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Influence of Wellbore Trajectory on Pressure Drop and Fluid Discharge

Fluid Dynamics & Materials Processing 2023年第8期19卷 2053-2066页

作者： Ruidong Wu Guowei Wang zhixing yang Ruiquan Liao yang Cheng Shanghai Branch of CNOOC(China)Co. Ltd.Shanghai200335 CNPC Key Laboratory of Oil and Gas Productions on yangtze University Jingzhou434023China Petrochina Multiphase Flow Laboratory of Gas Lift Innovation Center Wuhan430100China Petroleum Engineering College of yangtze University Wuhan430100China

An experimental analysis has been conducted to study the process of fluid accumulation for different borehole trajectories.More specifically,five heel angles have been experimentally realized to simulate the borehole trajectory of the sloping section of the formation.The fluid-carrying capacity,pressure drop and fluid discharge volatility have been investigated for these conditions and,accordingly,the relationship between heel angle and wellbore pressure drop fluid-carrying capacity has been determined.The results show that while the reasonable roll angle can increase the pressure loss in the wellbore,it is beneficial to drainage.In terms of pressure loss and liquid-carrying capacity,when the heeling angle is 50°,the latter is increased while the former becomes very high,which indicates that when drilling and completing wells on site,a 50°roll angle should be avoided.It is found that the main reason for the increase of the total pressure drop in the wellbore is the increase of the local pressure loss in the inclined section.From the perspective of drainage stability,when there is heeling in the inclined section of the horizontal well,the fluctuation of the wellbore drainage tends to be enhanced.Through the comparison of the Beggs-Brill(B-B)and Mukherjee-Brill liquid holdup methods,it is found that B-B method better predicts liquid holdup.A new method for calculating the pressure drop in the inclined section in the presence of lateral inclination is obtained by taking into account the pressure drop in the curved section.Through comparison with experimental data,it is found that the error is within 20%,and the prediction accuracy is high.

关键词： Horizontal well slant section heel angle pressure drop drainage quantity

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Identifying QTL and candidate genes for prolificacy in maize

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The Crop Journal 2023年第2期11卷 531-539页

作者： Min Wang Renyu Zhang yangzi Zhao Jieyuan Yao Weiya Li zhixing yang Fei Sun Xiaohong yang State Key Laboratory of Plant Physiology and Biochemistry and National Maize Improvement Center of China China Agricultural UniversityBeijing 100193China Institute of Advanced Agricultural Technology Qilu Normal UniversityJinan 250200ShandongChina

In maize,prolificacy,the number of ears per plant,is a trait of interest to maize breeders for breeding high grain-yielding cultivars or specialty corn,as well as being a model trait for decoding the molecular mechanism of maize evolution.Its genetic basis remains largely unknown.We identified a stable quantitative trait locus,qEN7,for ear number on chromosome 7 in both F2 and F2:3 populations derived from a single cross between the nonprolific inbred line Mo17 and the prolific inbred line LAN404 derived from the landrace PI217404.qEN7 explained 10.7%-11.9%of phenotypic variation,and the LAN404 allele at this locus was associated with an increase of around one ear per plant.qEN7 was confined by fine-mapping to a 0.56-Mb region containing eight annotated genes.Analysis of selection,gene expression patterns in various maize tissues,and sequence polymorphisms between the two parental lines suggested that Zm00001d020683,which encodes a putative INDETERMINATE DOMAIN(IDD)transcription factor,is the most likely candidate gene underlying qEN7.Zm00001d020683 is expressed mainly in the vegetative meristem,immature ears,and internodes and has undergone selection during maize improvement.The identification of qEN7 and the prediction of its candidate gene sheds some light on the evolution of maize ear number and provides a novel resource for breeding of multi-ear maize cultivars.

关键词： Prolificacy QTL mapping Fine mapping Selection analysis Maize

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二代高温超导带材失超特性研究

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电工技术学报 2024年第1期39卷 110-120,153页

作者：杨志星任丽徐颖段璞李鑫强电磁工程与新技术国家重点实验室(华中科技大学电气与电子工程学院) 武汉430074

高温超导带材失超会降低其通流能力,从而影响高温超导装置的运行稳定性。目前,高温超导带材失超仿真模型多为二维计算模型,无法准确模拟其失超过程中的电磁热行为。该文采用有限元方法对二代高温超导带材失超特性进行多物理场耦合分析... 详细信息

高温超导带材失超会降低其通流能力,从而影响高温超导装置的运行稳定性。目前,高温超导带材失超仿真模型多为二维计算模型,无法准确模拟其失超过程中的电磁热行为。该文采用有限元方法对二代高温超导带材失超特性进行多物理场耦合分析。在三维直角坐标系下,以磁场强度矢量为求解变量,建立了二代高温超导带材失超演化电磁热仿真模型,研究了二代高温超导带材长度方向与宽度方向在不同热扰动工况下的电磁热特性及其演化过程,分析了高温超导带材过电流失超过程中的各层分流状况与超导层电阻率变化行为,区分了不同类型的过电流失超行为,并提出了高温超导带材过电流冲击失超的电阻率判据。

关键词：二代高温超导带材失超特性有限元电磁热耦合

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UDI在妇幼专科医院医用耗材管理中的应用分析

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中国医药导刊 2024年第5期26卷 494-497页

作者：汤超洋杨智星四川大学华西第二医院四川成都610041

医疗器械唯一标识(UDI)是医疗器械产品的电子身份证,有助于医疗器械耗材的标准化和规范化管理。医用耗材的申请、采购、配送和使用是医院规范化管理的重要内容,也是医院实现精细化管理的重点。医用耗材实施UDI管理,通过信息化手段准确... 详细信息

医疗器械唯一标识(UDI)是医疗器械产品的电子身份证,有助于医疗器械耗材的标准化和规范化管理。医用耗材的申请、采购、配送和使用是医院规范化管理的重要内容,也是医院实现精细化管理的重点。医用耗材实施UDI管理,通过信息化手段准确识别和智能管理,可提升医疗机构的综合管理能力。本研究按照国家药品监督管理局工作要求,以某三甲妇幼专科医院实施UDI管理医用耗材的智能建设实践为基础,结合医用耗材供应链管理要求,充分利用医院现有的信息系统资源,辅以智能化管理设施、设备,实现院内医用耗材编码与UDI编码、医保编码的关联,实现医用耗材管理信息化、智能化,补充完善卫生行政主管部门对医疗机构、医务人员、医疗行为的监管要素。本研究认为,我院医用耗材实施UDI管理,虽然存在UDI数据库产品不完整、医院物资管理系统与UDI数据库难以对接、“三医联动”信息化管理难度增加等问题,但UDI是实现所有医用耗材的精细化、标准化、科学化管理的基础,能保证医用耗材的安全性、有效性,优化财务管理和患者自助查询,实现了医用耗材的财务精准结算、财务管理可溯源、患者及家属知情的良性氛围,进一步提升了医院管理能力和社会效益。

关键词：医疗器械唯一标识医用耗材监管妇幼专科医院

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首批HEK293细胞DNA含量测定国家标准品的制备

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中国生物制品学杂志 2024年第3期37卷 316-321页

作者：王光裕杨靖清魏长龙周泽鑫杨志行黄钰周勇中国食品药品检定研究院药品监管科学全国重点实验室北京100050 广州派真生物技术有限公司广东广州510670 湖州申科生物技术有限公司浙江湖州313000 武昌首义学院湖北武汉430064

目的制备HEK293细胞DNA含量测定用国家标准品,以期为行业内HEK293细胞残余DNA的测定提供支持。方法使用Genomic-tip 500/G以及基因组DNA纯化试剂制备HEK293细胞DNA,以其为标准物质原料,采用紫外分光光度法和琼脂糖凝胶电泳法进行纯度和... 详细信息

目的制备HEK293细胞DNA含量测定用国家标准品,以期为行业内HEK293细胞残余DNA的测定提供支持。方法使用Genomic-tip 500/G以及基因组DNA纯化试剂制备HEK293细胞DNA,以其为标准物质原料,采用紫外分光光度法和琼脂糖凝胶电泳法进行纯度和含量筛选,随后稀释至浓度约为100 ng/μL后,按160μL/支进行分装。组织5家不同实验室,采用紫外分光光度法进行协作标定,并评价其稳定性和适用性。结果制备的HEK293细胞DNA国家标准品经检测,A260/A280均在1.8~2.0之间,电泳图谱为单一条带,符合规定。该标准品经5家实验室协作标定,共得到78个有效数据,平均含量为104.8 ng/μL,相对标准偏差(relative standard deviation,RSD)为4.2%,均数的95%可信区间为103.8~105.8 ng/μL,单次测定的95%参考值范围为96.0~113.6 ng/μL,平均可信限率为1.0%,推荐保存条件为-80℃。采用2个不同型号的荧光定量PCR仪进行适用性研究,该标准品在0.3~3000 pg/反应范围内适用性良好,扩增效率分别为101%和95%,标准曲线R^(2)分别为0.9992和0.9995。结论该批HEK293细胞DNA国家标准品各项指标均符合要求,可作为国家标准品用于荧光定量PCR检测,含量定为104.8 ng/μL,批号为270039-202301。

关键词： HEK293细胞宿主残余DNA 国家标准品荧光定量PCR

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A pseudoclassical theory for the wavepacket dynamics of the kicked rotor model

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 34-43页

作者： zhixing Zou Jiao Wang Department of Physics and Key Laboratory of Low Dimensional Condensed Matter Physics(Department of Education of Fujian Province) Xiamen UniversityXiamen 361005China Lanzhou Center for Theoretical Physics Lanzhou UniversityLanzhou 730000China

In this study, we propose a generalized pseudoclassical theory for the kicked rotor model in an attempt to discern the footprints of the classical dynamics in the deep quantum regime. Compared with the previous pseudoclassical theory that applies only in the neighborhoods of the lowest two quantum resonances, the proposed theory is applicable in the neighborhoods of all quantum resonances in principle by considering the quantum effect of the free rotation at a quantum resonance. In particular, it is confirmed by simulations that the quantum wavepacket dynamics can be successfully forecasted based on the generalized pseudoclassical dynamics, offering an intriguing example where it is feasible to bridge the dynamics in the deep quantum regime to the classical dynamics. The application of the generalized pseudoclassical theory to the PT-symmetric kicked rotor is also discussed.

关键词： quantum-classical correspondence kicked rotor model pseudoclassical theory wavepacket dynamics

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Neuromorphic circuits based on memristors: endowing robots with a human-like brain

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Journal of Semiconductors 2024年第6期45卷 47-63页

作者： Xuemei Wang Fan yang Qing Liu Zien Zhang zhixing Wen Jiangang Chen Qirui Zhang Cheng Wang Ge Wang Fucai Liu School of Optoelectronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313099China

Robots are widely used,providing significant convenience in daily life and production.With the rapid development of artificial intelligence and neuromorphic computing in recent years,the realization of more intelligent robots through a pro-found intersection of neuroscience and robotics has received much attention.Neuromorphic circuits based on memristors used to construct hardware neural networks have proved to be a promising solution of shattering traditional control limita-tions in the field of robot control,showcasing characteristics that enhance robot intelligence,speed,and energy efficiency.Start-ing with introducing the working mechanism of memristors and peripheral circuit design,this review gives a comprehensive analysis on the biomimetic information processing and biomimetic driving operations achieved through the utilization of neuro-morphic circuits in brain-like control.Four hardware neural network approaches,including digital-analog hybrid circuit design,novel device structure design,multi-regulation mechanism,and crossbar array,are summarized,which can well simulate the motor decision-making mechanism,multi-information integration and parallel control of brain at the hardware level.It will be definitely conductive to promote the application of memristor-based neuromorphic circuits in areas such as intelligent robotics,artificial intelligence,and neural computing.Finally,a conclusion and future prospects are discussed.

关键词： neuromorphic devices neuromorphic circuits hardware networks memristors humanlike robots

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Analysis on the turning point of dynamic in-plane compressive strength for a plain weave composite

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Defence Technology（防务技术） 2024年第2期32卷 485-495页

作者： Xiaoyu Wang zhixing Li Licheng Guo Zhenxin Wang Jiuzhou Zhao Department of Astronautic Science and Mechanics Harbin Institute of TechnologyHarbin150001China AECC Commercial Aircraft Engine Co LTDShanghai201108China

Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate of composites was established. Then the upper limit of strain rate, restricted by stress equilibrium and constant loading rate, was rationally estimated and confirmed by tests. Within the achievable range of 0.001/s-895/s, it was found that the strength increased first and subsequently decreased as the strain rate increased. This feature was also reflected by the turning point(579/s) of the bilinear model for strength prediction. The transition in failure mechanism, from local opening damage to completely splitting destruction, was mainly responsible for such strain rate effects. And three major failure modes were summarized under microscopic observations: fiber fracture, inter-fiber fracture, and interface delamination. Finally, by introducing a nonlinear damage variable, a simplified ZWT model was developed to characterize the dynamic mechanical response. Excellent agreement was shown between the experimental and simulated results.

关键词： Plain weave composite Dynamic strength Quantitative criterion Turning point Failure mechanism

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Switched-capacitor Based Seven-level Boost Inverter with a Reduced Number of Devices

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 381-391页

作者： Weijie Lin Jun Zeng Bo Fu zhixing Yan Junfeng Liu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China WISDRI Engineering&Research Incorporation Limited Wuhan 430074China Department of Energy Aalborg UniversityAalborg 9220Denmark School of Automation Science and Engineering South China University of TechnologyGuangzhou 510641China

The conventional multilevel inverters(MLIs)have the disadvantages of numerous devices,incapacity of boost,unbalance for capacitor’s voltage,high complexity for control,and etc.Motivated by this issue,a seven-level boost inverter(7LBI)based on a switched capacitor is presented for singlephase applications in this paper.The proposed 7LBI using only seven transistors can achieve seven output levels,1.5 voltage gain,and natural balance of capacitors’voltages without sensors or other auxiliary methods,which illustrates its suitability for the applications of renewable energy generation.The configuration of topology and operating principles are illustrated in detail.The natural balance of capacitors and capacitance calculations are deduced as well.Moreover,the comparative study is conducted for different types of MLIs.The results illustrate the merits of the proposed 7LBI with respect to reduced devices,lower voltage stress,and less power loss.Finally,a simulation for the proposed 7LBI with PWM modulation is realized based on the theoretical analysis;an experimental prototype is also implemented,verifying multilevel output,boost ability,natural balance for switched capacitors,and performance of transient response.

关键词： Multilevel inverters voltage gain natural balance renewable energy generation reduced number of elements

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STUDY ON COMPOSITION DESIGN OF A SUPERALLOY

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Acta Metallurgica Sinica(English Letters) 1994年第3期7卷 187-193页

作者： WANG zhixing, XIE Shishu, yang Hongcai, LIU ShiguiNortheastern University, Shenyang, China Northeastern Univ Shenyang China

A new superalloy without Co, Ta and Hf has been developed. The high temperature creep properties of the alloy approach to that of Mar-M246 superallov and with good antioxidation and anticorrosion abilities.

关键词： alloy design superalloy Mar-M246 alloy

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