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PIV analysis and high-speed photographic observation of cavitating flow field behind circular multi-orifice plates

Water Science and Engineering 2020年第2期13卷 145-153页

作者： zhi-ping guo Xi-huan Sun zhi-yong Dong College of Hydro-Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Transportation Engineering Shanxi Conservancy Technical InstituteYuncheng 044004China College of Civil Engineering and Architecture Zhejiang University of TechnologyHangzhou 310014China

Based on a self-developed hydrodynamic cavitation device with different geometric parameters for circular multi-orifice plates,turbulence characteristics of cavitating flow behind multi-orifice plates,including the effects of orifice number and orifice layout on longitudinal velocity,turbulence intensity,and Reynolds stress,were measured with the particle image velocimetry(PIV)*** regimes of the cavitating flow were also observed with high-speed *** experimental results showed the following:(1)high-velocity multiple cavitating jets occurred behind the multi-orifice plates,and the cavitating flow fields were characterized by topological structures;(2)the longitudinal velocity at each cross-section exhibited a sawtooth-like distribution close to the multi-orifice plate,and each sawtooth indicated one jet issuing from one orifice;(3)there were similar magnitudes and forms for the longitudinal and vertical turbulence intensities at the same cross-section;(4)the variation in amplitude of Reynolds stress increased with an increase in orifice number;and(5)the cavitation clouds in the flow fields became denser with the increase in orifice number,and the clouds generated by the staggered layout of orifices were greater in number than those generated by the checkerboard-type one for the same orifice *** experimental results can be used to analyze the mechanism of killing pathogenic microorganisms through hydrodynamic cavitation.

关键词： Cavitating flow Circular multi-orifice plate PIV technique High-speed photography Turbulence characteristics

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Spectral Characteristics of LiSrBO_3:Tb^(3+) Green Phosphor

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Chemical Research in Chinese Universities 2009年第5期25卷 610-613页

作者： LI Pan-lai WANG zhi-jun YANG zhi-ping guo Qing-lin College of Physics Science ＆ Technology Hebei University Baoding 071002 P. R. China

LiSrBO3：Tb^3＋ green phosphor was synthesized by means of a solid state reaction and its spectral characteristics were studied. The emission spectrum of LiSrBO3：Tb^3＋ consists of four major bands at 486, 544, 595 and 620 nm under the excitation of near ultraviolet irradiation, which are originated from the ^5Da→^7F6, ^5D4→^7F5, ^5D4→^7F4 and ^5D4→^7F3 characteristic transitions of Tb^3＋, respectively. Monitored at 544 nm, the excitation spectrum of the phosphor extends from 220 nm to 390 nm, with the excitation peaks centered at 242, 277, 368 and 381 nm, respectively. The effect of Tb^3＋ concentration on the emission intensity of LiSrBO3：Tb^3＋ was also investigated. The results show that firstly the intensity increases with increasing Tb^3＋ concentration, reaches a maximum value at 3%（molar fraction） Tb^3＋ and then decreases, showing a concentration self-quenching, whose mechanism is proposed as a d-d interaction based on Dexter theory. The emission intensity of LiSrBO3：Tb^3＋ was enhanced by co-doping Li^＋, Na^＋ and K^＋.

关键词： LiSrBO3:Tb^3+ Green phosphor Spectral characteristics

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Photoinduced Electron Transfer in Host-Guest Complexes of Naphthalene Derivatives with p-NBCD and m-NBCD

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Chinese Chemical Letters 2006年第3期17卷 333-336页

作者： Hui Yuan HU Man Zhou ZHU zhi ping ZHANG guo Tao WEN Qing Xiang guo Department of Chemistry University of Science and Technology of China Hefei 230026

A number of naphthalene derivatives containing adamantanamine binding moiety and an （CH2）. （n = 2, 3, 4, 5, 6） spacer were prepared as electron donor. A supramolecular assembly was fabricated by the inclusion complexation of the donor substrates with the host molecules, mono-6-O-p-nitrobenzoyl-β-cyclodextrin （p-NBCD） and mono-6-O-m-nitrobenzoyl-β-cyclodextrin （m-NBCD）, in water. The fluorescence quenching in these systems was studied and detailed Stern-Volmer constants were measured. It revealed that an efficient photoinduced electron transfers （PET） between the naphthalene donors and the cyclodextrin acceptors occurred.

关键词： Cyclodextrin fluorescence quenching photoinduced electron transfer supramolecule.

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Luminescence and Site Occupancy of Eu2＋ in Ba2 Ca（BO3）2

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Chinese Physics Letters 2011年第1期28卷 190-192页

作者： LI Pan-Lai WANG zhi-Jun YANG zhi-ping guo Qing-Lin Colleg-e of Physics Science and Technology Hebei University Baoding 071002

A green phosphor Ba2Ca（BOa）2：Eu2＋ was syntheMzed by a high temperature solid-state reaction method under a reductive amosphere,, The luminescence and site occupancy of Eu2＋ in Ba2Ca（BOa）2 are investigated. Ba2Ca（BO3）2：Eu2＋ shows one green band （537nzn） under 400nln near ultraviolet excitation which is suitable for UV LED. Ca2＋ and Ba2＋ ions in Ba2Ca（BO3）2 are replaced by Eu2＋ ions, the Ba2Ca（BO3）2：Eu2＋ shows a dissymmetrical emission band. The influence of Eu2＋ doping concentrations on the emission intensity of Ba2Ca（BOa）2：Eu2＋ is studied. It is found that the emission intensity is influenced by the Eu2＋ concentration and reaches the maxinmm value at 2% Eu2＋, According to the Dexter theory, the concentration quenching mechanisms of Eu2＋ in Ba2 Ca（B03）2 are the d - d interaction,

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A New Approach to Prepare 2-Acetyl-Mono(5,6,7,8)-Nitro-l,2,3,4-Tetrahydroisoquinolincs

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Chinese Chemical Letters 2000年第10期11卷 857-860页

作者： Chong Zhao RAN, Tat zhi WU, guo ping WANG, Met Hua XIE (Department of Medicinal Chemistry, Shanghai institute of Pharmaceutical industry, Shanghai 200437)

N-Acetyl-P. m or o-nitro-phenylethylamines and (HCHO). were treated in 60% H,SO./HOAc. via α -amidoalkylation to give 2-acetyl-mono(5, 6, 7 or 8)-nitro-l .2,3.4- tetrahydroisoquinolines. Additionally. solme interesting phenomena were observed when the comparison between 2-acetyl-5, 6. 7 or 8-nitro-l,2.3.4-tetrahydroisoqui and 2-alkylsulfonyl-5. 6 or 7nitro-l,2.3,4-tetrahydroisoquinolines was made.

关键词： α-Amidoalkylation 2-acetyl-mono (5 6. 7. 8)-nitro-l.2,3.4-tetrahydroisoqu nitro- I .2.3.4-tetrahydroisoquinolines.

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西部特大城市低碳发展的现状问题及目标策略研究——以西安市为例

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干旱区地理 2017年第2期40卷 434-440页

作者：李治李国平胡振西安建筑科技大学管理学院陕西西安710055 西安交通大学经济与金融学院陕西西安710061

作为应对全球气候变化的关键平台,城市尺度的低碳建设研究具有重要意义。本文以西部特大城市—西安市为例,分别从碳排放量变化趋势、未来发展目标、关键部门能耗系统分析其低碳发展现状,指出存在问题及可能的节能减排潜力,认为西安市高... 详细信息

作为应对全球气候变化的关键平台,城市尺度的低碳建设研究具有重要意义。本文以西部特大城市—西安市为例,分别从碳排放量变化趋势、未来发展目标、关键部门能耗系统分析其低碳发展现状,指出存在问题及可能的节能减排潜力,认为西安市高碳发展模式明显,面临资源禀赋差异、能源消费结构的锁定效应、能源利用效率低、城市空间结构不合理、高能耗建筑多、碳汇能力弱等问题。基于此,制定工业节能技术改造、城市空间合理布局、推广绿色建筑、社会治理创新和政策保障等对策措施。

关键词：低碳发展现状问题目标策略特大城市西安

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管理者任期、内部控制与战略差异

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中国软科学 2016年第12期 132-143页

作者：殷治平张兆国华中科技大学管理学院湖北武汉430074 湖北经济学院会计学院湖北武汉430205

本文运用战略管理理论、委托代理理论和高阶梯队理论,以我国2011—2014年沪深两市A股类上市公司为研究样本,考察了内部控制对战略差异影响以及管理者既有任期和预期任期在这种影响中的调节作用。研究结果表明:内部控制与战略差异呈显著... 详细信息

本文运用战略管理理论、委托代理理论和高阶梯队理论,以我国2011—2014年沪深两市A股类上市公司为研究样本,考察了内部控制对战略差异影响以及管理者既有任期和预期任期在这种影响中的调节作用。研究结果表明:内部控制与战略差异呈显著负相关;管理者既有任期在内部控制影响战略差异中的调节作用呈倒U型;管理者预期任期在内部控制影响战略差异中起正向调节作用。进一步研究表明,在非国有上市公司中内部控制与战略差异的负相关以及管理者既有任期的调节作用均比国有上市公司更显著,而管理者预期任期的调节作用则在国有上市公司中更显著。这些研究结论对企业完善内部控制、合理选择管理者聘期、降低战略风险具有一定的启示意义。

关键词：产权性质管理者任期内部控制战略差异

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NEPE推进剂溶胶的制备与表征

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火炸药学报 2017年第2期40卷 84-87,93页

作者：聂海英杨秋秋黄志萍刘治国韦雪梅湖北航天化学技术研究所湖北襄阳441003

采用乙醚浸泡,氯仿索氏提取制备了硝酸酯增塑聚醚(NEPE)推进剂粗溶胶,然后通过乙醚少量多次洗涤法、色谱法、透析法3种方式进一步提纯制得NEPE推进剂纯溶胶;采用红外光谱、元素分析、核磁共振光谱、凝胶渗透-二极管阵列检测器表征了溶... 详细信息

采用乙醚浸泡,氯仿索氏提取制备了硝酸酯增塑聚醚(NEPE)推进剂粗溶胶,然后通过乙醚少量多次洗涤法、色谱法、透析法3种方式进一步提纯制得NEPE推进剂纯溶胶;采用红外光谱、元素分析、核磁共振光谱、凝胶渗透-二极管阵列检测器表征了溶胶的化学组成。结果表明,NEPE推进剂溶胶由聚乙二醇多异氰酸酯固化反应的聚氨酯片段以及未反应完全的聚乙二醇组成;透析法成本低廉,所得溶胶纯净,杂质含量低于10^(-5)。NEPE推进剂溶胶的分子质量主要集中在10 000~41 800Da,约占总溶胶的80%。老化后推进剂溶胶中大分子聚合物相对较少。

关键词： NEPE推进剂溶胶透析法制备表征

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Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 64-70页

作者： guo-Fu Xu Department of Physics Shandong University

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era, building accurate intermediate-scale nonadiabatic holonomic quantum computers is clearly necessary. Given that measurements are the sole means of extracting information, they play an indispensable role in nonadiabatic holonomic quantum computers. Accordingly, developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great importance. However, while much attention has been given to the research on nonadiabatic holonomic gates, the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely lacking. In this study, we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum computers. The reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic gates. Given these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

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Anomaly Detection of Controllable Electric Vehicles through Node Equation against Aggregation Attack

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Computers, Materials & Continua 2025年第1期82卷 427-442页

作者： Jing guo Ziying Wang Yajuan guo Haitao Jiang State Grid Jiangsu Electric Power Co. Ltd.Research InstituteState Grid Corporation of ChinaNanjing211100China

The rapid proliferation of electric vehicle(EV)charging infrastructure introduces critical cybersecurity vulnerabilities to power grids *** study presents an innovative anomaly detection framework for EV charging stations,addressing the unique challenges posed by third-party aggregation *** approach integrates node equations-based on the parameter identification with a novel deep learning model,xDeepCIN,to detect abnormal data reporting indicative of aggregation *** employ a graph-theoretic approach to model EV charging networks and utilize Markov Chain Monte Carlo techniques for accurate parameter *** xDeepCIN model,incorporating a Compressed Interaction Network,has the ability to capture complex feature interactions in sparse,high-dimensional charging *** results on both proprietary and public datasets demonstrate significant improvements in anomaly detection performance,with F1-scores increasing by up to 32.3%for specific anomaly types compared to traditional methods,such as wide&deep and DeepFM(Factorization-Machine).Our framework exhibits robust scalability,effectively handling networks ranging from 8 to 85 charging ***,we achieve real-time monitoring capabilities,with parameter identification completing within seconds for networks up to 1000 *** research contributes to enhancing the security and reliability of renewable energy systems against evolving cyber threats,offering a comprehensive solution for safeguarding the rapidly expanding EV charging infrastructure.

关键词： Anomaly detection electric vehicle aggregation attack deep cross-network

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