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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

Serum anti-aquaporin 4 antibody in neuromyelitis patients is not correlated with the length of injured spinal cord segments

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Neural Regeneration Research 2011年第35期6卷 2725-2731页

作者： Shirong Li Lan Chu Shuai Dong Hui Yu Zhu xu hao wang Department of Neurology Affiliated Hospital of Guiyang Medical College Guiyang 550004 Guizhou Province China

Clinical information and serum samples of 20 neuromyelitis patients and 30 patients with multiple sclerosis were collected in this study. The expression of anti-aquaporin 4 antibody in the serum of all patients was detected with an indirect immunofluorescence assay, using human embryonic kidney 293 cell line that stably express human-derived aquaporin 4 as a substrate. The characteristics of head and spinal magnetic resonance imaging were also observed in patients who had neuromyelitis and were positive for anti-aquaporin 4 antibody. Results showed that the expression of anti-aquaporin 4 antibody was significantly different between multiple sclerosis patients and neuromyelitis patients. There were 13 out of 20 neuromyelitis patients （including high-risk syndrome） that were positive for anti-aquaporin 4 antibody. The magnetic resonance imaging examinations of the head and spinal cord found that among the 13 positive patients, nine cases showed normal cerebral hemisphere and optic nerve, two cases had optic nerve changes, and one case had an atypical lesion in the brain. All 30 multiple sclerosis patients were negative for this antibody. The experimental findings indicate that patients with neuromyelitis optica had more than three lesioned segments in the spinal cord by magnetic resonance imaging, and the segment length of the injured spinal cord was not associated with the titer of aquaporin 4 antibody in neuromyelitis patients.

关键词： neuromyelitis optica multiple sclerosis aquaporin 4 antibody magnetic resonance imaging neural regeneration

Relationship between dietary niacin intake and erectile dysfunction:a population-based study

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Asian Journal of Andrology 2024年第4期26卷 382-388页

作者： Wei-Long Lin Cheng Zheng hao-xu wang Wei Zhang Ming-En Lin Department of Urology The First Affiliated Hospital of Shantou University Medical CollegeMedical College of Shantou UniversityShantou 515041China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou 510260China.

Existing research on the precise link between dietary niacin intake and erectile dysfunction(ED)is ***,this study aimed to investigate the potential association between dietary niacin intake and the risk of *** logistic regression and restricted cubic splines(RCSs)were used to examine the relationship between dietary niacin intake and *** interaction analysis was performed to assess the impact of different subgroups on the study *** addition,1:1 propensity score matching(PSM)was employed to adjust for potential confounding factors,ensuring the reliability of the *** analyzed data were collected from the 2001–2004 National Health and Nutrition Examination Survey(NHANES)in the *** study encompassed 3184 adults,among whom 863 participants were identified as having *** adjustments for potential confounders,the findings revealed that higher niacin intake,specifically in the highest tertile,was associated with a decreased risk of ED compared to that in the lowest tertile,showing an odds ratio(OR)of 0.56(95%confidence interval[CI]:0.37–0.85).Analysis of dose–response curves illustrated a negative correlation between dietary niacin intake and the risk of *** and interaction analyses fortified the consistency of these ***,PSM corroborated the validity of the *** study suggests an inverse association between dietary niacin intake and the risk of ***,establishing a cause-and-effect relationship remains elusive,and defining the safe threshold of niacin intake to prevent ED requires further investigation.

关键词： dietary niacin erectile dysfunction National Health and Nutrition Examination Survey propensity score matching

Case Report:A case of chylothorax treated curatively with Sapylin, a streptococcus preparation

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第12期8卷 885-887页

作者： xu Zhi-hao wang Chun-fu ZHANG Yue-qin SHEN Hua-hao xu Feng Department of Respiratory Diseases the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

Chylothorax is an uncommon disease where fatty fluid accumulates within the chest cavity. Conservative manage- ment, including repeated thoracentesis or pleurodesis, seems to be suitable to most cases. Herein, we present a case of efficacious pleurodesis by intrapleural injection of Sapylin, a streptococcus preparation, for the treatment of chylothorax. A 52-year-old non-smoking female farmer was diagnosed as idiopathic chylothorax after we ruled out possible causes including chest trauma, lymphoma, lung cancer, filariasis, tuberculosis, and etc. Two-time intra-thoracic injection of 3 Klinische Einheit (KE) Sapylin achieved rapid and effective control of chylothorax with no severe side effects. Sapylin may facilitate pleurodesis by producing a strong inflammatory response.

关键词： Chylothorax Sapylin Streptococcus preparation

Intermolecular interactions induced property improvement for clean fracturing fluid by deep eutectic solvents

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Petroleum Science 2023年第6期20卷 3540-3552页

作者： Xiang-Yu wang Ming-Wei Zhao xu-hao wang Peng Liu Meng-Yao Fan Teng Li Zhen-Feng Ma Ying-Jie Dai Cai-Li Dai Key Laboratory of Unconventional Oil&Gas Development China University of PetroleumQingdao266580ShandongPR China Shandong Key Laboratory of Oilfield Chemistry China University of PetroleumQingdao266580ShandongPR China Dongxin Oil Production Plant Ying First Management Zone of Sinopec Shengli Oilfield Company Dongying257002ShandongPR China

Fracturing fluid property play a critical role in developing unconventional *** eutectic solvents(DESs)show fascinating potential for property improvement of clean fracturing fluids(CFFs)due to their low-price,low-toxicity,chemical stability and flexible *** this work,DESs were synthesized by mixing hydrogen bond acceptors(HBAs)and a given hydrogen bond donor(HBD)to explore their underlying influence on CFF properties based on the intermolecular *** hydrogen-bonding,van der Waals and electrostatic interactions between DES components and surfactants improved the CFF properties by promoting the arrangement of surfactants at interface and enhancing the micelle network *** HBD enhanced the resistance of CFF for Ca^(2+) due to coordination-bonding *** DESs composed of choline chloride(ChCl)and malonic acid show great enhancement for surface,rheology,temperature resistance,salt tolerance,drag reduction,and gel-breaking performance of *** DESs also improved the gel-breaking CFF-oil interactions,increasing the imbibition efficiencies to 44.2%in 74 *** HBAs can effectively strengthen the intermolecular interactions(e.g.,HBA-surfactant and HBD-surfactant interactions)to improve CFF *** DESs developed in this study provide a novel strategy to intensify CFF properties.

关键词： Deep eutectic solvents(DESs) Clean fracturing fluids(CFFs) Intermolecular interactions Property improvement

Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 58-69页

作者： Jie wang Wei wang xuheng Chen Junfang Bao Qiuyue hao Heng Zheng Runsheng xu School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Institue of Ironmaking Technology Baosteel Central Research InstituteShanghai 201999China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The utilization of iron coke provides a green pathway for low-carbon *** uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was ***,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric *** findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and *** provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron *** the heating rate in non-isothermal gasification can enhance the reactivity of iron *** metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon *** kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore ***,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.

关键词： low-carbon ironmaking iron coke gasification structural evolution kinetic model

Determining soil redistribution in Dian Lake catchment by combined use of caesium-137 and selected chemical properties

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Ecological Economy 2009年第1期5卷 91-100页

作者： Zhang Mingli Yang hao xu Congan wang Yihong College of Geography Science Nanjing Normal University Nanjing 210046 P. R： China

Recent development in the use of the environmental radionuclide caesium-137 for documenting rates and soil redistribution on the cultivated or uncultivated land and estimating rates of sediment deposition on represents an important advance that overcomes many of the limitations of the conventional techniques commonly applied in such investigations. A study on soil redistribution （including soil erosion and deposition） was carried out in the Dian Lake catchment, Yunnan Province, using ^137Cs and selected chemical properties. The average soil erosion rate was 1,280.2 t km^2 yr^-1. Soil erosion rate occurring on different parts of the slope was significantly different on different parts of the slope, *** the top. the bottom to the middle slope. The average soil erosion rate is also different with the land use type and that of the cultivated land （1, 672. 8 t km^-2 yr^-1） is higher than oJ the uncultivated land （1.161.2t km^-2 yr^-1 ）. The result shows that landform, slope gradient and land use type are key factors that influence the size of soil erosion. In addition, we also find the SOC and TN contents and amount of the soil erosion to be correlated in the soil. With the soil erosion occurring, there are land degradation and the local eco-environmental problems, such as water eutrophication in Dian Lake.

关键词： ^137 - Cs SOC TN soil redistribution Dian Lake catchment

Influence of the low-frequency source parameters on the plasma characteristics in a dual frequency capacitively coupled plasma reactor:Two dimensional simulations

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Progress in Natural Science:Materials International 2009年第6期19卷 677-684页

作者： Xiang xu, hao Ge, Shuai wang, Zhongling Dai, Younian wang , Aimin Zhu State Key Lab of Materials Modification by Electron, Ion and Laser Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023, China State Key Lab of Materials Modification by Electron Ion and Laser Beams School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116023 China

A two-dimensional (2D) fluid model is presented to study the discharge of argon in a dual frequency capacitively coupled plasma (CCP) reactor. We are interested in the influence of low-frequency (LF) source parameters such as applied voltage amplitudes and low frequencies on the plasma characteristics. In this paper, the high frequency is set to 60 MHz with voltage 50 V. The simulations were carried out for low frequencies of 1, 2 and 6 MHz with LF voltage 100 V, and for LF voltages of 60, 90 and 120 V with low frequency 2 MHz. The results of 2D distributions of electric field and ion density, the ion flux impinging on the substrate and the ion energy on the powered electrode are shown. As the low frequency increases, two sources become from uncoupling to coupling. When two sources are uncoupling, the increase in LF has little impact on the plasma characteristics, but when two sources are coupling, the increase in LF decreases the uniformities of ion density and ion flux noticeably. It is also found that with the increase in LF voltage, the uniformities in the radial direction of ion density distribution and ion flux at the powered electrode decreases significantly, and the energy of ions bombarding on the powered electrode increases significantly.

关键词： Dual frequency Capacitively coupled plasma Fluid simulation

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大直径泥水平衡盾构浅覆土始发地表沉降特性

铁道工程学报 2018年第12期35卷 36-40,69页

作者：刘方崔建徐汪豪高峰重庆交通大学重庆400074 西南交通大学成都610031

研究目的:在盾构始发阶段,由于覆土浅、地层自稳能力差,地层扰动引起的危害已成为不可忽视的问题。基于此,本文以京张高铁清华园隧道工程为背景,依据始发段实际加固方案及现场监测得到的始发段掘进参数,采用有限差分法建立三维泥水平衡... 详细信息

研究目的:在盾构始发阶段,由于覆土浅、地层自稳能力差,地层扰动引起的危害已成为不可忽视的问题。基于此,本文以京张高铁清华园隧道工程为背景,依据始发段实际加固方案及现场监测得到的始发段掘进参数,采用有限差分法建立三维泥水平衡盾构隧道数值模型,通过分析始发施工过程中隧道周边地表土体位移,并与现场实测进行对比,研究大直径盾构浅覆土始发段地层位移变化特征。研究结论:(1)数值计算与现场监测结果得到的土体位移规律基本一致,验证了本文盾构法施工数值模拟计算方法的工程实用价值;(2)由于始发竖井端头进行了高压旋喷桩加固,相应的地表沉降明显得到控制改善,印证了加固方案的有效性;(3)得到了大直径泥水盾构浅覆土始发土体变形规律:隧道轴线上方土体的沉降位移最大,为20 mm,两侧逐渐减小,两端呈现轻微上拱趋势,隧道周围土体有向洞室挤人运动的趋势;(4)该研究成果可为类似大直径盾构浅覆土始发工程提供参考。

关键词：泥水平衡盾构土体改良加固浅覆土始发现场监测数值模拟地表沉降