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Combined optical fiber interferometric sensors for the detection of acoustic emission

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Optoelectronics Letters 2008年第3期4卷 184-187页

作者： LIANG Yi-jun MU Lin-lin LIU jun-feng yu Xiao-tao College of science Harbin Engineering University Harbin 150001 China

A type of combined optical fiber interferometric acoustic emission sensor is proposed. The sensor can be independent on the laser source and make light interference by matching the lengths of two arms,so it can be used to monitor the health of large structure. Theoretical analyses indicate that the system can be equivalent to the Michelson interferometer with two optical fiber loop reflectors,and its sensitivity has been remarkably increased because of the decrease of the losses of light energy. PZT is powered by DC regulator to control the operating point of the system,so the system can accurately detect feeble vibration which is generated by ultrasonic waves propagating on the surface of solid. The amplitude and the frequency of feeble vibration signal are obtained by detecting the output light intensity of interferometer and using Fourier transform technique. The results indicate that the system can be used to detect the acoustic emission signals by the frequency characteristics.

关键词： Acoustic emissions Acoustics Electric network analysis Fiber optics Fibers Fourier transforms Geodetic satellites Interferometers Interferometry Lattice vibrations Light sources Michelson interferometers Optical fibers Optical in Acoustic emission sensors Acoustic Emission signals Fiber loop reflectors Fourier Frequency characteristics Interferometric sensors Laser sources Light energy Light intensities Operating points Optical Vibration signals

A robust viscoelastic surfactant tolerating 20% HCl up to 150℃ for oil well stimulation

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Petroleum Science 2024年第3期21卷 1865-1874页

作者： Ji Wang Ning Qi Hong-Yao Yin yu-jun feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065SichuanPR.China Tianfu Yongxing Laboratory New Theory and Technology of CO_(2) Capture Research CenterChengdu610065SichuanPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China

Viscoelastic surfactants(VES)are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well ***,the ceiling temperature of commercial VES cannot exceed 120℃in practical use because of the poor thermal stability and fragile molecular structure,hindering their implementation in hightemperature oil reservoirs,i.e.,≥150℃.Here we synthesized a novel C22-tailed diamine,N-erucaminopropyl-N,N-dimethylamine(EDPA),and examined comparatively its rheological behavior,assemblies morphology and molecular stability in 20 wt%HCl with a commercial VES,erucyl dimethyl amidopropyl betaine(EDAB).The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150℃.Rheological results showed that the 2.5 wt%EDPA—20 wt%HCl solution maintains stable viscosity of 90 m Pa s at 150℃for 60 min,while that of 2.0 wt%EDAB HCl solution is just 1 m Pa s under identical conditions.1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context,but the EDAB suffered from degradation due to the hydrolysis of the amide group,accounting for the poor heat-resistance and *** reaction rate of 2.5 wt%EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt%HCl solution at 150℃,underpinning the potential of EDPA to be used in the high-temperature reservoirs *** work improved the thermal tolerance of VES in highly concentrated HCl solution,paving a feasible way for the acidization of high-temperature reservoir environments(~150℃).

关键词： Viscoelastic surfactants Thermal stability Self-diverting acid Wormlike micelles Acidizing stimulation

Laparoscopic anatomical liver resection of segment 7 using a sandwich approach to the right hepatic vein (with video)

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 217-220页

作者： Song-feng yu Wei-Chen Zhang jun yu Department of Hepatobiliary and Pancreatic Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Full laparoscopic liver resection has been performed widely since it was introduced in the early *** has been expanded from initial for partial resection of the anterolateral segments to non-restriction of area of the liver[1–3].Anatomical liver resec-tion is considered to have potential superiority than non-anatomic resection in terms of tumor prognosis,thus it is more often rec-ommended in the treatment of hepatocellular carcinoma[4,5].Recently,laparoscopic segmental liver resection according to the Couinaud classification has been widely performed due to its ad-vantages in minimal invasiveness and tumor prognosis.

关键词： resection liver hepatic

Combination patterns of precipitation and its concentration degree determining the risk of dengue outbreaks in China

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Advances in Climate Change Research 2023年第5期14卷 768-777页

作者： yu-Rong WU Xiao-Wen WANG Liang ZHAO Bo LU jun-feng yu Ze-Hua LIU Yi SUN Wan-Nian LIANG Cun-Rui HUANG School of Public Health Sun Yat-sen UniversityGuangzhou 510006China Vanke School of Public Health Tsinghua UniversityBeijing 100084China Shanghai Typhoon Institute China Meteorological Administration&Shanghai Key Laboratory of Meteorology and HealthShanghai Meteorological ServiceShanghai 200030China Center for Public Health and Epidemic Preparedness&Response Peking UniversityBeijing 100871China The State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China National Climate Center China Meteorological AdministrationBeijing 100081China Institute of Healthy China Tsinghua UniversityBeijing 100084China

The amount and distribution of precipitation can determine dengue risk by affecting mosquito breeding;however,previous studies failed to incorporate this bivariate characteristic to examine dengue fever *** the present research,nationwide data on daily dengue cases in China between January 2005 and December 2020 were obtained,and the top 12 cities accounting for 78%of total cases were selected for *** patterns were quantified by weekly precipitation and precipitation concentration degree(PCD).On the basis of the combinations of both parameters,the exposure-response relationships of precipitation with dengue risk were established using generalised additive models,and the high-dengue-risk thresholds of precipitation patterns were further *** burden was assessed by calculating attributable dengue *** the same amount of precipitation,the dispersed precipitation in the pre-summer rainy season leads to a higher dengue risk in *** weekly precipitation of 100-150 mm and PCD of 0.2-0.4 constitute the highest risk scenario,and the average frequency of precipitation associated with dengue risk in 2013-2020 is 1.6 times higher than that in 2005-2012.A total of 3093 attributable dengue cases are *** 2005 to 2020,the amount of dispersed precipitation increased in southern and southwestern China and posed high dengue risks in central *** study has improved the understanding of the health impacts of irregular rainfall under climate *** approach to identifying thresholds provides information for early warning systems and helps reduce the risk of dengue transmission in the long run.

关键词： Climate change Precipitation pattern Precipitation concentration degree Dengue fever Mosquito-borne diseases

Approximate Synchronization of Multi-Agent Systems over Finite Fields

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Journal of Systems Science & Complexity 2024年第4期37卷 1561-1580页

作者： yu Miao feng jun-e XIA Jianwei FU Shihua SHEN Hao School of Mathematical Sciences Liaocheng UniversityLiaocheng 252059China School of Mathematics Shandong UniversityJinan 250100China School of Electrical and Information Engineering Anhui University of TechnologyMaanshan 243002China

In this paper,the approximate synchronization of leader-follower multiagent systems(MASs) over finite fields is studied in regard to local and global ***,the approximately synchronous state set(ASSS) is ***,combined with ASSS and transient periods,some criteria for the local and global approximate synchronization of systems are ***,the algorithms for calculating the maximum approximately synchronous basin(MASB) and the maximum control invariant set(MCIS) are ***,the global approximate synchronization of the system is achieved by designing the state feedback control,and a design algorithm of the controller using the truth matrix method is ***,the results of approximate synchronization are degenerated to complete ***,two examples are shown to demonstrate the results of this paper.

关键词： Approximate synchronization finite field multiagent system semi-tensor product state feedback control

Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： Hai-jun Li Ying-Quan Peng Wei Chao yu-feng Zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

Paeoniflorin,the Main Monomer Component of Paeonia lactiflora,Exhibits Anti-inflammatory Properties in Osteoarthritis Synovial Inflammation

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Chinese Journal of Integrative Medicine 2024年第5期30卷 433-442页

作者： CHEN Pu ZHOU jun RUAN An-min MA yu-feng WANG Qing-fu Department of Orthopaedic Surgery Beijing University of Chinese Medicine Third Affiliated HospitalBeijing 100029China Department of Orthopaedic Surgery Guangdong Provincial Hospital of Chinese MedicineGuangzhou 510120China Department of Orthopaedic Surgery Beijing Longfu HospitalBeijing 100010China

Objective:To explore the mechanism of paeoniflorin(PF)on osteoarthritis(OA)synovial inflammation from network pharmacology to experimental ***:Targets of OA were constructed by detecting the database of network database platforms(Therapeutic Target database,Drug Bank and Gene Cards),and the targets of PF were constructed by Pub Chem and Herbal Ingredients'Targets *** Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis of these co-targeted genes were conducted via Database for Annotation,Visualization,and Integrated Discovery(DAVID)database,and protein-protein interaction(PPI)networks were conducted via the search tool for the retrieval of interacting genes(STRING)*** counting kit-8(CCK-8)assay was performed to assess the potential toxicity of PF on human OA fibroblast-like synoviocytes(FLS),quantitative real-time polymerase chain reaction(q PCR),enzyme-linked immunosorbent assay(ELISA)and Western blot were used to verify the potential mechanism of PF in synovial ***:Twenty-six co-targeted genes were *** enrichment results showed that these co-targeted genes were most likely localized in the cytoplasm,and the biological processes mainly involved'cellular response to hypoxia''lipopolysaccharide(LPS)-mediated signaling pathway'and'positive regulation of gene expression'.KEGG pathway analysis indicated that these co-targeted genes may function through pathways associated with'hypoxia-inducible factor-1(HIF-1)signaling pathway'and'tumornecrosis factor(TNF)signaling pathway'.The PPI network showed that the top 3 hub genes were TP53,TNF,and *** docking results showed that PF was well docking with ***-8 showed no potential toxicity of 10,20 and 50μmol/L PF on human OA *** PF significantly decreased the expression levels of interleukin-1β,interleukin-6,TNF-αmatrix metalloproteinase 13(MMP13),and a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS5)and TNF

关键词： paeoniflorin osteoarthritis synovial inflammation tumor necrosis factor-α network pharmacology Paeonia lactiflora

Stability analysis of longwall top-coal caving face in extra-thick coal seams based on an innovative numerical hydraulic support model

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International Journal of Mining Science and Technology 2024年第4期34卷 491-505页

作者： jun Guo Wenbo Huang Guorui feng Jinwen Bai Lirong Li Zi Wang Luyang yu Xiaoze Wen Jie Zhang Wenming feng College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Shanxi Province for Mine Rock Strata Control and Disaster Prevention Taiyuan University of TechnologyTaiyuan 030024China Shanxi Coking Coal Group Co. Ltd.Taiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024China

The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining *** view of the fact that most of the existing numerical simulation methods construct virtual elements and stress servo control to approximately replace the hydraulic support problem,this paper establishes a new numerical model of hydraulic support with the same working characteristics as the actual hydraulic support by integrating numerical simulation software Rhino,Griddle and FLAC3D,which can realize the simulation of different working *** on this model,the influence mechanism of the supporting strength of hydraulic support on surrounding rock stress regulation and coal stability in front of the top coal caving face in extra thick coal seam were ***,under different support intensity,the abutment pressure of the bearing coal and the coal in front of it presents the “three-stage”evolution *** influence range of support intensity is 15%–30%.Secondly,1.5 MPa is the upper limit of impact that the support strength can have on the front coal failure ***,within a displacement range of 2.76 m from the coal wall,a support strength of1.5 MPa provides optimal control of the horizontal displacement of the coal.

关键词： Extremely thick coal seam Fully mechanized top coal caving Support strength Support-surrounding rock interaction

Chronic sleep deprivation induces alterations in DNA and RNA modifications by liquid chromatography-mass spectrometry analysis

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Chinese Chemical Letters 2024年第8期35卷 413-417页

作者： Tian feng yun-Ling Gao Di Hu Ke-yu yuan Shu-Yi Gu Yao-Hua Gu Si-yu yu jun Xiong yu-Qi feng Jie Wang Bi-feng yuan School of Public Health Research Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Department of Radiation and Medical Oncology Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences-Wuhan National Laboratory for OptoelectronicsWuhan 430071China University of Chinese Academy of Sciences Beijing 101408China Institute of Neuroscience and Brain Diseases Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyang 441000China Phase I Clinical Trial Laboratory Zhongnan Hospital of Wuhan UniversityWuhan 430071China

Sleep deprivation(SD)is a widespread issue that disrupts the lives of millions of *** effects ini-tiate as changes within neurons,specifically at the DNA and RNA level,leading to disruptions in neuronal plasticity and the dysregulation of various cognitive functions,such as learning and *** acid epigenetic modifications that could regulate gene expression have been reported to play crucial roles in this ***,there is a lack of comprehensive research on the correlation of SD with nucleic acid epigenetic *** the current study,we aimed to systematically investigate the landscape of modifications in DNA as well as in small RNA molecules across multiple tissues,including the heart,liver,kidney,lung,hippocampus,and spleen,in response to chronic sleep deprivation(CSD).Using liquid chromatography-tandem mass spectrometry(LC-MS/MS)analysis,we characterized the dynamic changes in DNA and RNA modification profiles in different tissues of mice under CSD ***,we ob-served a significant decrease in the level of 5-methylcytosine(5mC)and a significant increase in the level of 5-hydroxymethylcytosine(5hmC)in the kidney in CSD *** RNA modifications,we observed an overall increased trend for most of these significantly changed modifications across six tis-sues in CSD *** study sheds light on the significance of DNA and RNA modifications as crucial epigenetic markers in the context of CSD-induced stress.

关键词： Sleep deprivation Epigenetics Mass spectrometry DNA modification RNA modification Small RNA