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Effects of argon blowing at tundish upper nozzle on multiphase flow behavior in nozzle

Journal of Iron and Steel Research International 2022年第4期29卷 588-600页

作者： Xu-feng Qin Chang-gui Cheng yang Li Wei-li Wu yan jin The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina

In continuous casting,the argon blowing at the tundish upper nozzle is usually used to prevent nozzle clogging,whose effect is closely related to the migration of argon bubbles and the flow behavior of the liquid steel in the ***,to investigate the effects of argon blowing at the tundish upper nozzle on multiphase flow behavior in nozzle,a threedimensional model of the tundish–nozzle–mold was established for numerical *** results indicate that the argon bubbles injected from the inner wall of the tundish upper nozzle first move downward along the nozzle wall under the action of the liquid *** the distance from the tundish upper nozzle increases,the argon bubbles gradually diffuse to the center of the *** with no argon blowing,the liquid steel velocity increases in the center of the nozzle and decreases near the wall with argon *** increasing the argon flow rate,the concentration of bubbles in the nozzle increases,and the process of bubble group diffusion to the center region of the nozzle speeds *** in turn increases the liquid steel velocity at the center of the nozzle but reduces near the *** increasing the casting speed,the concentration of bubbles in the nozzle decreases,the length of the bubble group near the nozzle wall is extended,and the liquid steel velocity at the center region and near-wall region of the nozzle *** mechanism of argon blowing at the tundish upper nozzle to prevent nozzle clogging is mainly realized by the isolation effect of the argon bubble group on the inner wall of the nozzle.

关键词： Argon blowing Tundish upper nozzle Nozzle clogging Numerical simulation

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Incidence of gastroesophageal reflux disease in Uygur and Han Chinese adults in Urumqi

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World Journal of Gastroenterology 2012年第48期18卷 7333-7340页

作者： Chun-yan Niu Yong-Li Zhou Rong yan Ni-La Mu Bao-Hua Gao Fang-Xiong Wu jin-yan Luo Department of Gastroenterology First Affiliated Hospital of Xi'an Medical College Department of Cadre Wards First Affiliated Hospital of Xinjiang Medical University Department of Gastroenterology Second Affiliated Hospital of Xi'an Jiaotong University School of Medicine

AIM:To investigate the incidence of gastroesophageal reflux disease(GERD) and its related risk factors in Uygur and Han Chinese adult in Urumqi,***:A population-based cross-sectional survey was undertaken in a total of 972 Uygur(684 male and 288 female) aged from 24 to 61 and 1023 Han Chinese(752 male and 271 female) aged from 23 to 63 *** participants were recruited from the residents who visited hospital for health examination from November 2011 to May *** participant signed an informed consent and completed a GERD questionnaire(GerdQ) and a lifestyle-food frequency questionnaire *** whose Gerd Q score was ≥ 8 and met one of the following requirements would be enrolled into this research:(1) being diagnosed with erosive esophagitis(EE) or Barrett's esophagus(BE) by endoscopy;(2) negative manifestation under endoscopy(non-erosive reflux disease,NERD) with abnormal acid reflux revealed by 24-h esophageal pH monitoring;and(3) suffering from typical heartburn and regurgitation with positive result of proton pump inhibitor ***:According to Gerd Q scoring criteria,340 cases of Uygur and 286 cases of Han Chinese were defined as *** incidence in Uygur was significantly higher than in Han Chinese(35% vs 28%,χ2 = 11.09,P < 0.005),Gerd Q score in Uygur was higher than in Han Chinese(7.85 ± 3.1 vs 7.15 ± 2.9,P < 0.005),and Gerd Q total score in Uygur male was higher than in female(8.15 ± 2.8 vs 6.85 ± 2.5,P < 0.005).According to normalized methods,304(31%) cases of Uygur were diagnosed with GERD,including 89 cases of EE,185 cases of NERD and 30 cases of BE;256(25%) cases of Han Chinese were diagnosed with GERD,including 90 cases of EE,140 cases of NERD and 26 cases of *** incidence in Uygur was significantly higher than in Han Chinese(31% vs 25%,χ2 = 9.34,P < 0.005) while the incidences were higher in males of both groups than in females(26% vs 5% in Uygur,χ2 = 35.95,P < 0.005,and 19.8% vs 5.2% in Han,χ2 = 5.48,P < 0.02

关键词： Gastroesophageal reflux disease Incidence Uygur Han Risk factors Urumqi

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Photovoltaic properties of MEH-PPV/TiO_2 nanocomposites

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Chinese Science Bulletin 2008年第18期53卷 2743-2747页

作者： LI yan HOU yanBing jin Hui SHI QuanMin WANG yan FENG ZhiHui Key Laboratory of Luminescence and Optical Information Ministry of Education of China Institute of Optoelectronic Technology Beijing Jiaotong University Beijing 100044 China

Photovoltaic properties of photodiodes based on nano-TiO_2 and poly[2-methoxy,5-(2′-ethlhexyloxy)- p-phenylenevinylene] (MEH-PPV) composites are investigated. By comparing composite devices with the same weight of TiO_2 (nanoparticles and nanotubes):MEH-PPV, it was found that the device with TiO_2 nanotubes exhibited better performance. By further optimizing the weight radio of TiO_2 nano- tubes:MEH-PPV, we gained the device with a short circuit current density of 9.27 μA/cm2 with a light intensity of 16.7 mW/cm2 at the 500 nm wavelength, the highest open-circuit voltage of 1.1 V, and a photosensitivity of 332 at reverse bias of -0.6 V. The photosensitivity is improved by a factor of 33 compared with the undoped MEH-PPV device.

关键词：太阳能电池氧化硅纳米管 MEH-PPV 纳米复合材料

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Improved Removal Efficiency of Submicron Inclusions in Non-oriented Silicon Steel during RH Process

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Journal of Wuhan University of Technology(Materials Science) 2020年第6期35卷 1122-1127页

作者： CHEN Tianying jin yan CHENG Zhaoyang YUAN Zexi BI Yunjie LIU jing The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China

To improve the removal efficiency of such submicron inclusions,we designed an argon blowing method for an RH facility based on mathematical *** effect of the argon blowing on the liquid steel flow and the movement of submicron inclusions was studied using the k-ε flow model coupled with the DPM model for inclusion movement based on fluid computational dynamics in *** was found that a more uniform argon flow can be achieved in the up-leg snorkel with a new nozzle position and inner diameter,which resulted in a favorable up-lifting and mixing *** new design also increased the circulation rate of molten steel in the RH *** increased turbulent kinetic energy and turbulent dispersing rate enhanced the collision probability of submicron inclusions,which results in an improved removal for 0.5-1 μm *** proposed RH facility could increase the removal rate of submicron inclusions from the original 57.1% to 66.4%,which improves the magnetic properties of non-oriented silicon steel.

关键词： RH treatment argon blowing method model optimization submicron inclusions numerical simulation

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Spin Assignment of the First Discovered Superdeformed Band 152Dy(1) and Some Superdeformed Bands in Neighboring Nuclei

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Chinese Physics Letters 1999年第9期16卷 632-634页

作者： LIU Shu-xin XIN Xiao-bin ZENG jin-yan Department of Physics Peking Universityj Beijing 100871

By using various approaches to the spin assignment, including the best-fit-method, the variation of moment of inertia with angular momentum, the bandhead moment of inertia J0 systematics, and the signature systematics, the spin of the lowest level observed in the first discovered superdeformed band 152Dy(1)is definitely predicted to be I0 = 26(Eγ(I0 + 2 → I0) = 602.4 keV), rather than the previously predicted I0 = 22,24, or 25. The spin prediction and properties of some superdeformed bands in the A ~ 150 region are discussed.

关键词： inertia momentum signature

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‘One Health' for the people of Hong Kong and the world

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Science China(Life Sciences) 2016年第10期59卷 1068-1070页

作者： Kin-Hang Kok Hei-Man Vincent Tang Dong-yan jin Department of Biochemistry University of Hong Kong

Translational medicine refers to the conversion of scientific discoveries into improvements in medical practice. ＇From bench to bedside and back＇ is a phrase that is often used to describe the two-way information flow in translational medicine. On one hand, scientists working at the bench make new discoveries that enable clinicians to revolutionize patient care, while on the other hand, clinical investigations at the bedside provide new knowledge about diseases, which stimulate basic research at the bench.

关键词：世界香港健康科学发现临床医生临床调查基础研究信息流

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Flow and heat transfer of liquid slag in a continuous casting mold

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Journal of Iron and Steel Research International 2019年第9期26卷 926-940页

作者： Hai-biao Lu Chang-gui Cheng yang Li Xu-feng Qin yan jin The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina

A three-dimensional mathematical model for coupled liquid steel and liquid slag was established to study the flow and heat transfer behavior of liquid slag. Based on the volume of fluid method and the heat transfer model, the effect of different casting parameters on the flow and heat transfer of the liquid slag was investigated. The results show that there are two different size recirculation zones of the liquid slag layer on the liquid steel in the mold center plane, extending from the submerged entry nozzle to the mold narrow face. With the increase in the casting speed and the decrease in the viscosity of the mold flux, the overall velocity and the temperature of the liquid slag increase. With the increase in the inclination angle and the submergence depth of the submerged entry nozzle, the temperature of the liquid slag decreases, and the velocity decreases near the mold narrow face and increases in the vicinity of the submerged entry nozzle. The inactive flow field and the low temperature of liquid slag within 100 mm of the submerged entry nozzle may intensify the surface longitudinal cracking sensitivity of the slab. When the lubrication and heat transfer are well regulated between the surface of mold and the mold flux film, low casting speed, large inclination angle and submergence depth of the submerged entry nozzle are beneficial for reducing the possibility of a slab surface longitudinal crack.

关键词： Continuous casting Liquid slag Flow Heat transfer Surface longitudinal cracking sensitivity Mathematical simulation

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Sodium 4-phenylbutyrate Attenuates High-fat Diet-induced Impaired Spermatogenesis

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Biomedical and Environmental Sciences 2018年第12期31卷 876-882页

作者： WANG Er Hui YAO San Qiao TAO Ling XI jin yan Department of Nutrition and Food Hygiene College of Public Health Xinxiang Medical University Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine Xinxiang Medical University

Objective To determine the mitigating effects of sodium 4-phenylbutyrate(4-PBA) on high-fat diet(HFD)-induced spermatogenesis dysfunction. Methods Male rats(n = 30) were randomly divided into three groups: control, HFD, and 4-PBA(HFD +4-PBA). After 13 weeks, rats were euthanized. Testes and epididymis were harvested for further analysis. Sex hormones were detected, and hematoxylin and eosin staining was performed to examine the histological changes in the testes. Semen samples were collected to evaluate sperm quality. Spermatogenic cell apoptosis was detected by TUNEL assay. Results Compared with the control group, the final body weight and body weight gain were significantly higher in HFD-fed rats, while the testicle/body weight ratios were lower(P < 0.05). In HFD-fed rats, obvious pathological changes in the testicular tissue were observed. Treatment with 4-PBA attenuated HFD-induced histological damage, ameliorated the HFD-induced decrease in serum testosterone(T), and reduced the rate of testicular cell apoptosis(P < 0.05) in obese male rats. Finally, 4-PBA significantly improved semen parameters in HFD rats(P < 0.05). Conclusion HFD exposure induced detrimental effects on spermatogenesis, semen quality, serum T level, and testicular cell apoptosis in rats. Treatment with 4-PBA ameliorated HFD-induced impaired spermatogenesis via inhibition of apoptosis in rats. 4-PBA may have therapeutic value in the treatment of obesity-related impairment of spermatogenesis.

关键词： Male infertility Sodium 4-phenylbutyrate Obesity Spermatogenesis Semen Testis

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Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU Li DING Shi-feng WANG Ai-ming CAI jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

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A Novel Self-adaptive Circuit Design Technique Based on Evolvable Hardware

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International Journal of Automation and computing 2020年第5期17卷 744-751页

作者： Jun-Bin Zhang jin-yan Cai Ya-Feng Meng Tian-Zhen Meng Department of Electronic and Optical Engineering Mechanical Engineering CollegeShijiazhuang 050003China

Since traditional fault tolerance methods of electronic systems are based on redundant fault tolerance technique,and their structures are fixed when circuits are designed,the self-adaptive ability is *** order to solve these problems,a novel circuit self-adaptive design technique based on evolvable hardware(EHW)is *** features robustness,self-organization and *** can be adapted to a complex environment through dynamic configuration of the *** this paper,the proposed technique *** consumption of hardware resources and the number of convergence iterations *** effectiveness and superiority of the proposed technique are *** designed circuit has the ability of resistible redundant-state interference(RRSI).The proposed technique has a broad application prospect,and it has great significance.

关键词： Circuit design self-adaptive design redundant fault tolerance technique evolvable hardware(EHW) evolutionary algorithms(EA)

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