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AN EXPERIMENTAL INVESTIGATION OF PRESSURE AND CAVITATION CHARACTERISTICS OF HIGH VELOCITY FLOW OVER A CYLINDRICAL PROTRUSION IN THE PRESENCE AND ABSENCE OF AERATION

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Journal of Hydrodynamics 2008年第1期20卷 60-66页

作者： DONG zhi-yong LIU zhi-ping wu yi-hong ZHANG Dong China Hydraulic and Municipal Engineering Research Institute Zhejiang University of Technology Hangzhou 310014 China Institute of Water Resources and Hydroelectric Power Research Beijing 100038 China

This article experimentally investigated the pressure and cavitation characteristics of high velocity flow over a surface irregularity with and without aeration in a non-circulating water tunnel system. The surface irregularity is a cylindrical protrusion made of stainless steel of 6 mm diameter and 2 mm height. Pressures with and without aeration were measured with MPX400D pressure transducers and real-timely acquired by a SINOCERA YE6263 data acquisition system. Variations in flow regimes with and without aeration were observed. Pressure profiles and their variations with air concentration upper and lower cylindrical protrusion on the invert and obvert walls were determined. Variations of cavitation number with air concentration lower cylindrical protrusion were analyzed. Also, cavitation numbers in the presence and absence of aeration were compared.

关键词： cylindrical protrusion aeration pressure cavitation number high velocity flow

Numerical simulation and dimension reduction analysis of electromagnetic logging while drilling of horizontal wells in complex structures

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Petroleum Science 2020年第3期17卷 645-657页

作者： Zhen-Guan wu Shao-Gui Deng Xu-Quan He Runren Zhang yi-Ren Fan Xi-Yong Yuan yi-zhi wu Qing Huo Liu School of Geosciences China University of PetroleumQingdao 266580ShandongChina Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071Shandong.China CNPC Key Laboratory for Well Logging China University of PetroleumQingdao 266580ShandongChina Research Institute of Exploration and Development PetroChina Southwest Oil and Gas Field CompanyChengdu 610041SichuanChina Duke University DurhamNC 27705USA

Electromagnetic logging while drilling(LWD)is one of the key technologies of the geosteering and formation evaluation for high-angle and horizontal *** this paper,we solve the dipole source-generated magnetic/electric fields in 2D formations efficiently by the 2.5D finite diff erence ***,by leveraging the field’s rapid attenuation in spectral domain,we propose truncated Gauss–Hermite quadrature,which is several tens of times faster than traditional inverse fast Fourier *** applying the algorithm to the LWD modeling under complex formations,e.g.,folds,fault and sandstone pinch-outs,we analyze the feasibility of the dimension reduction from 2D to *** the formations with smooth lateral changes,like folds,the simplified 1D model’s results agree well with the true responses,which indicate that the 1D simplification with sliding window is ***,for the formation structures with drastic rock properties changes and sharp boundaries,for instance,faults and sandstone pinch-outs,the simplified 1D model will lead to large errors and,therefore,2.5D algorithms should be applied to ensure the accuracy.

关键词： Complex formation structures Horizontal wells Electromagnetic logging while drilling 2.5D algorithm-Model simplification

Effects of different orthokeratology lens designs on slowing axial length elongation in children with myopia

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1843-1849页

作者： Hai-Long Ni Xiang Chen Du-Ya Chen Pei-Ke Hu zhi-yi wu Eye Center the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

AIM:To elucidate whether differences exist in the impact on retarding the elongation of axial length(AL)among children with myopia when utilizing orthokeratology(ortho-k)lenses employing the corneal refractive therapy(CRT)design versus those employing the vision shaping treatment(VST)***:This retrospective clinical trial aimed to collect and analyze AL data from individuals who wore ortho-k lenses for three years.A total of 654 subjects were enrolled and prescribed one of the three specific brands of ortho-k lenses:CRT,Euclid,and *** study’s primary focus was to compare the rates of AL elongation and myopic progression across these three brands of ortho-k ***:In the 3-year follow-up,the AL elongation exhibited variations of 0.73±0.36 mm in the CRT lens group,0.59±0.37 mm in the Euclid lens group,and 0.63±0.38 mm in the Mouldway lens group.A noteworthy disparity emerged between the CRT and Mouldway groups(Pying the VST design exhibited a more favorable impact regarding retarding AL elongation.

关键词： myopia orthokeratology design axial length

Characteristics of high-sulfate wastewater treatment by two-phase anaerobic digestion process with Jet-loop anaerobic fluidized bed

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Journal of Environmental Sciences 2007年第3期19卷 264-270页

作者： WEI Chao-hai, WANG Wen-xiang, DENG zhi-yi, wu Chao-fei School of Environmental Science and Engineering, South China University of Technology, Guangzhou 510640, China. School of Environmental Science and Engineering South China University of Technology Guangzhou 510640 China

A new anaerobic reactor, Jet-loop anaerobic fluidized bed （JLAFB）, was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed （AFB） reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids （VFA） in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/（m^3.d）, the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found.

关键词： Jet-loop anaerobic fluidized bed reactor sulfate wastewater two-phase anaerobic digestion process granule sludge

Delay of ZGA initiation occurred in 2-cell blocked mouse embryos

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Cell Research 2003年第3期13卷 179-185页

作者： JIA JING QIU,wu WEN ZHANG,zhi Li wu,yi HONG WANG,MIN QIAN,yi PING LIInstitute,of Biochemistry and Cell Biology,Shanghai Institutes for Biological Sciences. Chinese Academy of Sciences,200031 Shanghai,ChinaSchool of Life Science,East China Normal University. 200062 Shanghai,China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China School of Life Science East China Normal University Shanghai China

One-cell mouse embryos from KM strain and B6C3F1 strain were cultured in M16 medium,in which2-cell block generally *** of KM strain exhibited 2-cell block,whereas B6C3F1 embryos,which are regarded as a nonblocking strain,proceeded to the 4-cell stage in our culture *** is oftenassumed that the block of early development is due to the failure of zygotic gene activation（ZGA）in *** this study we examined protein synthesis patterns by two-dimensional gel electrophoresis of[35S]methionine radiolabeled 2-cell *** from the blocking strain and the nonblocking strainwere compared in their development both in vitro and in *** detection of TRC expression,a markerof ZGA,at 42 h post hCG in KM embryos developed in vitro suggested that ZGA was also initiated even inthe 2-cell arrested ***,a significant delay of ZGA was observed in KM strain as comparedwith normally developed B6C3F1 *** the very beginning of major ZGA as early as 36 h post

关键词： monse embryo two-cell block zygotic gone activation (ZGA).

Repetitive transcranial magnetic stimulation in Alzheimer’s disease:effects on neural and synaptic rehabilitation

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Neural Regeneration Research 2025年第2期20卷 326-342页

作者： yi Ji Chaoyi Yang Xuerui Pang yibing Yan Yue wu zhi Geng Wenjie Hu Panpan Hu Xingqi wu Kai Wang Department of Neurology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders HefeiAnhui ProvinceChina Collaborative Innovation Center of Neuropsychiatric Disorders and Mental Health HefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina Department of Psychology and Sleep Medicine The Second Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina

Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and *** Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neurodegeneration and ultimately disrupting the operational abilities in daily life,leaving patients *** transcranial magnetic stimulation is a cost-effective,neuro-modulatory technique used for multiple neurological *** the past two decades,it has been widely used to predict cognitive decline;identify pathophysiological markers;promote neuroplasticity;and assess brain excitability,plasticity,and *** has also been applied to patients with dementia,because it can yield facilitatory effects on cognition and promote brain recovery after a neurological ***,its therapeutic effectiveness at the molecular and synaptic levels has not been elucidated because of a limited number of *** study aimed to characterize the neurobiological changes following repetitive transcranial magnetic stimulation treatment,evaluate its effects on synaptic plasticity,and identify the associated *** review essentially focuses on changes in the pathology,amyloidogenesis,and clearance pathways,given that amyloid deposition is a major hypothesis in the pathogenesis of Alzheimer’s *** mechanisms associated with repetitive transcranial magnetic stimulation procedures and different pathways mediating gene transcription,which are closely related to the neural regeneration process,are also ***,we discuss the outcomes of animal studies in which neuroplasticity is modulated and assessed at the structural and functional levels by using repetitive transcranial magnetic stimulation,with the aim to highlight future directions for better clinical translations.

关键词： Alzheimer’s disease amyloid deposition apoptotic mechanisms biomarker neural regeneration neurodegeneration repetitive transcranial magnetic stimulation synaptic plasticity

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川蔓藻属系统分类和演化评述

植物分类学报 2008年第4期46卷 467-478页

作者：赵良成吴志毅北京林业大学生物科学与技术学院北京100083 浙江大学农业与生物技术学院杭州310028

川蔓藻属Ruppia为沉水单子叶植物,世界广布,主要为咸水和盐水生境,具有重要的生态价值、环境指示作用以及植物系统学研究意义。长期以来,川蔓藻属内种的数目以及属的系统位置一直存在争议。根据已有研究资料,目前川蔓藻属共有5个种——... 详细信息

川蔓藻属Ruppia为沉水单子叶植物,世界广布,主要为咸水和盐水生境,具有重要的生态价值、环境指示作用以及植物系统学研究意义。长期以来,川蔓藻属内种的数目以及属的系统位置一直存在争议。根据已有研究资料,目前川蔓藻属共有5个种——***、***、***、***和***得到多数学者的认可。关于其系统位置,主要有隶属于眼子菜科Potamogetonaceae和独立成川蔓藻科Ruppiaceae两种观点。尽管目前许多被子植物分类系统都承认了川蔓藻科,近年来分子系统学研究显示川蔓藻属与丝粉藻科Cymodoceaceae和波喜荡科Posidoniaceae有近的亲缘关系,但对川蔓藻属和眼子菜属Potamogeton区别特征的比较结果倾向于支持将其放在眼子菜科。本文还结合川蔓藻属及相关类群的化石记录和果实特征对其演化进行了初步探讨,化石属Limnocarpus和Midravalva被认为是川蔓藻属较早的祖先类群,并认为该属植物应该是由淡水祖先逐渐演变成现在的咸水生长植物。最后,提出了在川蔓藻属未来研究中有待进一步解决的问题。

关键词：川蔓藻属眼子菜属分类系统位置演化

Numerical Study of Flow and Heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric Heater with Circularly Perforated Baffles

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Journal of Thermal Science 2025年第1期34卷 24-33页

作者： LIN Yongjie ZHANG Cancan wu Yuting ZHANG yi LU Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of Technology

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings（φ）,i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/（Δp）1/3was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29% to 17.18% over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan Shi Qun yi Yao Liu yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Oxygen evolution reaction