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应用于全电控智能井的无线电能传输系统设计

石油机械 2025年第1期53卷 28-36页

作者：宋久旭周礼城汪跃龙李世豪西安石油大学陕西省油气井测控技术重点实验室

无线电能传输系统是全电控智能井的重要组成部分,为井下测控设备提供可靠和高质量电能,然而其设计方法的缺失已成为限制国内全电控智能井研发的关键技术之一。为此,对井下无线电能传输系统的设计进行了深入研究,在分析谐振式无线电能传... 详细信息

无线电能传输系统是全电控智能井的重要组成部分,为井下测控设备提供可靠和高质量电能,然而其设计方法的缺失已成为限制国内全电控智能井研发的关键技术之一。为此,对井下无线电能传输系统的设计进行了深入研究,在分析谐振式无线电能传输技术的基础上,根据脱接头实际结构完成了松耦合变压器设计。Maxwell软件对匝数比为n∶m松耦合变压器(8≤n,m≤12)仿真结果表明,匝数比12∶12的松耦合变压器的发射线圈和接收线圈,不仅具有0.844的耦合系数,而且2个线圈电感量之差仅为2.83%,是研制无线充电系统的理想选择。仿真分析了发射线圈和接收线圈径向上的距离和轴向上的偏移对耦合系数的影响。使用场路耦合仿真的方法对无线电能传输系统进行了仿真,分析了无线电能传输系统的输出电压和谐振电流等关键波形,结果显示,无线电能传输系统的效率达到了48.29%,可以满足井下电能传输需求。研究结果可为石油井下设备无线电能传输系统的设计提供一定的参考。

关键词：全电控智能井无线电能传输系统松耦合变压器耦合仿真

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玉米须黄酮化学成分与药理作用研究进展

药学实践与服务 2025年第2期43卷 51-58页

作者：周丽城欧已铭王园上海中侨职业技术大学食品药品学院上海201514

玉米须是玉米的干燥花柱和柱头,我国常用传统中药,具有平肝利胆、利尿消肿之功效。玉米须还被广泛用作茶和功能食品。玉米须富含黄酮类化合物,为玉米须中主要的生物活性成分。近年来,玉米须黄酮的化学、分析、药理、药代动力学及安全性... 详细信息

玉米须是玉米的干燥花柱和柱头,我国常用传统中药,具有平肝利胆、利尿消肿之功效。玉米须还被广泛用作茶和功能食品。玉米须富含黄酮类化合物,为玉米须中主要的生物活性成分。近年来,玉米须黄酮的化学、分析、药理、药代动力学及安全性评价方面的研究取得了较多的进展。黄酮化学成分的研究丰富了玉米须中黄酮类化合物的种类,多项药理学研究证实和拓展了玉米须黄酮的功效,安全性评价为玉米须黄酮的安全应用提供了理论依据。通过文献查阅,综述近10年来玉米须黄酮的提取工艺、成分表征、含量测定、药理作用及安全性等方面的研究进展,为玉米须黄酮的进一步开发及应用提供依据。

关键词：玉米须黄酮化学成分药理作用安全性

Strategies for efficient extracellular secretion of recombinant cyclomaltodextrinase by Escherichia coli

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Food Bioscience 2022年第6期50卷 1980-1987页

作者： Luhua Zheng Bo Jiang Jingjing Chen licheng zhou Tao Zhang State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxiJiangsu214122China International Joint Laboratory on Food Safety Jiangnan UniversityWuxiJiangsu214122China

Cyclomaltodextrinase (CDase, EC 3.***.1.54) is used in the preparation of maltooligosaccharides with a specific degree of polymerization by hydrolyzing cyclodextrins. Extracellular secretion of CDase is beneficial in promoting its application potential. However, a major barrier is that proteins are difficult to cross the inner and outer membranes of cells. Herein, we made an effort to increase the permeability of cell membrane by the deletion of lipopolysaccharide synthesis-related gene (lpxM ). In addition, glycine and Ca^(2+) assisted in the extracellular secretion of recombinant CDase from Bacillus sphaericus E−244. The extracellular fermentation activity of CDase was 2.88 U/mL when ΔycjM -ΔmalS -ΔlpxM was cultured with 1 mM glycine and 5 mM Ca^(2+) for 20 h, accounting for 78.67% of the total fermentation activity, which was 6.26-fold and 6.45-fold higher than that of the parent strain, respectively. Glycine increased cell lysis and disrupted cell morphology, and Ca^(2+) repaired glycine-induced cell growth inhibition. Significantly, deletion of lpxM replaced the use of glycine to a considerable extent, and half the CDase extracellular secretion time.

关键词： Extracellular secretion Cyclomaltodextrinase Gene deletion Lipopolysaccharide

Experimental Study of Hygrothermal and Ultraviolet Aging on the Flexural Performance of Epoxy Polymer Mortar

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Acta Mechanica Solida Sinica 2021年第4期34卷 539-549页

作者： Xinhua Li Dongpeng Ma Zhaoming Lu Yiping Liu Zhenyu Jiang Liqun Tang Zejia Liu licheng zhou School of Civil Engineering and Transportation State Key Laboratory of Subtropical Building ScienceSouth China University of TechnologyGuangzhou510640China

This paper studies the effects of hygrothermal environment at different temperatures and ultraviolet(UV)radiation on the bending properties of epoxy polymer mortar(EPM).The microstructure changes of EPM during aging were studied by scanning electron microscopy,and the bending properties of EPM were predicted by the Arrhenius *** results showed that the bending properties of EPM were greatly affected by the temperature in the hygrothermal aging,but not evidently affected by ultraviolet radiation in UV *** prediction of Arrhenius model shows that the EPM will steadily retain 92.8%,89.1%and 79.4%of the original flexural strength after long-term hygrothermal aging at 40∘C,60∘C and 80∘C,respectively.

关键词： Epoxy polymer mortar Ultraviolet radiation Hygrothermal environment Accelerated aging Flexural strength Arrhenius law

Enhanced flexural performance of epoxy polymer concrete with short natural fibers

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Science China(Technological Sciences) 2018年第8期61卷 1107-1113页

作者： HU Bin ZHANG NanLi LIAO YuTian PAN ZhiWei LIU YiPing zhou licheng LIU ZeJia JIANG ZhenYu School of Civil Engineering and Transportation State Key Laboratory of Subtropical Building Science South China University of Technology The State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences

Epoxy polymer concrete(EPC) has found various applications in civil engineering. To enhance the flexural performance of EPC,two kinds of short natural fibers with high specific strength(sisal fibers and ramie fibers) have been incorporated into EPC. The results of mechanical tests show that a small loading of natural fibers(0.36 vol%) can significantly increase the flexural strength of EPC by 25.3%(ramie fibers) or 10.4%(sisal fibers). This enhancement is achieved without any sacrifice of compressive strength of EPC. The reinforcing effects of short natural fibers on the flexural properties and compressive properties of EPC decrease with further increase in fiber content, due to the insufficient wetting of fibers by epoxy resin which results in poor interfacial bonding. The reinforcing mechanisms of short natural fibers are explored according to the observation of fracture surfaces and micromechanical modelling. It is found that the parallel model based on the rule of mixture can be a good approximation to describe the improvement in flexural strength of the short natural fiber reinforced EPC at low fiber volume fractions.

关键词： epoxy polymer concrete (EPC) natural fibers fiexural strength micromechanics models

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印尼偏远地区移动通信基站供电解决方案

农村电气化 2025年第1期 12-14页

作者：胡春波余亮周里程祝昱吴勇烽火通信科技股份有限公司湖北武汉430205

针对偏远岛屿及山区地区基站由于电网覆盖差,供电可靠性低,不能使用市电供电或者市电供电不稳定问题。文章对不同功耗设备配置的基站供电系统进行研究,开发了一套基于基站光伏发电供电系统的供电方案。成功解决了基站供电问题,提高了基... 详细信息

针对偏远岛屿及山区地区基站由于电网覆盖差,供电可靠性低,不能使用市电供电或者市电供电不稳定问题。文章对不同功耗设备配置的基站供电系统进行研究,开发了一套基于基站光伏发电供电系统的供电方案。成功解决了基站供电问题,提高了基站供电可靠性。

关键词：基站供电系统光伏发电系统供电可靠性

Heterogeneous parallel computing accelerated iterative subpixel digital image correlation

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Science China(Technological Sciences) 2018年第1期61卷 74-85页

作者： HUANG JianWen ZHANG LingQi JIANG ZhenYu DONG ShouBin CHEN Wei LIU YiPing LIU ZeJia zhou licheng TANG LiQun State Key Laboratory of Subtropical Building Science School of Civil Engineering and Transportation South China University of Technology School of Computer Science South China University of Technology The State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences

Parallel computing techniques have been introduced into digital image correlation(DIC) in recent years and leads to a surge in computation speed. The graphics processing unit(GPU)-based parallel computing demonstrated a surprising effect on accelerating the iterative subpixel DIC, compared with CPU-based parallel computing. In this paper, the performances of the two kinds of parallel computing techniques are compared for the previously proposed path-independent DIC method, in which the initial guess for the inverse compositional Gauss-Newton(IC-GN) algorithm at each point of interest(POI) is estimated through the fast Fourier transform-based cross-correlation(FFT-CC) algorithm. Based on the performance evaluation, a heterogeneous parallel computing(HPC) model is proposed with hybrid mode of parallelisms in order to combine the computing power of GPU and multicore CPU. A scheme of trial computation test is developed to optimize the configuration of the HPC model on a specific computer. The proposed HPC model shows excellent performance on a middle-end desktop computer for real-time subpixel DIC with high resolution of more than 10000 POIs per frame.

关键词： digital image correlation(DIC) inverse compositional Gauss-Newton(IC-GN) algorithm heterogeneous parallel computing graphics processing unit(GPU) multicore CPU real-time DIC

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用于软材料的中应变率LSHPB系统及应用

爆炸与冲击 2025年第03期45卷 3-12页

作者：徐沛栋倪萍杨宝蒋震宇刘逸平刘泽佳周立成汤立群华南理工大学土木与交通学院亚热带建筑科学国家重点实验室

生物软材料大多是高含水率的超软材料，其力学性能在宽应变率范围内随着应变率的提高而非线性增强。然而由于实验条件的限制，在中应变率下对超软材料进行大变形测试显得比较困难。设计并建造了长15 m的双子弹电磁驱动长分离式霍普金森... 详细信息

生物软材料大多是高含水率的超软材料，其力学性能在宽应变率范围内随着应变率的提高而非线性增强。然而由于实验条件的限制，在中应变率下对超软材料进行大变形测试显得比较困难。设计并建造了长15 m的双子弹电磁驱动长分离式霍普金森压杆（long split Hopkinson pressure bar, LSHPB）系统，可用于超软材料的大变形中应变率测试。使用该LSHPB系统和高速SHPB系统分别对硅橡胶进行了测试，比较两者的实验结果，验证了系统的可靠性。应用LSHPB系统测量了聚乙烯醇（polyvinyl alcohols, PVA）水凝胶在中应变率下的力学性能，并且结合已有的低和高应变率的数据分析，说明了中应变率动态性能测试的必要性。

关键词：中应变率测试 LSHPB系统 PVA水凝胶动态力学行为

MoS2 Nanosheets Sensitized with Quantum Dots for Room-Temperature Gas Sensors

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Nano-Micro Letters 2020年第5期12卷 20-32页

作者： Jingyao Liu Zhixiang Hu Yuzhu Zhang HuaYao Li Naibo Gao Zhilai Tian licheng zhou Baohui Zhang Jiang Tang Jianbing Zhang Fei Yi Huan Liu School of Optical and Electronic Information Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology1037 Luoyu RoadWuhan 430074People’s Republic of China

The Internet of things for environment monitoring requires high performance with low power-consumption gas sensors which could be easily integrated into large-scale sensor *** semiconductor gas sensors have many advantages such as excellent sensitivity and low cost,their application is limited by their high operating ***-dimensional(2D)layered materials,typically molybdenum disulfide(MoS2)nanosheets,are emerging as promising gas-sensing materials candidates owing to their abundant edge sites and high in-plane carrier *** work aims to overcome the sluggish and weak response as well as incomplete recovery of MoS2 gas sensors at room temperature by sensitizing MoS2 nanosheets with PbS quantum dots(QDs).The huge amount of surface dangling bonds of QDs enables them to be ideal receptors for gas *** sensitized MoS2 gas sensor exhibited fast and recoverable response when operated at room temperature,and the limit of NO2 detection was estimated to be 94 *** strategy of sensitizing 2D nanosheets with sensitive QD receptors may enhance receptor and transducer functions as well as the utility factor that determine the sensor performance,offering a powerful new degree of freedom to the surface and interface engineering of semiconductor gas sensors.

关键词： Gas sensor Room temperature Molybdenum disulfide Quantum dot Nitrogen dioxide