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Petroleum Science 2022年第6期19卷 3046-3058页

作者： En-bin Liu Yong peng shan-bi peng bin Yu Qi-Kun Chen Petroleum Engineering School Southwest Petroleum UniversityChengdu610500China School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengdu610500China China Petroleum Pipeline Engineering Corporation Hebei065000China School of Engineering Cardiff UniversityCardiffCF243AAUK

In order to reduce the carbon emissions of natural gas pipelines,based on the background of different energy structures,this paper proposes a general low carbon and low consumption operation model of natural gas pipelines,which is used to fine calculate the carbon emissions and energy consumption of natural gas *** this paper,an improved particle swarm optimization(NHPSO-JTVAC)algorithm is used to solve the model and the optimal scheduling scheme is *** a parallel pipeline located in western China as an example,the case is *** results show that after optimization,under the existing energy types,the pipeline system can reduce 31.14%of carbon emissions,and after introducing part of new energy,the pipeline system can reduce 34.02%of carbon emissions,but the energy consumption has increased.

关键词： Natural gas Pipeline optimization NHPSO-JTVAC algorithm Carbon emission New energy

Experimental and numerical simulation study on the erosion behavior of the elbow of gathering pipeline in shale gas field

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Petroleum Science 2024年第2期21卷 1257-1274页

作者： En-bin Liu Shen Huang Ding-Chao Tian Lai-Min Shi shan-bi peng He Zheng Petroleum Engineering School Southwest Petroleum UniversityChengdu 610500SichuanChina Chongqing Natural Gas Sales Center Natural Gas BranchSinopecChongqing400023China Zhejiang Zheneng Natural Gas Operation Co. Ltd.Hangzhou 310000ZhejiangChina School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu 610500SichuanChina Louisiana Tech Univ Trenchless Technol Ctr599 Dan Reneau DrRustonLA71270USA Southwest Oil and Gas Field Branch Natural Gas Research Institute Chengdu 610213SichuanChina

During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the Changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUENT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.

关键词： Shale gas Gas gathering pipeline Elbow Erosion CFD

Oscillatory Behavior of Solutions of General Third Order Mixed Neutral Difference Equations

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Acta Mathematicae Applicatae Sinica 2015年第2期31卷 467-474页

作者： bi-shan ZHANG School of Mathematics and Computing Science Guilin University of Electric and Technology

The objective of this paper is to study the oscillatory and asymptotic properties of the general mixed type third order neutral difference equation of the form △（aαn△2（xn＋ bnxn-τ1＋ cnxn＋τ2））＋ qnx^a n＋1-σ＋ pnx^βn＋1＋=σ2 0,where {an}, {bn}, {cn}, {qn} and {pn} are positive real sequences, both α and β are ratios of odd positive integers, τ1, τ2, σ1 and σ2 are positive integers. We establish some sufficient conditions which ensure all solutions are either oscillatory or converge to zero.

关键词： oscillation third order general mixed type neutral difference equation

Short-time Lv transform and its application for non-linear FM signal detection

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Journal of Systems Engineering and Electronics 2015年第6期26卷 1159-1168页

作者： shan Luo Xiumei Li Guoan bi School of Aeronautics and Astronautics University of Electronic Science and Technology of China School of Information Science and Engineering Hangzhou Normal University School of Electrical and Electronic Engineering Nanyang Technological University

A new time-frequency transform, known as short-time Lv transform （STLVT）, is proposed by applying the inverse Lv distribution to process consecutive segments of long data sequence. Compared with other time-frequency representations, the STLVT is able to achieve better energy concentration in the time-frequency domain for signals containing multiple linear and/or non-linear frequency modulated components. The merits of the STLVT are demonstrated in terms of the effects of window length and overlap length between adjacent segments on signal energy concentration in the time-frequency domain, and the required computational complexity. An application on the spectrum sensing for cognitive ratio （CR） by using a joint use of the STLVT and Hough transform （HT） is proposed and simulated.

关键词： Lv distribution time-frequency transform frequencymodulated signal spectrum sensing.

Enhanced Mechanics in Injection Molded Isotactic Polypropylene/Polypropylene Random Copolymer Blends via Introducing Network-like Crystal Structure

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Chinese Journal of Polymer Science 2016年第2期34卷 164-173页

作者： bi-qiang Jin Xin-peng Li Ming Jin Da-shan Mi Fei-fei Wang Chao Xia 张杰 State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan University

The crystallization behavior, rheological behavior, mechanical properties and microstructures of injection molded isotactic polypropylene （iPP）, polypropylene random copolymer （co-PP） and iPP/co-PP blends were investigated. Differential scanning calorimetry （DSC） and dynamic rheological analysis illustrated that iPP and co-PP were compatible in the blends and co-PP uniformly dispersed in the/PP phase. Polarizing optical microscope （POM） was adopted to observe the crystal size and morphology evolution. The results of mechanical properties and scanning electron microscopy （SEM） indicated that the crystal size of iPP in iPP/co-PP blends （10 wt% co-PP ＋ 90 wt% iPP and 30 wt% co-PP ＋ 70 wt% iPP） radically decreased after the incorporation of co-PP. During crystallization, the molecular chain segments of co-PP could penetrate iPP spherulites and form a network-like crystalline structure. The network-like crystal structure could effectively transmit stress and consume more energy to overcome intermolecular forces to resist stretching. In this way, the strength would improve to a certain degree. The impact fracture mechanism of iPP/co-PP blends is quasi ductile fracture by multiple crazes. Our work discovered that the blends containing 10 wt% and 30 wt% ofco-PP exhibited prominent toughness and reinforcement.

关键词： Network-like Morphology Toughness Polypropylene random copolymer.

Highly efficient green InP-based quantum dot light-emitting diodes regulated by inner alloyed shell component

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Light(Science & Applications) 2022年第7期11卷 1454-1463页

作者： peng Yu Sheng Cao Yuliang shan Yuhe bi Yaqi Hu Ruosheng Zeng bingsuo Zou Yunjun Wang Jialong Zhao School of Physical Science and Technology MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and MaterialsGuangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning 530004China Suzhou Xingshuo Nanotech Co. Ltd.(Mesolight)Suzhou 215123China

InP-based quantum dot light-emitting diodes(QLEDs),as less toxic than Cd-free and Pb-free optoelectronic devices,have become the most promising benign alternatives for the next generation lighting and ***,the development of green-emitting InP-based QLEDs still remains a great challenge to the environmental preparation of InP quantum dots(QDs)and superior device ***,we reported the highly efficient green-emitting InP-based QLEDs regulated by the inner alloyed shell *** on the environmental phosphorus tris(dimethylamino)phosphine((DMA)3P),we obtained highly efficient InP-based QDs with the narrowest full width at half maximum(~35 nm)and highest quantum yield(~97%)by inserting the gradient inner shell layer ZnSe_(x)S_(1-x)without further *** importantly,we concretely discussed the effect and physical mechanism of ZnSe_(x)S_(1-x)layer on the performance of QDs and QLEDs through the characterization of structure,luminescence,femtosecond transient absorption,and ultraviolet photoelectron *** demonstrated that the insert inner alloyed shell ZnSe_(x)S_(1-x)provided bifunctionality,which diminished the interface defects upon balancing the lattice mismatch and tailored the energy levels of InP-based QDs which could promote the balanced carrier *** resulting QLEDs applying the InP/ZnSe_(0.7)S_(0.3)/ZnS QDs as an emitter layer exhibited a maximum external quantum efficiency of 15.2%with the electroluminescence peak of 532 nm,which was almost the highest record of InP-based pure green-emitting *** results demonstrated the applicability and processability of inner shell component engineering in the preparation of high-quallity InP-based QLEDs.

关键词： diodes quantum component

Computations of unsteady transonic flow over airfoil at low Reynolds number

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航空动力学报 2013年第3期28卷 646-658页

作者： ZHU Hai-tao shan peng School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

Transonic flow over a thin airfoil at low Reynolds number was studied numerically by directly solving two-dimensional full Navier-Stokes equations through 5th order weighted essentially non-oscillatory(WENO) scheme without using any turbulence model.A series of distinguished unsteady phenomena for a thin 2-D transonic airfoil flow were *** to continuous adverse pressure gradient in the subsonic flow downstream of the sonic line,the unsteady separated boundary layer with main vortex and secondary vortex was developed at the rear of the *** the trailing edge,the vortex-shedding was characterized by periodical connection of the main vortex and secondary vortex on the other side of the *** unsteady separation and vortex-shedding occurred with the same *** the airfoil surface,the average pulse pressure related to the unsteady supersonic region was obviously smaller than that related to the vortex-shedding at the trailing *** the attack angle increasing from 0°to 2°,the frequency of vortex-shedding decreases about 4.2%.At last,the turbulence intensity and many second-order statistics in the wake region were investigated.

关键词： transonic flow unsteady flow direct numerical simulation(DNS) unsteady separation airfoil vortex-shedding

Two 3-D multi-cascade co-design inverse methods based on streamline curvature approach and Clebsch formulation for single-stage centrifugal compressors

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航空动力学报 2013年第7期28卷 1526-1538页

作者： TIAN Xiao-pei shan peng School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Two strategies extended the single-cascade methods from a compressible three-dimensional inverse method for radial and mixed flow turbomachines to two three-dimensional multi-cascade co-design methods for single-stage centrifugal *** two three-dimensional methods and a typical quasi-threedimensional streamline curvature through-flow inverse method were employed to design the same subsonic high-speed single-stage centrifugal *** compressor performances were simulated by a commercial Reynolds averaged Navier-Stokes(RANS) equations *** studies show that two three-dimensional codesign methods are reasonable and *** was found that : firstly the blade camber angle designed by the three-dimensional methods was larger than that designed by the quasi-three-dimensional method;and secondly with regard to two three-dimensional methods with different boundary conditions,the co-design result differences between the diffusers were small,but those between the deswirlers were relatively large.

关键词： centrifugal compressor through-flow inverse method three-dimensional inverse problem streamline curvature approach Clebsch formulation multi-cascade co-design

In situ strength profiles along two adjacent vertical drillholes from digitalization of hydraulic rotary drilling

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第1期15卷 146-168页

作者： Xuefan Wang peng peng Zhigang shan Zhongqi Yue Department of Civil Engineering The University of Hong KongHong KongChina PowerChina Huadong Engineering Corporation Limited HangzhouChina

Drilling speed and associated analyses from factual field data of hydraulic rotary drilling have not been fully *** paper provides the reference and comparison for the utilization of drilling information from two adjacent vertical drillholes that were formed with the same hydraulic rotary drilling machine and *** analysis of original factual data is presented to obtain the constant drilling speed during net drilling *** to the factual data along two adjacent drillholes,the digitalization results respectively include 461 linear zones and 210 linear zones with their constant drilling speeds and associated drilling *** digitalization results can accurately present the spatial distributions and interface boundaries of drilled geomaterials and the results are consistent with the paralleled site *** weighted average drilling speeds from 2.335 m/min to 0.044 m/min represent 13 types of drilled geomaterials from soils to hard *** quantitative relation between drilling speed and strength property is *** digitalization results can statistically profile the basic strength quality grades of III to VI from soils to hard *** thickness distributions of four strength quality grades are presented for each individual type of geomaterials along two *** total,50.2%of geomaterials from drillhole A are grade IV and 57.4%of geomaterials from drillhole B are grade *** digitalization results can offer an accurate and cost-effective tool to quantitatively describe the spatial distribution and in situ strength profile of drilled geomaterials in the current drilling projects.

关键词： Drilling process monitoring(DPM) Hydraulic rotary coring process Constant drilling speed Coring-resistant strength

Ancestral developmental potentials in early bony fish contributed to vertebrate water-to-land transition

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Zoological Research 2021年第2期42卷 135-137页

作者： Xu-peng bi Guo-Jie Zhang BGI-Shenzhen ShenzhenGuangdong 518083China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Villum Center for biodiversity Genomics Section for Ecology and EvolutionDepartment of BiologyUniversity of CopenhagenCopenhagen 2100Denmark

The water-to-land transition was a major step in vertebrate evolution and eventually gave rise to the tetrapods, including amphibians, reptiles, birds, and mammals. The first land invasion of our fish ancestors is con... 详细信息

关键词： invasion al. transition