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Reliability analysis of carbon fiber rod-reinforced umbilical cable under tension using an improved sampling method

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Petroleum Science 2024年第4期21卷 2769-2778页

作者： Yu Zhang hong-Yu Zhang Ran Xia si-Ao Jiang Fang Wang College of Safety and Ocean Engineering China University of Petroleum China Academy of Aerospace Aerodynamics China Aerospace Science and Technology Group College of Engineering Science and Technology Shanghai Ocean University

The umbilical cable is a vital component of subsea production systems that provide power, chemical agents, control signals et al., and its requirement for reliability is exceedingly high. However, as the umbilical cable is a composite structure comprising multiple functional units, the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency. In this paper, the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed. The global dynamic analytical model is first established to determine the maximum tension load, then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM). Based on the mechanical analytical model, the reliability of umbilical cable under tension load is studied using response surface method(RSM) and Monte Carlo method. During the calculation process, a new tangent plane sampling method to calculate the response surface function(RSF) is proposed in this paper, which could make sampling points faster come close to the RSF curve, and it is proved that the calculation efficiency increases about 33% comparing with traditional method.

关键词： Umbilical cable Carbon fiber rod Failure analysis Response surface method Reliability

Ultrasound blood flow characteristics changes in fetal umbilical artery thrombosis:A retrospective analysis

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World Journal of Clinical Cases 2024年第2期12卷 240-248页

作者： si-Jie hong Li-Wei hong Xiao-Qin He Xiao-hong Zhong Department of Ultrasound Women and Children's HospitalSchool of MedicineXiamen UniversityXiamen 361000Fujian ProvinceChina Ministry of Science and Education Women and Children's HospitalSchool of MedicineXiamen UniversityXiamen 361000Fujian ProvinceChina

BACKGROUND Umbilical artery thrombosis(UAT)is extremely uncommon and leads to adverse perinatal *** of blood in pregnant women is suspected to be an important risk for *** is an effective way to detect *** mother can monitor her own fetal health using ultrasound,which enables her to take preventative action in case of *** To investigate ultrasonic blood signal after UAT in the umbilical artery,and evaluate the relationship between hypercoagulability and *** We described a case of a newly formed UAT with markedly altered ultrasonic indices of umbilical artery blood flow,and retrospectively studied it with 18 UAT patients confirmed by histopathology from October 2019 and March 2023 in Xiamen Women and Children's ***’information was collected from medical archives,including maternal clinical data,neonatal outcomes,pathological findings and ultrasonic indices of umbilical artery blood flow,such as systolic-diastolic duration ratio(S/D),resistance index(RI),pulsatility index(PI)and peak systolic velocity(PSV).Ultrasound and coagulation indices were analyzed with matched samples t-test and Wilcoxon rank sum test using the statistical packages in R(version 4.2.1)including car(version 3.1-0)and stats(version 4.2.1),and visualized by ggplot2 package(version 3.3.6).RESULTS A patient with normal findings in second and third-trimester routine ultrasound scan developed UAT with severe changes in ultrasonic indices of umbilical artery blood flow(within 2.5th of reference ranges)in a short period of *** analysis of umbilical artery blood flow ultrasound indices for 19 patients with UAT showed that the decrease in S/D,RI,and PI and increase of PSV during the disease process was greater than that of *** 18 patients delivered in our hospital showed characteristic manifestations of UAT on histological examination after delivery,most of which(16/18)showed umbilical cord abnormalities,with 1

关键词： Umbilical artery thrombosis Obstetric ultrasonography Peak systolic velocity Hypercoagulation Umbilical cord abnormalities Fetus

Clinical efficacy of laparoscopic cholecystectomy combined with endoscopic papillary balloon dilation in treatment of gallbladder stones with common bile duct stones: A retrospective study

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1700-1708页

作者： hong-Dan Liu Qi Zhang Wen-si Xu Shuang Jin Department of Gastroenterology The Third Affiliated Hospital of Qiqihar Medical UniversityQiqihar 161000Heilongjiang ProvinceChina

BACKGROUND The incidence of cholelithiasis has been on the rise in recent years,but the choice of procedure is *** To investigate the efficacy of laparoscopic cholecystectomy(LC)combined with endoscopic papillary balloon dilation(EPBD)in patients with gallbladder stones(GS)with common bile duct stones(CBDS).METHODS The clinical data of 102 patients with GS combined with CBDS were selected for retrospective analysis and divided into either an LC+EPBD group(n=50)or an LC+endoscopic sphincterotomy(EST)group(n=52)according to surgical ***-related indexes,postoperative recovery,postoperative complications,and expression levels of inflammatory response indexes were compared between the two *** Total surgical time,stone free rate,rate of conversion to laparotomy,and successful stone extraction rate did not differ significantly between the LC+EPBD group and LC+EST *** hemorrhage,time to ambulation,and length of hospitalization in the LC+EPBD group were lower than those of the LC+EST group(Psion levels of interleukin-6,tumor necrosis factor-α,high-sensitivity Creactive protein,and procalcitonin were lower in the LC+EPBD group than in the LC+EST group(Psion levels of aspartate transaminase,alanine transaminase,and total bilirubin were lower in the LC+EPBD group than in the LC+EST group(PsiON LC combined with EPBD and LC combined with EST are both effective procedures for the treatment of GS with CBDS,in which LC combined with EPBD is beneficial to shorten the patient’s hospitalization time,reduce the magnitude of elevated inflammatory response indexes,and promote postoperative recovery.

关键词： Gallbladder stone Common bile duct stone Endoscopic papillary balloon dilation Laparoscopic cholecystectomy Endoscopic sphincterotomy

Operando measurement of lattice deformation profiles of synchrotron radiation monochromator

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Nuclear Science and Techniques 2024年第7期35卷 8-19页

作者： Yue Zhang Zhong-Liang Li Shang-Yu si Lian Xue hong-Xin Luo Xiao-Wei Zhang Jun Hu Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201204China ShanghaiTech University Shanghai201210China University of the Chinese Academy of Sciences Beijing100049China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing100049China

This study presents a new method for characterizing the thermal lattice deformation of a monochromator with high precision under service conditions and first reports the operando measurements of nanoscale thermal lattice deformation on a double-crystal monochromator at different incident *** nanoscale thermal lattice deformation of the monochromator first crystal was obtained by analyzing the intensity of the distorted DuMond *** diagrams of the 333 diffraction index,sensitive to lattice deformation,were obtained directly using a 2D detector and an analyzer crystal orthogonal to the *** increasing incident power and power density,the maximum height of the lattice deformation increased from 3.2 to 18.5 nm,and the deformation coefficient of the maximum height increased from 1.1 to 3.2 nm/*** maximum relative standard deviation was 4.2%,and the maximum standard deviation was 0.1 *** on the measured thermal deformations,the flux saturation phenomenon and critical point for the linear operation of the monochromator were predicted with increasing incident *** study provides a simple solution to the problem of the lower precision of synchrotron radiation monochromator characterizations compared to simulations.

关键词： Synchrotron radiation Monochromator Lattice deformation X-ray dynamic diffraction

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Prediction and quantification of effective gas source rocks in a lacustrine basin: Western Depression in the Liaohe Subbasin, China

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Petroleum Science 2024年第4期21卷 2218-2239页

作者： si-Bo Yang Mei-Jun Li hong Xiao Fang-Zheng Wang Guo-Gang Cai Shuang-Quan Huang State Key Laboratory of Petroleum Resources and Prospecting College of Geosciences China University of Petroleum China University of Petroleum-Beijing at Karamay College of Petroleum Research Institute of Petroleum Exploration and Development Liaohe Oilfield Company PetroChina

Due to limited data on the geochemical properties of natural gas, estimations are needed for the effective gas source rock in evaluating gas potential. However, the pronounced heterogeneity of mudstones in lacustrine successions complicates the prediction of the presence and geochemical characteristics of gas source rocks. In this paper, the Liaohe Subbasin of Northeast China is used as an example to construct a practical methodology for locating effective gas source rocks in typical lacustrine basins. Three types of gas source rocks, microbial, oil-type, and coal-type, were distinguished according to the different genetic types of their natural gas. A practical three-dimensional geological model was developed, refined, and applied to determine the spatial distribution of the mudstones in the Western Depression of the Liaohe Subbasin and to describe the geochemical characteristics(the abundance, type, and maturation levels of the organic matter). Application of the model in the subbasin indicates that the sedimentary facies have led to heterogeneity in the mudstones, particularly with respect to organic matter types. The effective gas source rock model constructed for the Western Depression shows that the upper sequence(SQ2) of the Fourth member(Mbr 4) of the Eocene Shahejie Formation(Fm) and the lower and middle sequences(SQ3 and SQ4) of the Third member(Mbr 3) form the principal gas-generating interval. The total volume of effective gas source rocks is estimated to be 586 km3. The effective microbial, oil-type, and coal-type gas source rocks are primarily found in the shallow western slope, the central sags, and the eastern slope of the Western Depression, respectively. This study provides a practical approach for more accurately identifying the occurrence and geochemical characteristics of effective natural gas source rocks, enabling a precise quantitative estimation of natural gas reserves.

关键词： Effective gas source rock 3D geological modeling Spatial distribution Geochemical characteristics Lacustrine rift basin

Nitrogen addition increased resistance of resident plant community to Solidago canadensis invasion by altering allelopathic effect

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JOURNAL OF PLANT ECOLOGY 2024年第2期17卷 110-121页

作者： Cai, Jing-Fang Sun, Kai Li, Lin A, si-Ha Shen, Yi-Luan Li, hong-Li Beijing Forestry Univ Sch Ecol & Nat Conservat Beijing 100083 Peoples R China Beijing Forestry Univ Key Lab Ecol Protect Yellow River Basin Natl Forestry & Grassland Adm Beijing 100083 Peoples R China

Allelopathy plays an important role in the interaction between invasive and resident plants. Atmospheric nitrogen (N) deposition has become a global problem, but it is unclear whether N enrichment affects the interaction between invasive and resident plants by affecting their allelopathy. Thus, we performed a greenhouse experiment in which the resident plant community was grown under two levels of invasion by S. canadensis (invasion vs. no invasion) and fully crossed with two levels of allelopathy (with or without adding activated carbon) and two levels of N addition (with or without). The resident plant communities were constructed with eight herbaceous species that often co-occur with S. canadensis. The results showed that both allelopathy of S. canadensis and the resident plants had obvious positive effects on their own growth. Nitrogen addition had more obvious positive effects on the resident plants under invasion than those that were not invaded. Moreover, N addition also altered the allelopathy of resident plants. Specifically, N addition improved the allelopathy of resident plants when they were invaded but decreased the allelopathy of resident plants when they grew alone. Although nitrogen addition had no obvious effect on S. canadensis, it reduced the allelopathy of S. canadensis. These results suggest that N addition could improve the resistance of resident plants to invasion by improving the allelopathy of resident plants and reducing the allelopathy of S. canadensis. These findings provide a scientific basis to manage and control the S. canadensis invasion.

关键词： allelochemicals biological invasion nutrient input nitrogen addition resident plants Solidago canadensis DEPOsiTION COMPETITION DIVERsiTY EVOLUTION RESPONSES SUCCESS

Tidal effects based on a GUP-induced effective metric

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Communications in Theoretical Physics 2024年第9期76卷 63-72页

作者： Soon-Tae hong Yong-Wan Kim Young-Jai park Center for Quantum Spacetime and Department of Physics Sogang UniversitySeoul 04107Republic of Korea Department of Physics and Research Institute of Physics and Chemistry Jeonbuk National UniversityJeonju 54896Republic of Korea Department of Physics Sogang UniversitySeoul 04107Republic of Korea

In this paper,we study tidal forces in the Schwarzschild black hole,whose metric explicitly includes a generalized uncertainty principle(GUP)*** also investigate interesting features of the geodesic equations and tidal effects that are dependent on the GUP parameterαrelated to a minimum ***,by solving the geodesic deviation equations explicitly with appropriate boundary conditions,we show thatαin the effective metric affects both the radial and angular components of the geodesic equation,particularly near the singularities.

关键词： generalized uncertainty principle geodesic deviation equation effective metric

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N, P co-doped 3D porous carbon with self-assembled morphological control via template-free method for potassiumion battery anodes

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Rare Metals 2024年第9期43卷 4243-4252页

作者： Jeehoon Yu Dae Kyom Kim hong Geun Oh Seung-Keun park Youngjae Yoo Department of Advanced Materials Engineering Chung-Ang University

The larger ionic radius of potassium ions than that of lithium ions significantly limits the accomplishment of rapid diffusion kinetics in graphite electrodes for potassium-ion batteries （PIBs）,resulting in comparatively poor rate performance and cycle ***,we report a high-rate performance and cycling stability amorphous carbon electrode achieved through nitrogen and phosphorous *** as-prepared N,P co-doped carbon electrodes have distinct 3D structures with large surface areas,hierarchical pore architectures,and increased interlayer spaces resulting from the direct pyrolysis of supramolecular self-assembled aggregates without *** obtained electrode N3P1 exhibits a reversible specific capacity of 258 m Ah·g-1at a current density of 0.1A·g-1and a good long-term cycle performance (96.1%capacity retention after 800 cycles at 0.5 A·g-1).Kinetic investigations show that the N3P1 electrode with the welldeveloped porous structure and large number of surface defects exhibits capacitive-driven behavior at all scan rates,which may be attributed by N and P ***-situ transmission electron microscopy analyses in the fully discharged and charged states demonstrate structural stability and reversibility owing to the expanded interlayer *** suggested synthesis approach is simple and effective for producing heteroatom-doped carbon materials for PIBs and other advanced electrochemical energy storage materials.

关键词： 3D porous structures Amorphous carbons Nitrogen and phosphorous co-doping Potassium-ion batteries

Effects of heat treatment on microstructures and properties of a heterostructured alloy with dissimilar components fabricated by WAAM

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Rare Metals 2024年第9期43卷 4441-4461页

作者： Ming-Cai Pan Jun-Qiang Xu Yong Peng Ning-Ning Liang si Lan Qi Zhou Ke-hong Wang School of Materials Science and Engineering Nanjing University of Science and Technology Key Laboratory of Controlled Arc Intelligent Additive Manufacturing Technology

Heat treatment significantly influences homogeneous material microstructures and mechanical properties, which can be improved by an optimal heat treatment process. However, heat treatment application to heterogeneous materials presents significant challenges due to compositional and microstructural heterogeneities. Herein,a laminated heterostructured alloy comprising alternating316L stainless steel（SS） and 18Ni300 maraging steel（MS）layers fabricated using wire and arc additive manufacturing was investigated. A solution treatment was applied at900 °C for 0.5 h. Subsequently, the solution-treated and asfabricated（AF） samples were aged at 500 °C for 4 h; these samples were denoted SA and AT, respectively. The AT phase compositions and orientations were similar to those of AF. The SA 316L SS layer resembled that of AF, but the SA 18Ni300 MS layers exhibited a reduced austenite phase fraction and refined grain size, attributable to solid-state transformation. In the AT sample, aging induced the formation of nanoscale acicular ω phase and ellipsoidal Ni3Ti,Fe2Mo, and X precipitates in the 18Ni300 MS ***, the SA precipitates contained acicular Fe Ni2and ellipsoidal ω, Ni3Ti, and X precipitates, and their fractions were lower than those in AT precipitates. The18Ni300 MS layer microhardness in the heat-treated samples increased due to nanoprecipitation, but the 316L SS layer microhardness resembled that of AF. The AT and SA ultimate tensile strengths increased to（1360 ± 50） and（1473 ± 41） MPa, respectively, attributable to precipitation strengthening. The SA 316L SS layer exhibited a high stress-induced martensite fraction, enhancing the ductility of heated samples.

关键词： Heat treatment Laminated heterostructured alloy Mechanical property Microstructure Wire and arc additive manufacturing