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FLOW PAST TWO ROTATING CIRCULAR CYLINDERS IN A SIDE-BY-SIDE ARRANGEMENT

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Journal of Hydrodynamics 2009年第2期21卷 143-151页

作者： GUO Xiao-hui LIN Jian-zhong tu Cheng-xu wang Hao-li China Jiliang University Hangzhou 310018 China

Measurements were performed using Particle Image Velocimetry （PIV） to analyze the modification of flow by the combined effects of the rotation and the Reynolds number on the flow past two rotating circular cylinders in a side-by-side-arrangement at a range of 425 〈 Re ≤ 1130,0 ≤α ≤4 （ α is the rotational speed） at one gap spacing of T / d = 1.11 （T and d are the distance between the centers of two cylinders and the cylinder diameter, respectively）. A new Immersed-Lattice Boltzmann Method （ILBM） scheme was used to study the effect of the gap spacing on the flow. The results show that the vortex shedding is suppressed as rotational speed increases. The flow reaches a steady state when the vortex shedding for both cylinders is completely suppressed at critical rotational speed. As the rotational speed further increases, the separation phenomenon in the boundary layers disappears at the attachment rotational speed. The critical rotational speed and attachment rotational speed become small as Reynolds number increases. The absolute rotational speed of cylinders should be large at same critical rotational speed and attachment rotational speed in the case of large Reynolds number. The gap spacing has an important role in changing the pattern of vortex shedding. It is very different in the mechanism of vortex shedding suppression for the flows around two rotating cylinders and single rotating cylinder.

关键词： flow around two rotating cylinders side-by-side arrangement measurement simulation vortex shedding suppression

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Poling Effects of Dielectric and Optical Properties on Pb(Zn1/3Nb2/3)1-xTixO3 Crystal

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Journal of Rare Earths 2006年第z1期24卷 166-168页

作者： tu Chi Shun wang Fu Tang Chien R R Hugo Schmidt V Chew L L Graduate Inst.of Applied Science and Engineering Fu Jen University Taipei 242 China Graduate Inst.of Applied Science and Engineering Fu Jen University Taipei 242 China Department of Physics Montana State University Bozeman MT 59717 USA Department of Physics Montana State University Bozeman MT 59717 USA Department of Mechanical Engineering National University of Singapore Singapore

Dipolar relaxation and dielectric/piezoelectric resonance in a (001)-cut Pb(Zn1/3Nb2/3)0.9Ti0.1O3 (PZNT10%) single crystal before and after electric (E)-field poling were presented. Dielectric permittivities were measured as functions of temperature, frequency and poling E-field strength. Frequency-dependent dielectric spectroscopy in the poled sample exhibits multiple piezoelectric resonances between 0.1 and 1 MHz, which can be described by the forced-damped-oscillator model. The resonant spectra show significant changes while phase transitions are taking place. The unpoled crystal shows almost no optical birefringence, indicating that the average structure symmetry is isotropic. Birefringence of the crystal is significantly enhanced by a prior E-field poling.

关键词： Pb(Zn1/3Nb2/3)1-xTixO3 dielectric permittivity phase transitions refractive indices

Effect of Different Protein Levels on Nutrient Digestion Metabolism and Serum Biochemical Parameters in Calves

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Agricultural Sciences in China 2008年第3期7卷 375-380页

作者： LI Hui DIAO Qi-yu ZHANG Nai-feng tu Yan wang Ji-feng Feed Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

The current study has been performed to examine the effects of different dietary protein levels on the growth, nutrient digestion and absorption, as well as biochemical parameters in calves. Nine healthy newborn calves were selected, randomly divided into 3 groups and fed 3 milk replacers with different protein levels （18, 22, and 26%）, respectively. Five period-digestion-metabolism trials were taken between 12-20, 22-30, 32-40, 42-50, and 52-60 days after birth. All 3 groups showed a similar growth curve during 11 to 61 experimental days, however, the growth rate of the 22% crude protein （CP） group was 8.89% higher than that of the 18% CP group and 19.48% higher than that of the 26% CP group, respectively. The apparent digestibility of dry material （DM） declined gradually with age, whereas, the apparent digestibility of N, extract ether （EE） rose slightly. Compared to the 22% CP and 26% CP group, calves fed with 18% CP apparently had a lower digestibility than DM, EE, and nitrogen （N）. The average apparent digestibilities of N were 69.39, 75.36, and 74.55%, respectively. Both the apparent digestibility and retention of calcium （Ca） and phosphorus （P） were steady throughout the experiment, but the average apparent digestibility of P in the 26% CP group was only 63.83%, which was markedly lower than that of the 18% CP group （70.40%） and 22% CP group （69.73%）. In addition, the serum concentrations of total protein （TP）, albumin （ALB）, and globulin （GLOB） of the 22% CP group were higher than those in the 18% CP and 26% CP groups. The urea N （BUN） content in the 18% CP group, on the other hand, was significantly lower than that of the other two groups. The highest glucose （GLU） concentration was found in the 22% CP group （5.38 mmol L^-1）, at the end of the trials. The protein levels in the milk replacer affected the digestion metabolism of nutrition and the serum biochemical parameters of calves at different physiological phases. Calves fed with 22% CP milk replacer had

关键词： calves protein levels milk replacer apparent digestibility biochemical parameters

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Laryngopharyngeal reflux disease management for recurrent laryngeal contact granuloma:A case report

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World Journal of Clinical Cases 2021年第8期9卷 1989-1995页

作者： Kai Li Wen-Yong Chen Yun-Ying Li tu-Lu wang Meng-Jia Tan Zong Chen Hai Chen Department of Otorhinolaryngology The Second Clinical College of Guangzhou University of Chinese MedicineGuangzhou 510000Guangdong ProvinceChina

BACKGROUND Laryngeal contact granuloma(LCG)is difficult to treat and frequently associated with high persistence and recurrence,despite the availability of both surgical and pharmacological treatment *** appropriate strategy is therefore needed to help patients with multiple recurrences of LCG to potentially avoid unnecessary *** SUMMARY We describe the case of a 34-year-old male patient with recurrent LCG in which a good response was achieved through successful management of laryngopharyngeal reflux disease using a combination pharmacotherapeutic regimen consisting of anti-reflux therapy,pepsin secretion inhibition,bile acid neutralization,and lifestyle *** patient underwent surgery to excise the granuloma,then relapsed,underwent a second surgery,which was followed by a second *** granuloma then disappeared after 9 mo of combined treatment with ilaprazole enteric-coated capsules(10 mg qd),mosapride tablets(5 mg tid)and compound digestive enzyme capsules(2 tablets).The drug regimen was discontinued after one year,and no recurrence of the lesion has been reported during the one-year follow-up *** We report a combination of pharmacotherapeutics and lifestyle modifications for the management of laryngopharyngeal reflux disease to address recurring LCG.

关键词： Recurrent laryngeal contact granuloma Laryngopharyngeal reflux disease management Anti-reflux therapy Pepsin secretion inhibition Bile acid neutralization Case report

Microstructure evolution and hot workability of in-situ synthesized Ti_(2)AlC/TiAl composite

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Transactions of Nonferrous Metals Society of China 2024年第12期34卷 3905-3918页

作者： Yu-peng wang Teng-fei MA Lei LI Long-long DONG wang-tu HUO Yu-sheng ZHANG Lian ZHOU Northwest Institute for Non-ferrous Metal Research Xi’an 710016China Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000China

The in-situ micro-nano Ti_(2)AlC particles reinforced TiAl(Ti_(2)AlC/TiAl)composite was fabricated using spark plasma *** hot workability of Ti_(2)AlC/TiAl composite was studied,and the effect of micro-nano particles on flow stress and dynamic recrystallization of composite was *** results showed that the micro-nano Ti_(2)AlC particles included strengthening and softening effects during hot deformation,resulting in the fact that the Ti_(2)AlC/TiAl composite exhibited a higher flow stress and more sufficient dynamic *** strengthening effect was mainly attributed to the Ti_(2)AlC particles induced refinement strengthening and hindered dislocation motion at the initial ***,the precipitation of nano-TiCr2 particles induced by stress concentration during hot deformation also contributed to higher flow stress via impeding dislocation ***,the refined microstructure and dislocation pile-up caused by micro-nano particles during deformation provided more nucleation sites for dynamic recrystallization,which significantly promoted the dynamic recrystallization of the second *** present results reveal that the Ti_(2)AlC/TiAl composite exhibited excellent hot workability,which is important to promote the application of TiAl alloys.

关键词： Ti_(2)AlC/TiAl composite spark plasma sintering hot deformation microstructure evolution dynamic recrystallization

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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Journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun wang Shuai wang Yan Li Libo Chen Handong Jiao Zhijing Yu Jiguo tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Semiconductor doping

Electrodeposition of zinc-cobalt alloys from chloride bath

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材料保护 1992年第11期 4-8页

作者： Harbin Institute of Technology Zhang Jingshuang Li Wenliang Yang Zhelong An Maozhong tu Zhenmi wang Zuobin

Zinc-cobalt alloys have been electrodeposited from a ammonia-free mild acidic electrolyte based on potassium chloride. And the passivation of Zn-Co alloy was also investigated. The temperature, current density, pH and cobalt content of the bath, all effect the cobalt content of the alloy deposit. Control of cobalt concentration and temperature (or C.D) of the bath were best for requlating the alloy composition, the properties of Zn-Co coating are found to be superior to those of zinc deposit, and especially, the corrosion resistance of Zn-Co alloy increases remarkably.

关键词： Electrodeposition of zinc-cobalt alloys from chloride bath Zn

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农民合作社与关联组织纵向协作的影响因素

华南农业大学学报（社会科学版） 2017年第1期16卷 54-65页

作者：王图展西南大学农村经济与管理研究中心重庆400716 西南大学经济管理学院重庆400716

从农民合作社的外部经济环境和自身条件角度分析其与关联组织纵向协作的影响因素,并基于381份合作社的大样本调查数据和计量经济模型进行实证检验。结果表明,大多数合作社与上下游关联组织存在非正式、松散的合作伙伴关系,但是订立正式... 详细信息

从农民合作社的外部经济环境和自身条件角度分析其与关联组织纵向协作的影响因素,并基于381份合作社的大样本调查数据和计量经济模型进行实证检验。结果表明,大多数合作社与上下游关联组织存在非正式、松散的合作伙伴关系,但是订立正式的书面契约、开展紧密型纵向协作的比例仍然偏低。整体而言,关联环节的交易费用、农产品产业链结构、合作社负责人能力及合作社的其他个体特征是合作社与关联组织开展纵向协作的重要影响因素,但具体到解释变量则因上下游关联环节、纵向协作形式的不同而存在统计显著性上的差异。

关键词：农民合作社上下游关联组织交易费用产业链结构个体特征

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Cloning, characterization and expression analysis of Ctenopharyngodon idella VDAC1 that is up-regulated in response to grass carp reovirus infection revealed by proteomic analysis

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Cloning, characterization and expression analysis of Ctenoph...