognostic significance of NRSN2 in HCC was examined by performing immunohistochemical analysis using a total of 110 HCC clinical tissue samples, and Western blotting analysis to further confirm the result. RESULTS： Decreased NRSN2 expression was shown in 70.9% cases. Loss of NRSN2 expression in HCC was significantly related to tumor size （P = 0.006）. Larger tumor size was related to negative expression of NRSN2. Patients showing negative NRSN2 expression had a significantly shorter overall survival than those with positive expression （P = 0.008）. Multivariate Cox regression analysis indicated that NRSN2 expression level was an independent factor of survival （P = 0.013）. Western blotting analysis further confirmed decreased expression of NRSN2 in tumor tissues compared with non-tumorous tissues. CONCLUSION： Our study indicated that NRSIV2 could be a tumor suppressor gene for HCC and a candidate biomarker for long-term survival in HCC.

关键词： Neurensin-2 Hepatocellular carcinoma Expression Immunohistochemical analysis Prognosis

Dual-filler reinforced PVDF-HFP based polymer electrolyte enabling high-safety design of lithium metal batteries

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Nano Research 2024年第6期17卷 5251-5260页

作者： Chang Fang Kangsheng Huang jing zhao Shiqi Tian hui Dou Xiaogang Zhang Jiangsu Key Laboratory of Electrochemical Energy Storage Technologies College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China

Despite the high energy density of lithium metal batteries(LMBs),their application in rechargeable batteries is still hampered due to insufficient ***,we present a novel flame-retardant solid-state electrolyte based on polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP)with nano SiO_(2)aerogel as an inert filler but Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)as an auxiliary component to enhance the ion *** introduction of SiO_(2)aerogels imparts the polymer electrolyte with exceptional thermal stability and flame ***,the interaction between hydroxyl groups of SiO_(2)particles and PVDF-HFP creates a strong cross-linking structure,enhancing the mechanical strength and stability of the ***,the presence of SiO_(2)aerogel and LLZTO facilitates the dissociation of lithium salts through Lewis acid-base interactions,resulting in a high ionic conductivity of 1.01×10^(−3)S·cm^(−1)and a wide electrochemical window of~5.0 V at room temperature for the prepared ***,the assembled Li|Li cell demonstrates the excellent resistance to lithium dendrite and runs stablly for over 1500 h at a current density of 0.25 mA·cm^(−2).Thus,we prepare a pouch cell with high safety,which can work normally after short-circuiting under the external folding and cutting.

关键词： polymer electrolyte SiO_(2)/Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)dual-filler non-flammable long cycle life lithium metal battery

Enhancing personalized exercise recommendation with student and exercise portraits

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Journal of Electronic Science and Technology 2024年第2期22卷 91-109页

作者： Wei-Wei Gao hui-Fang Ma Yan zhao jing Wang Quan-Hong Tian College of Computer Science and Engineering Northwest Normal UniversityLanzhou730070China Computer Center of Gansu Province Lanzhou730070China

The exercise recommendation system is emerging as a promising application in online learning scenarios,providing personalized recommendations to assist students with explicit learning *** solutions generally follow a collaborative filtering paradigm,while the implicit connections between students(exercises)have been largely *** this study,we aim to propose an exercise recommendation paradigm that can reveal the latent connections between student-student(exercise-exercise).Specifically,a new framework was proposed,namely personalized exercise recommendation with student and exercise portraits(PERP).It consists of three sequential and interdependent modules:Collaborative student exercise graph(CSEG)construction,joint random walk,and recommendation list ***,CSEG is created as a unified heterogeneous graph with students’response behaviors and student(exercise)***,a joint random walk to take full advantage of the spectral properties of nearly uncoupled Markov chains is performed on CSEG,which allows for full exploration of both similar exercises that students have finished and connections between students(exercises)with similar ***,we propose to optimize the recommendation list to obtain different exercise *** analyses of two public datasets,the results demonstrated that PERP can satisfy novelty,accuracy,and diversity.

关键词： Educational data mining Exercise recommend Joint random walk Nearly uncoupled Markov chains Optimization Personalized learning

Inter-layer interference for multi-layered tight gas reservoir in the absence and presence of movable water

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Petroleum Science 2024年第3期21卷 1751-1764页

作者： Tao Zhang Bin-Rui Wang Yu-Long zhao Lie-hui Zhang Xiang-Yang Qiao Lei Zhang jing-jing Guo Hung Vo Thanh National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu60500SichuanChina Shaanxi Yanchang Petroleum(Group)Corp.Ltd. Xian710075ShaanxiChina Waseda Research Institute for Science and Engineering Waseda UniversityTokyoJapan

Due to the dissimilarity among different producing layers,the influences of inter-layer interference on the production performance of a multi-layer gas reservoir are ***,systematic studies of inter-layer interference for tight gas reservoirs are really limited,especially for those reservoirs in the presence of *** this work,five types of possible inter-layer interferences,including both absence and presence of water,are identified for commingled production of tight gas ***,a series of reservoir-scale and pore-scale numerical simulations are conducted to quantify the degree of influence of each type of *** field evidence from the Yan'an tight gas reservoir(Ordos Basin,China)is found to support the simulation ***,suggestions are proposed to mitigate the potential inter-layer *** results indicate that,in the absence of water,commingled production is favorable in two situations:when there is a difference in physical properties and when there is a difference in the pressure system of each *** reservoirs with a multi-pressure system,the backflow phenomenon,which significantly influences the production performance,only occurs under extreme conditions(such as very low production rates or well shut-in periods).When water is introduced into the multi-layer system,inter-layer interference becomes nearly *** both the gas-rich layer and water-rich layer for commingled production is not desirable,as it can trigger water invasion from the water-rich layer into the gas-rich *** gas-rich layer might also be interfered with by water from the neighboring unperforated water-rich layer,where the water might break the barrier(eg weak joint surface,cement in fractures)between the two layers and migrate into the gas-rich ***,the gas-rich layer could possibly be interfered with by water that accumulates at the bottom of the wellbore due to gravitational diff

关键词： Tight gas Comingled production Interference Two-phase flow Water blocking

New pimarane diterpenoids with antibacterial activity from fungus Arthrinium ***03

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Chinese Journal of Natural Medicines 2024年第4期22卷 356-364页

作者： zhao Songfeng jing Ziwei Department of Pharmacy the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

A comprehensive chemical study of the endophytic fungus Arthrinium sp. ZS03, associated with Acorus tatarinowii Schott, yielded eleven pimarane diterpenoids (compounds 1–11), including seven novel compounds designated arthrinoids A–G (1–7). The determination of their structures and absolute configurations was achieved through extensive spectroscopic techniques, quantum chemical calculations of electronic circular dichroism (ECD), and single-crystal X-ray diffraction analysis. Furthermore, 7 demonstrated inhibitory activity against Klebsiella pneumoniae, comparable to the reference antibiotic amikacin, with a minimum inhibitory concentration (MIC) of 8 μg·mL^(−1).

关键词： Arthrinium sp.ZS03 Pimarane diterpenoids Structural elucidation Antibacterial activity