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汽油中铅、铁、锰含量测定方法研究

广东化工 2022年第20期49卷 33-37页

作者：王荣华林志生张泽鹏张文媚高欢广东省惠州市石油产品质量监督检验中心广东惠州516003

针对汽油中铅、铁、锰含量不同的测定方法进行研究,本项目使用原子吸收分光光度法、能量色散X射线荧光光谱法、电感耦合等离子体发射光谱法三种不同检测方法测试汽油中的铅、铁、锰含量,并从测量准确性、使用成本、工作效率、人员要求... 详细信息

针对汽油中铅、铁、锰含量不同的测定方法进行研究,本项目使用原子吸收分光光度法、能量色散X射线荧光光谱法、电感耦合等离子体发射光谱法三种不同检测方法测试汽油中的铅、铁、锰含量,并从测量准确性、使用成本、工作效率、人员要求、环境友好等方面进行比较。三种检测方法的测定结果均与实验室间比对结果相近,结果满意。原子吸收分光光度法和能量色散X射线荧光光谱法国家目前有现行的检测标准,在实际检测中,能量色散X射线荧光光谱法因其操作简便、检测时间短、前处理少、对环境友好等方面优势是目前较为推荐的检测手段。同时,本项目也为用电感耦合等离子体发射光谱法检测汽油中的铅、铁、锰含量提供了可行性的研究方向。

关键词：铅铁锰汽油能量射散X射线荧光光谱法原子吸收分光光度法电感耦合等离子体发射光谱法

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诱饵式远程水下视频技术的研究进展

中国水产科学 2021年第10期28卷 1359-1372页

作者：欧哲扬吴忠鑫张泽鹏 TWEEDLEY James 董世淇王兆国高东奎刘敏邢彬彬田涛大连海洋大学辽宁省海洋牧场工程技术研究中心大连海洋大学设施渔业教育部重点实验室默多克大学哈里巴特勒研究所可持续水生生态系统中心默多克大学

诱饵式远程水下视频技术(baitedremoteunderwatervideo,BRUV)是一种用于记录鱼类相对丰度和物种行为的监测技术,具有无破坏性、成本低且易于复制、适用范围广等优点,已广泛应用于全球多种栖息地的资源调查与评估,但目前其研究应用在国... 详细信息

诱饵式远程水下视频技术(baitedremoteunderwatervideo,BRUV)是一种用于记录鱼类相对丰度和物种行为的监测技术,具有无破坏性、成本低且易于复制、适用范围广等优点,已广泛应用于全球多种栖息地的资源调查与评估,但目前其研究应用在国内尚属空白。本文系统分析总结了BRUV的研究进展,并对BRUV的发展进行了展望。分析结果建议BRUV采用前向视角结构可得到更大的视野;轻巧且易于使用的GoPro相机更适合于光线充足的浅海海域(<40m)调查;调查时饵料建议采用类似沙丁鱼的油性鱼类,有利于对肉食性鱼类的诱集;BRUV使用前,可通过观测物种数和丰度的累计曲线来确定其合理部署时间,通常底层BRUV60min的部署时间已足够。BRUV记录期间,所见到的某一个物种的个体最大数量(MaxN)是BRUV表征物种相对丰度时广泛使用的度量指标。本文可为国内利用BRUV技术开展鱼类资源调查与评估工作提供参考,为BRUV在我国无破坏性海洋生物调查技术的发展以及在海洋牧场鱼类资源监测中的应用提供支持。

关键词：诱饵式远程水下视频技术(BRUV) 海洋牧场鱼类资源监测无破坏性监测技术

Effect of vortex dynamics and instability characteristics on the induced drag of trailing vortices

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Chinese Journal of Aeronautics 2022年第9期35卷 160-173页

作者： zepeng CHENG Shiyan zhang Yang XIANG Chun SHAO Miao zhang Hong LIU Yingchun CHEN School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of China Ltd.Shanghai 201210China

In this paper, trailing vortices generated by three wingtip configurations, namely the M6wing and the M6 wing with a blended or split winglet, are experimentally investigated using the Stereo Particle Image Velocimetry(SPIV) technology. Then, linear stability analysis is performed to investigate instability characteristics. Three corresponding trailing vortex patterns, including the isolated trailing vortex without wake(pattern v) and with wake(pattern v-w), co-rotating vortex pair(pattern v-v), are observed in experiments. The strength of trailing vortices, characterized by circulation, is reduced after installing winglets as expected, and the strength of pattern v-v can be further suppressed compared with pattern v-w. Moreover, instability characteristics, such as the eigenvalue spectrum and perturbation mode, are distinctive among these three vortex *** distribution of eigenvalue spectrums indicates that pattern v and pattern v-w are temporally“marginally stable”, while pattern v-v is temporally “unstable.” The primary perturbation mode of pattern v and pattern v-w is the m =-1 helical mode, while |m|>1 for the case of pattern *** effect of vortex dynamics and instability characteristics can be concluded in two ***, the value of induced drag is polluted by about 3% from vortex wandering since vortex wandering affects the tangential velocity and streamwise vorticity of trailing vortices. Secondly, the growth rate and penetration depth perturbation mode affect trailing vortex evolution and further affect induced drag. Specifically, the larger the growth rate and penetration depth are, the more turbulence injects inside the vortex core, thus leading to a quicker and more intense attenuation of trailing vortex, as well as a smaller induced drag. This finding can guide us to manipulate the induced drag in flow control.

关键词： Induced drag Linear stability analysis SPIV Trailing vortex Vortex flow Winglet

UWB技术的RLS EKF室内定位算法研究

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单片机与嵌入式系统应用 2023年第2期23卷 70-72页

作者：张泽鹏李桂林周海俊李雯大连交通大学计算机与通信工程学院大连116028

针对当前UWB技术在传统厂区布站方式下室内定位误差较大,无法良好实现对象的三维显示问题,基于多传感器融合,本文提出一种将UWB数据与IMU数据进行先预处理、后融合的算法。该方法通过TOF测距后将UWB数据进行小波阈值去噪,递推最小二乘定... 详细信息

针对当前UWB技术在传统厂区布站方式下室内定位误差较大,无法良好实现对象的三维显示问题,基于多传感器融合,本文提出一种将UWB数据与IMU数据进行先预处理、后融合的算法。该方法通过TOF测距后将UWB数据进行小波阈值去噪,递推最小二乘定位,并与IMU数据进行扩展卡尔曼滤波融合,从而减小标签的三维距离误差,提高定位精度,实现对厂区可移动设备的实时监控管理。仿真结果表明,基于多传感器融合的RLS EKF室内定位能够减小标签三维定位误差,提高定位的准确性,满足厂区室内实时定位的精度要求。

关键词： UWB IMU 小波阈值去噪递推最小二乘扩展卡尔曼滤波

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4MZ-4自走箱式采棉机风送歧管流体分析及结构优化

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新疆农机化 2024年第2期 35-37,47页

作者：张泽朋林兆焯巩鹏王萧黄开鹏铁建重工新疆有限公司新疆乌鲁木齐830009

针对最新研制的4MZ-4自走箱式采棉机,为分析其风送系统流动特性,并使风量在四个输送管路中分配均匀,利用Hypermesh、Fluent软件对四行机离心风机及一分四歧管进行了流体域建模及数值分析,分析得到离心风机出口流量数据,以风机出口流量... 详细信息

针对最新研制的4MZ-4自走箱式采棉机,为分析其风送系统流动特性,并使风量在四个输送管路中分配均匀,利用Hypermesh、Fluent软件对四行机离心风机及一分四歧管进行了流体域建模及数值分析,分析得到离心风机出口流量数据,以风机出口流量作为歧管入口边界条件计算歧管各出口流量及流量配比,并根据歧管内空气流动状态对歧管结构进行优化,优化后歧管的风量配比均匀性得到显著改善。

关键词：采棉机风送歧管流体分析结构优化

Using thermodynamic parameters to study self-healing and interface properties of crumb rubber modified asphalt based on molecular dynamics simulation

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 109-122页

作者： Dongliang HU Jianzhong PEI Rui LI Jiupeng zhang Yanshun JIA zepeng FAN School of Transportation Southeast UniversityNanjing 211189China School of Highway Chang’an UniversityXi’an 710064China School of Transportation Science and Engineering Harbin Institute of TechnologyHarbin 150090China

The thermodynamic property of asphalt binder is changed by the addition of crumb rubber,which in turn influences the self-healing property as well as the cohesion and adhesion within the asphalt-aggregate *** study investigated the self-healing and interface properties of crumb rubber modified asphalt(CRMA)using thermodynamic parameters based on the molecular simulation *** molecular models of CRMA were built with representative structures of the virgin asphalt and the crumb *** aggregate was represented by SiO2 and Al2O3 *** selfhealing capability was evaluated with the thermodynamic parameter wetting time,work of cohesion and *** interface properties were evaluated by characterizing the adhesion capability,the debonding potential and the moisture susceptibility of the asphalt-aggregate *** self-healing capability of CRMA is found to decrease as the rubber content *** asphalt-Al2O3 interface with higher rubber content has stronger adhesion and moisture *** the influence of crumb rubber on the interfacial properties of asphalt-SiO2 interface has no statistical *** with the interfacial properties of the asphalt-SiO2 interface,the asphalt-Al2O3 interface is found to have a stronger adhesion but a worse moisture susceptibility for its enormous thermodynamic potential for water to displace the asphalt binder.

关键词： crumb rubber modified asphalt surface free energy self-healing interface properties molecular dynamics simulation

Lipid levels and insulin resistance markers in patients with colorectal cancer:Propensity score matching analysis

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 130-142页

作者： Ren-Hao Hu Dong-Yi Yan Ke-Hui zhang Di zhang Xi-Mao Cui Xiao-Hua Jiang Shun zhang Department of Gastrointestinal Surgery Shanghai East HospitalSchool of MedicineTongji UniversityShanghai 200120China School of Medicine Tongji UniversityShanghai 200092China Department of Emergency Medicine Shanghai East HospitalSchool of MedicineTongji UniversityShanghai 200120China

BACKGROUND Colorectal cancer(CRC)is a prevalent malignant neoplasm characterized by subtle early *** To investigate the correlation among serum lipid profiles,the triglyceride-glucose(TyG)index,and the atherosclerotic index(AI)in patients with ***,it explored the clinical diagnostic utility of combining serum lipids with cancer antigens in the context of *** A retrospective analysis encompassed 277 patients with CRC and 1034 healthy *** Following propensity score matching,patients with CRC exhibited significantly reduced levels of serum triglyceride(TG),total cholesterol(TC),high-density lipoprotein cholesterol,and low-density lipoprotein cholesterol(LDL-C),as well as a diminished TyG ***,they displayed elevated AI levels compared to their healthy *** in advanced stages exhibited lower serum levels of TG,TC,and LDL-C compared to those in early *** with positive lymph node metastasis demonstrated reduced levels of TG,LDL-C,and the TyG *** operating characteristic analysis revealed that the combination of the TyG index,carcinoembryonic antigen,and carbohydrate antigen 19-9 yielded the highest positive prediction rate for CRC at 75.3%.CONCLUSION Preoperative serum lipid profiles exhibit a robust association with patients with *** concurrent assessment of multiple serum lipids and cancer antigens effectively enhances the diagnostic accuracy for CRC.

关键词： Colorectal cancer Serum lipids Triglyceride-glucose index Atherosclerotic index Diagnostic marker

Instability characteristics of a co-rotating wingtip vortex pair based on bi-global linear stability analysis

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Chinese Journal of Aeronautics 2021年第5期34卷 1-16页

作者： zepeng CHENG Siyi QIU Yang XIANG Chun SHAO Miao zhang Hong LIU School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of China Ltd.Shanghai 201210China

The Stereo Particle Image Velocimetry(SPIV)technology is applied to measure the wingtip vortices generated by the up-down symmetrical split ***,the temporal biglobal Linear Stability Analysis(bi-global LSA)is performed on this nearly equal-strength corotating vortex pair,which is composed of an upper vortex(vortex-u)and a down vortex(vortex-d).The results show that the instability eigenvalue spectrum illustrated by(ωr,ω_(i))contains two types of branches:discrete branch and continuous *** discrete branch contains the primary branches of vortex-u and vortex-d,the secondary branch of vortex-d and coupled branch,of which all of the eigenvalues are located in the unstable half-plane ofω_(i)>0,indicating that the wingtip vortex pair is temporally *** contrast,the eigenvalues of the continuous branch are concentrated on the half-plane ofω_(i)<0 and the perturbation modes correspond to the freestream *** the primary branches of vortex-u and vortex-d,Mode P_(u) and Mode Pd are the primary perturbation modes,which exhibit the structures enclosed with azimuthal wavenumber m and radial wavenumber n,***,the results of stability curves for vortex-u and vortex-d demonstrate that the instability growth rates of vortex-u are larger than those of vortex-d,and the perturbation energy of Mode P_(u) is also larger than that of Mode ***,the perturbation energy of Mode P_(u) is up to 0.02650 and accounts for 33.56%percent in the corresponding branch,thereby indicating that the instability development of wingtip vortex is dominated by Mode P_(u).By further investigating the topological structures of Mode P_(u) and Mode Pd with streamwise wavenumbers,the most unstable perturbation mode with a large azimuthal wavenumber of m=5-6 is identified,which imposes on the entire core region of *** large azimuthal wavenumber perturbation mode can suggest the potential physical-based flow control strategy by manipulating it.

关键词： Bi-global linear stability analysis Perturbation mode SPIV Vortex flow Winglet Wingtip vortex

High Order Finite Difference WENO Methods for Shallow Water Equations on Curvilinear Meshes

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Communications on Applied Mathematics and Computation 2023年第1期5卷 485-528页

作者： zepeng Liu Yan Jiang Mengping zhang Qingyuan Liu School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026AnhuiChina School of Mathematics and Physics Anhui Jianzhu UniversityHefei 230026AnhuiChina

A high order finite difference numerical scheme is developed for the shallow water equations on curvilinear meshes based on an alternative flux formulation of the weighted essentially non-oscillatory(WENO)*** exact C-property is investigated,and comparison with the standard finite difference WENO scheme is *** derivation and numerical results show that the proposed finite difference WENO scheme can maintain the exact C-property on both stationarily and dynamically generalized coordinate *** Harten-Lax-van Leer type flux is developed on general curvilinear meshes in two dimensions and verified on a number of benchmark problems,indicating smaller errors compared with the Lax-Friedrichs *** addition,we propose a positivity-preserving limiter on stationary meshes such that the scheme can preserve the non-negativity of the water height without loss of mass conservation.

关键词： Shallow water equation Well-balanced High order accuracy WENO scheme Curvilinear meshes Positivity-preserving limiter