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Experimental research on the contact force of the bi-directional pig in oil and gas pipeline

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Petroleum Science 2023年第1期20卷 474-481页

作者： Xiao-Xiao Zhu Chun-Ming Fu yu-tao Wang shi-Ming Zhang College of Mechanical and Transportation Engineering China University of Petroleum-BeijingChangpingBeijing102249China

The migration process of the pig in oil and gas pipeline is a complex dynamic *** the pigging operation,the variation of friction force caused by the nonlinear contact between the sealing disc and the pipe wall is the key factor affecting the dynamic characteristics of the pig *** present,the existed pigging models for predicting pigging behavior regard friction as an invariant *** research indicates that the friction force of the pig varies with the contact force and the lubrication ***,the assumption that the friction force is constant cannot reflect the friction dynamic characteristics of the pig during pigging,and will also affect the accuracy of the pigging *** the variation of friction force of pig under different conditions is the basis of establishing the transient dynamic model of a *** a result,in this paper,a method of direct measurement of contact force between the pig and the pipeline is presented,the contact force,the friction force,as well as the friction coefficient of the pig are obtained from the *** results in this paper can help to establish a more accurate dynamic model of pig.

关键词： Pipeline pig Sealing disc Contact force Friction coefficient Experimental rig

Unexpected phenotypes of malformations induced in Xenopus tropicalis embryos by combined exposure to triphenyltin and 9-cis-retinoic acid

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Journal of Environmental Sciences 2014年第3期26卷 643-649页

作者： Jingmin Zhu Lin yu Lijiao wu Lingling Hu Huahong shi State Key Laboratory of Estuarine and Coastal Research East China Normal University Key Laboratory of Urbanization and Ecological Restoration Department of Environmental Science East China Normal University

Xenopus tropicalis embryos were exposed for 48 hr to the mixtures of 5 μg Sn/L triphenyltin （TPT）, which is a well-known endocrine disruptor, and 0.25-5 μg/L 9-cis retinoic acid （9c-RA）, which is the natural ligand of retinoid X receptor. The phenotypes induced by combined exposure were more variable than those resulting from single exposure to either TPT or 9c-RA. The prominent phenotypes included underdeveloped head structures, abnormal eyes, narrow fins, enlarged proctodaeum, etc. Especially, combined exposure induced unexpected notochord malformations, which ranged from small swellings of the surface of the tails to the extension and extrusion of notochord out of the posterior tails. Compared with the 5 μg Sn/L TPT-treated group, the index of fin deficiency was not affected, and the index of axis deficiency was significantly increased with increasing RA concentrations in the mixtures. Our results suggest that combined exposure to TPT and 9c-RA induced not only more variable phenotypes of malformations than exposure to single compound but also some new and unexpected phenotypes.

关键词： Xenopus tropicalis embryos triphenyltin teratogenicity retinoic acid notochord

Influence of filler morphology on percolation threshold of isotropical conductive adhesives (ICA)

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Science China(Technological Sciences) 2012年第1期55卷 28-33页

作者： tao yu YANG ZhenGuo LU XiaoLu tao GuoLiang XIA YanPing wu HaiPing Department of Materials Science Fudan University Shanghai 200433 China Department of Materials Science and Engineering Changzhou University Changzhou 213614 China

Different aspect ratio silver nano-structured materials including nanocubes,nanorods and nanowires were prepared by micro-waved assisted glycol reduction *** characterization methods including SEM and XRD were processed on these *** conductive adhesives(ICA) were developed by using these Ag nanomaterials as conductive *** was found that the conductivity and thermal conductivity percolation threshold of the ICA depended on the morphologies of the fillers,lower percolation threshold could be obtained by using higher aspect ratio filler.A modified percolation threshold theory was put forward to explain and simulate the experiment results,the simulated results could match the experiment results very well.

关键词： ICA percolation threshold aspect ratio simulation

Study of 0.9Al_2O_3–0.1TiO_2 ceramics prepared by a novel DCC-HVCI method

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Journal of Advanced Ceramics 2018年第2期7卷 152-159页

作者： Jia-Min wu Huan XIAO Meng-yue LIU Ying CHEN Yi-Xin MA Li-Jin CHENG yu-Sheng shi State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and EngineeringHuazhong University of Science and Technology

In this paper, in-situ coagulation of 0.9Al_2O_3–0.1TiO_2 suspension and microwave dielectric properties of 0.9Al_2O_3–0.1TiO_2 ceramics prepared by a novel direct coagulation casting via high valence counter ions(DCC-HVCI) method were proposed. The 0.9Al_2O_3–0.1TiO_2 suspension could be coagulated via controlled release of calcium ions from calcium iodate at an elevated temperature. The influence of tri-ammonium citrate(TAC) content, solid loading, and calcium iodate content on the rheological properties of the suspension was investigated. In addition, the influence of coagulation temperature on coagulation time and properties of green bodies was also studied. It was found that the stable 0.9Al_2O_3–0.1TiO_2 suspension could be successfully prepared by adding 0.3 wt% TAC and adjusting pH value to 10–12 at room temperature. 0.9Al_2O_3–0.1TiO_2 green bodies with uniform microstructures were coagulated by adding 8.0 g/L calcium iodate after treating at 70 ℃ for 1 h. 0.9Al_2O_3–0.1TiO_2 ceramics, sintered at 1500 ℃ for 4 h and annealed at 1100 ℃ for 5 h, showed uniform microstructures with density of 3.62±0.02 g/cm^3. The microwave dielectric properties of 0.9Al_2O_3–0.1TiO_2 ceramics prepared by DCC-HVCI method were: ε_r = 11.26±0.06, Q×f = 11569± 629 GHz, τ_t = 0.93±0.60 ppm/℃. The DCC-HVCI method is a novel and promising route without binder removal process to prepare complex-shaped microwave dielectric ceramics with uniform microstructures and good microwave dielectric properties.

关键词： rheological properties microwave dielectric properties 0.9Al2O3–0.1TiO2 DCC-HVCI

Experimental and Numerical Study on the Bubble Dynamics near Two-Connected Walls with An Obtuse Angle

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China Ocean Engineering 2020年第6期34卷 828-839页

作者： LI shi-min CUI Pu ZHANG Shuai LIU Wen-tao PENG yu-xiang College of shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China

This study is concerned with the dynamic characteristics of bubbles near two connected walls(one horizontal and the other inclined with an obtuse angle from the horizontal one). In this study, we set up an experiment system to conduct typical cases, and the boundary element method is employed to explain the bubble behavior and study the effect of relative parameters. Comparing the two mutually perpendicular walls, we find that the liquid jet deviates from the horizontal direction within a much shorter range. On the intersection of the two walls, the motions of bubbles have similar trends. The relatively low pressure between the bubble and walls causes the transition of the bubble, and a local high-pressure zone leads to the formation of a liquid jet. Moreover, there are moments when the two walls are evenly stressed in the first bubble cycle. Through parameter analysis, we find that the jet directions of bubbles perform interesting discrepancies for different buoyancy and distances to walls. Some instructive conclusions are given to serve practical applications.

关键词： bubble dynamics solid walls liquid jets

600-MW_(e)high-temperature gas-cooled reactor nuclear power plant HTR-PM600

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Nuclear Science and Techniques 2022年第8期33卷 69-76页

作者： Zuo-Yi Zhang yu-Jie Dong Qi shi Fu Li Hai-tao Wang Institute of Nuclear and New Energy Technology of Tsinghua University Collaborative Innovation Center of Advanced Nuclear Energy TechnologyThe Key Laboratory of Advanced Reactor Engineering and SafetyMinistry of EducationBeijing 100084China Chinergy Co.Ltd Beijing 100193China

The HTR-PM600 high-temperature gas-cooled reactor nuclear power plant is based on the technology of the high-temperature gas-cooled reactor pebble-bed module(HTR-PM)demonstration *** utilizes proven HTR-PM reactor and steam generator modules with a thermal power of 250 MW_(th)and power generation of approximately 100 MW_(e)per *** modules in parallel,connected to a steam turbine,form a 600-MW_(e)nuclear power *** addition,its system configuration in the nuclear island is identical to that of the HTR-PM in which the technical risks are *** this principle,the HTR-PM600 achieves the same level of inherent safety as the *** concept of a ventilated lowpressure containment(VLPC)is unchanged;however,a large circular VLPC accommodating all six reactor modules is adopted rather than the previous small-cavity-type VLPC,which contains only one module,as defined for the *** layout of the nuclear island and its associated systems refer to single-unit pressurized water reactor(PWR)*** this layout,the HTR-PM600achieves a volume size of the nuclear island that is comparable to a domestic PWR of the same power *** will be a GenerationⅣnuclear energy technology that is economically competitive.

关键词： High-temperature gas-cooled reactor Module HTR-PM600 GenerationⅣ

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磁场下碳化物析出的热力学机制

原子与分子物理学报 2025年第4期42卷 121-130页

作者：廖已莹侯廷平杨雨豪郑一航于涛刘伍明吴开明武汉科技大学理学院武汉430081 冶金工业过程系统科学湖北省重点实验室武汉430081 省部共建耐火材料与冶金国家重点实验室武汉430081 江汉大学光电材料与技术学院光电化学材料与器件教育部重点实验室武汉430056 中国科学院物理研究所北京100190

钢中碳化物的形成主要由合金元素的种类以及含量的决定,碳化物对钢铁材料的显微组织形态和力学性能有重要影响.磁场是影响碳化物析出规律发生改变的重要因素之一.以常见的碳化物M_(6)C(M=Fe,Mo)作为研究对象,利用第一性原理计算η-Fe_(... 详细信息

钢中碳化物的形成主要由合金元素的种类以及含量的决定,碳化物对钢铁材料的显微组织形态和力学性能有重要影响.磁场是影响碳化物析出规律发生改变的重要因素之一.以常见的碳化物M_(6)C(M=Fe,Mo)作为研究对象,利用第一性原理计算η-Fe_(2)C、Fe_(3)C、Fe_(2)Mo_(4)C、Fe_(3)Mo_(3)C-Ⅰ、Fe_(3)Mo_(3)C-Ⅱ和Fe_(4)Mo_(2)C等合金碳化物的磁矩,计算结果表明其中Fe_(4)Mo_(2)C的磁矩最大,达到了7.04μB.磁矩不仅由碳化物晶胞中Fe原子个数有关,还与Fe Wyckoff占位紧密相关.通过模拟计算碳化物的磁致磁热熔、磁熵、磁焓和磁自由能,从热力学角度对各碳化物进行分析,结果表明磁场会使碳化物的磁致磁热熔和磁熵增加;强磁场会降低M_(6)C的磁自由能进而提高其稳定性.此工作为研究核聚变材料磁性能提供理论基础和技术参考.

关键词：磁场碳化物析出相热力学机制

Sorption of Am(Ⅲ) on Na-bentonite:Effect of pH,ionic strength,temperature and humic acid

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Chinese Chemical Letters 2012年第10期23卷 1189-1192页

作者： tao yu Wang Suo wu Qiao Hui Fan Radiochemistry Laboratory School of Nuclear ScienceTechnologyLanzhou UniversityLanzhou 730000China College of Chemistry BiologyMaterials ScienceEast China Institute of TechnologyFuzhou 344000China

Sorption of Am（III） on Na-bentonite as a function of contact time, pH, ionic strength, humic acid （HA） and temperature was investigated under ambient conditions. The results showed that the sorption was strongly dependent on pH and ionic strength. Am（III） sorption Can be described well by pseudo-second-order model. The presence of HA takes a positive effect at low pH; but a negative influence under high pH range. Enthalpy, entropy and Gibbs free energy （i.e., △H0, △S0 and △G0） calculated from sorption isotherms suggested that sorption process of Am（III） was spontaneous and endothermic.

关键词： Sorption Am(III) Bentonite Humic acid

CsI-bowl:an ancillary detector for exit channel selection inγ-ray spectroscopy experiments

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Nuclear Science and Techniques 2023年第9期34卷 32-39页

作者： Xing-Chi Han Shuo Wang Hong-Yi wu Zhi-Huan Li Guo-Zhu shi Ruo-Fu Chen yue-Zhao Zhang Shou-yu Wang Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China WeiHai Research Institute of Industrial Technology of Shandong University Weihai 264209China School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Institute of Modern Physics Chinese Academy of SciencesLanzhou 73000China

A particle detector array designed for light-charged particles, known as the CsI-bowl, was built for exit channel selection for in-beam γ-ray spectroscopy experiments. This device is composed of 64 CsI(Tl) detectors, organized in a structure reminiscent of a tea-bowl. High quantum efficiency photodiodes, characterized by their minimal mass, were employed to collect scintillation light. Its design, construction, particle identification resolution, and its effectiveness in relation to exit channel selection are described in this paper. In source tests, the optimal figure of merit for the identification of α-particles and γ-rays using the charge comparison method was found to be 3.3 and 12.1 for CsI detectors coupled to photodiodes and avalanche photodiodes, respectively. The CsI-bowl demonstrated effectiveness in identifying particles, specifically the emission of protons and α-particles in the58Ni(19F, xpyn) fusion–evaporation reaction, thereby enabling the selection of the desired exit channels.

关键词： Light charged particle detector array Particle identification Charge comparison method