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Effects of temperature-gradient-induced damage of zirconia metering nozzles

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 999-1003页

作者： Liang Zhao qun-hu Xue College of Materials and Mineral Resources Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Techno-institute of Recycling Economy Xi’an 710055China

The effects of temperature-gradient-induced damage of zirconia metering nozzles were investigated through analysis of the phase composition and microstructure of nozzle samples. The analysis was carried out using X-ray diffraction and scanning electron microscopy after the samples were subjected to a heat treatment based on the temperatures of the affected, transition, and original layers of zirconia metering nozzles during the continuous casting of steel. The results showed that, after heat treatment at 1540, 1410, or 1300A degrees C for a dwell time of 5 h, the monoclinic zirconia phase was gradually stabilized with increasing heat-treatment temperature. Moreover, a transformation to the cubic zirconia phase occurred, accompanied by grain growth, which illustrates that the temperature gradient in zirconia metering nozzles affects the mineral composition and microstructure of the nozzles and accelerates damage, thereby deteriorating the quality and service life of the nozzles.

关键词： temperature gradient zirconia metering nozzles mineral composition microstructure damage mechanism

Effects of the precipitation of stabilizers on the mechanism of grain fracturing in a zirconia metering nozzle

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1041-1047页

作者： Liang Zhao qun-hu Xue Dong-hai Ding College of Materials and Mineral Resources Xi'an University of Architecture and TechnologyXi'an 710055China Shaanxi Techno-institute of Recycling Economy Xi'an 710055China

The mechanism of grain fracturing in a zirconia metering nozzle used in the continuous casting process was studied. The phase composition, microstructure, and chemical composition of the residual samples were studied using an X-ray fluorescence analyzer, scanning electron microscope, and electron probe. Results revealed that the composition, structure, and mineral phase of the original layer, transition layer, and affected layer of the metering nozzle differed because of stabilizer precipitation and steel slag permeation. The stabilizer MgO formed low-melting phases with steel slag and impure SiO2 on the boundaries（pores） of zirconia grains; consequently, grain fracturing occurred and accelerated damage to the metering nozzle was observed.

关键词： continuous casting metering nozzle partially stabilized zirconia grains fracture mechanisms electron probe microanalysis

Transient Appearance of Double Spontaneous-Snakes in EAST H Mode Plasma

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Chinese Physics Letters 2014年第3期31卷 96-98页

作者： XU Li-Qing hu Li-qun ZHANG Zi-Jun Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031

Transient lasting of double spontaneous snakes is observed in energy confinement improved plasma on the EAST tokamak. The destabilization of snakes with superb particle confinement can lower plasma energy confinement and slow plasma toroidal rotation. The non-monotonic q profile with double q=1 surface, slightly above unity in central, is constructed. The prevailing harmonic modes are susceptible to the nearly zero magnetic shear. Finally, the role of anomalous particle transport and the formation of off-axis peaking electron profile on the excitation of double snakes are discussed.

关键词： TOKAMAKS RESEARCH PLASMA (Ionized gases) -- Research PERTURBATION (Quantum dynamics) EXCITATION spectrum PHYSICS research

EXPERIMENTAL RESEARCH ON A SUPERCAVITATING SLENDER BODY OF REVOLUTION WITH VENTILATION

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Journal of Hydrodynamics 2002年第2期14卷 17-23页

作者： Feng, Xue-Mei Lu, Chuan-Jing hu, Tian-qun Dept. of Eng. Mech. Shanghai Jiaotong Univ. Shanghai 200240 China

The behavior of supercavitating and cavitatlng flow around a conical body of revolution with and without ventilation at several angles of attack was studied experimentally. The hydrodynamic forces for a range of cavitation number were measured. Comparisons of the appearance and the hydrodynamic forces in condition of cavity with and without ventilation were made over the same range of the cavitation number, and a well agreement was obtained. The changes of the drag were especially studied. The experimental results showed that the drag of the model decreased with the presence of supercavity under the ventilation condition.

关键词： Angle measurement Bodies of revolution Drag Force control Ventilation

A V-shaped spectroscopic cell for FTIR measurements

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Chinese Chemical Letters 2011年第4期22卷 481-484页

作者： Xiang Qin Lin Zhi Xiang Zhang Wan qun hu Department of Chemistry University of Science and Technology of China Hefei 230026 China

A V-shaped spacroscopic cell（V-cell） was constructed using two CaF2 optical plates for FTIR light transparent measurements in the range of 4000-1000 cm^（-1）.The spectrum of ethanol was characterized with the standard spectra,excellent fitting was achieved with a bottom-width correction *** principle of the V-cell was discussed,giving equations for the data *** shows that the V-cell is an auto-focus type spectroscopic cell,which can effectively avoid absorption saturation with amplifications for weak absorption *** V-cell design is simple and effective,easy to operate,suitable for applications in liquid samples with high absorption bands,willing to have broad application prospects.

关键词： V-shaped cell FTIR spectroscopy Light transparent Error correction Demountable Ethanol

Numerical study on variation characteristics of the unsteady bearing forces of a propeller with an external transverse excitation

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Journal of Hydrodynamics 2019年第2期31卷 400-412页

作者： Min-hua Shu Ke Chen Yun-xiang You Tian-qun hu Remfeng Wang State Key Laboratory of Ocean Engineering Collaboration Innovation Center for Advanced Ship and Deep-Sea Exploitation EquipmentShanghai JiaoTong UniversityShanghai 200240China

The unsteady bearing forces of a propeller can be significantly affected by external transverse *** paper numerically studies the unsteady variation characteristics of the bearing forces of a three-blade conventional propeller with external transverse excitations or without *** dynamic mesh method combined with the RANS turbulence model is *** numerical simulation shows the frequency response in the frequency domain of KT,Kq under external transverse *** frequency of the response is found always equal to twice of the excitation *** the amplitude of the external transverse excitation keeps constant,the amplitude of the response increases with the in crease of the excitation *** the excitation frequency keeps constant,the amplitude of the response increases with the increase of the excitation amplitude,in a power-law *** pressure distribution can be significantly affected by the external transverse excitation,leading to a high irregularity of the flow field.

关键词： External transverse excitation unsteady bearing forces excitation frequency propeller dynamic mesh method

Observation of Electron Fishbone-Like Instabilities in EAST Heavy Impurity Ohmic Plasma

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Chinese Physics Letters 2013年第7期30卷 124-126页

作者： XU Li-Qing hu Li-qun EAST team Institute of Plasma Physics Chinese Academy of SciencesHefei 230031

The transient burst of an internal kink mode is first observed in EAST heavy impurity ohmic *** features of the electron fishbone-like mode are presented,and the fishbone-like instabilities are found to be driven by the trapped supra-thermal *** processional frequency of the trapped supra-thermal electrons is calculated with different discharge *** results indicate that the calculated processional frequency is consistent with the experimental ***,we also find that the frequency chirping of the long-lived mode is related to the evolution of the safety factor profile.

关键词： parameters. profile. Electron

Influence of transitional nursing on the compliance behavior and disease knowledge of children with purpura nephritis

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World Journal of Clinical Cases 2020年第21期8卷 5213-5220页

作者： Li Li Li huang Ning Zhang Chun-Mei Guo Yan-qun hu Department of Pediatrics Hainan Provincial People's HospitalHaikou 570000Hainan ProvinceChina Department of Internal Medicine-neurology Hainan Provincial People's HospitalHaikou 570000Hainan ProvinceChina Department of Healthcare Center Hainan Provincial People's HospitalHaikou 570000Hainan ProvinceChina

BACKGROUND Purpura nephritis,also called Henoch-Schönlein purpura nephritis,is a systemic disease with small dead vasculitis as the main pathological *** To observe the influence of transitional nursing activities on the compliance behaviors and disease knowledge of children with purpura *** A total of 82 children with purpura nephritis were included and divided into a general nursing group(41 children)and transitional nursing group(41 children)using the envelope *** general nursing group received routine nursing care,while the transitional nursing group received transitional nursing *** behaviors,knowledge of the disease,and self-management ability of the two groups were evaluated after nursing care was *** The scores of four items(self-care ability,self-responsibility,health knowledge level,and self-concept)in the transitional nursing group were significantly higher than those in the general nursing *** Transitional nursing can directly improve the disease knowledge level and selfmanagement ability of children with purpura nephritis and effectively reduce complications.

关键词： Purpura nephritis Transitional nursing Self-management ability Compliance behavior Knowledge of the disease Comparative study

Study on the gamma rays and neutrons energy response optimization of a scintillating fiber detector for EAST with Geant4

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Nuclear Science and Techniques 2023年第9期34卷 40-49页

作者： Wei-Kun Chen Li-qun hu Guo-Qiang Zhong Rui-Jie Zhou Bing Hong Qiang Li Li Yang Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Institute of Energy Hefei Comprehensive National Science Center(Anhui Energy Laboratory)Hefei 230031China

A new scintillating fiber detector inside magnetic shielding tube was designed and assembled for use in the next round of fusion experiments in the experimental advanced superconducting tokamak to provide D–T neutron yield with time *** this study,Geant4 simulations were used to obtain the pulse height spectra for ideal signals produced when detecting neutrons and gamma rays of multiple *** of the main sources of interference was found to be low-energy neutrons below 10–5 MeV,which can generate numerous secondary particles in the detector components,such as the magnetic shielding tube,leading to high-amplitude output *** address this issue,a compact thermal neutron shield containing a 1-mm Cd layer outside the magnetic shielding tube and a 5-mm inner Pb layer was specifically *** effects on the measurement of fast neutrons and the shielding effect on gamma rays were *** can suppress the height of the signals caused by thermal neutrons to a level below the height corresponding to neutrons above 4 MeV because the yield of the latter is used for detector *** addition,the detector has relatively flat sensitivity curves in the fast neutron region,with the intrinsic detection efficiencies(IDEs)of approximately 40%.For gamma rays with energies that are not too high(<8 MeV),the IDEs of the detector are only approximately 20%,whereas for gamma rays below 1 MeV,the response curve cuts off earlier in the low-energy region,which is beneficial for avoiding counting saturation and signal accumulation.

关键词： Sci-Fi detector D–T fusion neutron Thermal neutron shield Energy response Geant4