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Influence of Joint EMSFN and M-EMS on Fluid Flow in the Mold During Continuous Casting

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1345-1355页

作者： Oleksandr Tretiak Qiang Wang de-wei li Xiao-wei Zhu Chun-Lei Wu Ming He Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern University School of International Exchange Northeastern University School of Resources and Materials Northeastern University at Qinhuangdao School of Metallurgy Northeastern University

Homogenization of physical properties and the chemical composition through the control of liquid metal flow is essentialduring the continuous casting production of billets. This work was aimed at obtaining improved finished products viacontinuous casting that implements two magnetic fields. These fields were realized via two electromagnetic stirringprocesses implemented in a single process： one in the nozzle and one in the mold. The qualitative effects of applyingdouble electromagnetic stirring （EMS） were verified through numerical simulation of 178 mm × 178 mm square billetsexposed to double electromagnetic fields during the continuous casting process. The accuracy of the numerical calculationswas verified via physical experiments. In addition, the final simulation results were compared with the intermediate results,to determine the true effects of different EMS on the metal flow in the mold. The results revealed that casting using EMSwith different directions of magnetic field in the mold and the nozzle has the best effect on the distribution of the fluid flowand minimal influence on the stability of the meniscus and yields the minimum metal-jet penetration into the mold.

关键词： Continuous casting Submerged nozzle Electromagnetic stirring Microstructure

An Improved Robust Model Predictive Control Approach to Systems with linear Fractional Transformation Perturbations

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International Journal of Automation and computing 2011年第1期8卷 134-140页

作者： Peng-Yuan Zheng Yu-Geng Xi de-wei li department of Automation Shanghai Jiao Tong University Shanghai 200240 PRC Key Laboratory of System Control and Information Processing Ministry of Education PRC

In this paper, a robust model predictive control approach is proposed for a class of uncertain systems with time-varying, linear fractional transformation perturbations. By adopting a sequence of feedback control laws instead of a single one, the control performance can be improved and the region of attraction can be enlarged compared with the existing model predictive control （MPC） approaches. Moreover, a synthesis approach of MPC is developed to achieve high performance with lower on-line computational burden. The effectiveness of the proposed approach is verified by simulation examples.

关键词： Robust model predictive control linear fractional transformation (LFT) perturbations linear matrix inequalities (LMIs) feedback model predictive control (MPC) framework sequence of feedback control laws.

Simulation on Effect of Divergent Angle of Submerged Entry Nozzle on Flow and Temperature Fields in Round Billet Mold in Electromagnetic Swirling Continuous Casting Process

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Journal of Iron and Steel Research International 2014年第2期21卷 159-165页

作者： de-wei li Zhi-jian SU Katsukiyo MARUKAWA Ji-cheng HE Key Laboratory of Electromagnetic Processing of Materials of Ministry of Education Northeastern University

A new process for swirling flow generation in the submerged entry nozzle （SEN） in continuous casting process of steel was proposed. A rotating electromagnetic field was set up around the SEN to induce swirling flow by Lorentz force. The flow and temperature fields in the SEN and round billet mold with electromagnetic swirling were numerically simulated and then verified by the electromagnetic swirling model experiment of low melting point alloy. The effects of divergent angle of the SEN on the flow and temperature fields in mold with electromagnetic swirling were investigated. The electromagnetic swirling flow generator （EMSFG） could effectively induce swirling flow of molten steel in the SEN, which consequently improved greatly the flow and temperature fields in the mold. Below the nozzle outlet in mold, with the increase of divergent angle, the stream of bulk flow diverged more widely, the high temperature zone shifted up, and the temperature field became more uniform. Above the nozzle outlet in mold, with 350 A electromagnetic swirling, when the divergent angle of the SEN increased, the upward flow velocity and the meniscus temperature first increased and then decreased. With a divergent angle of 60~, the upward flow velocity and meniscus temperature reaced the largest value.

关键词： continuous casting process swirling flow flow field divergent angle round billet

Severe gastric insufflation and consequent atelectasis caused by gas leakage using AIR-Q laryngeal mask airway:A case report

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World Journal of Clinical Cases 2022年第11期10卷 3541-3546页

作者： Yue Zhao Ping li de-wei li Gao-Feng Zhao Xiang-Yu li department of Anesthesiology The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangdong Provincial Hospital of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina

BACKGROUND The airways of patients undergoing awake craniotomy(AC)are considered“predicted difficult airways”,inclined to be managed with supraglottic airway devices(SADs)to lower the risk of coughing or ***,the special requirements of AC in the head and neck position may deteriorate SADs’seal performance,which increases the risks of ventilation failure,severe gastric insufflation,regurgitation,and *** SUMMARY A 41-year-old man scheduled for AC with the asleep–awake–asleep approach was anesthetized and ventilated with a size 3.5 AIR-Q intubating laryngeal mask airway(LMA).Air leak was noticed with adequate ventilation after head rotation for allowing scalp ***-five minutes later,the LMA was replaced by an endotracheal tube because of a change in the surgical *** surgery,the patient consistently showed low tidal volume and was diagnosed with gastric insufflation and atelectasis using computed *** This case highlights head rotation may cause gas leakage,severe gastric insufflation,and consequent atelectasis during ventilation with an AIR-Q intubating laryngeal airway.

关键词： Insufflation Atelectasis Laryngeal mask airway Craniotomy Case report

Construction and biological activities of human tPA eukaryotic expression plasmid

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Hepatobiliary & Pancreatic Diseases International 2004年第4期3卷 511-515页

作者： Zhong-Jun Wu Su-Fen Yang Shu-Sen Zheng de Shi wei-wei Wu de-wei li Organ Transplant Center First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China. wzjxdfpxy@***

BACKGROUND: Tissue-type plasminogen activator(tPA), which is highly efficient and specific in resolution of thrombus, could significantly improve the survival rate and life-quality of the patients with thrombosis. This study was designed to clone human tPA gene, construct eukaryotic expression plasmid pcDNA3.1(+)/tPA, and evaluate their biological activities.METHODS: The tPA gene was obtained from dead human heart tissue with reverse transcriptase-polymerase chain reaction (RT-PCR). It was cloned to eukaryotic expression plasmid pcDNA3.1(+) by recombination strategy. The eukaryotic expression plasmid pcDNA3.1(+)/tPA was identified by restriction enzyme digestion and sequenced. The pcDNA3.1(+)/tPA was transfected into vascular smooth muscle cell (VSMC) by using lipofection. The tPA expression level was detected by Northern blot and dot blot, and the protein biological activities of tPA were detected by the fibrin plate technique.RESULTS: The tPA gene was cloned and pcDNA3.1(+)/tPA was constructed. The tPA expression levels of mRNA and protein were highly increased after pcDNA3.1(+)/tPA transfected into VSMC, and the expression of tPA protein showed evident biological activities.CONCLUSIONS: The present study has laid a foundation for further animal experiment in treating thrombus in transplanted organ by tPA gene transfection.

关键词： tissue-type plasminogen activator eukaryotic expression plasmid vascular endothelial cell organ transplantation

Overview of Stachybotrys(Memnoniella)and current species status

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Fungal Diversity 2015年第2期71卷 17-83页

作者： Yong Wang Kevin D.Hyde Eric H.C.McKenzie Yu-Lan Jiang de-wei li de-Gang Zhao Guizhou Key Laboratory Agro-Bioengineering Guizhou UniversityGuiyangGuizhou 550025People’s Republic of China department of Plant Pathology College of AgricultureGuizhou UniversityGuiyangGuizhou 550025China Institute of Excellence in Fungal Research School of ScienceMae Fah Luang UniversityChiang RaiThailand Landcare Research Private Bag 92170AucklandNew Zealand Valley Laboratory The Connecticut Agricultural Experiment Station153 Cook Hill RoadWindsorCT 06095USA

Stachybotrys(asexual Hypocreales)has a worldwide *** genus inhabits substrates rich in cellulose and is closely related to *** of species has previously been based on morphology,with conidial characters being considered as *** study reevaluates Stachybotrys and Memnoniella,which is shown to include at least seven species-groups;while Memnoniella is a synonym of *** sexual genera Ornatispora and Melanopsamma are also synonyms of *** the exception of Stachybotrys subsimplex,species formed a wellsupported monophyletic group in LSU data analysis belonging to ***-four accepted Stachybotrys species are discussed,while eight species are considered to belong to other genera or are doubtful in this paper and a key to these species *** new combinations and 1 nomina nova is *** status of Stachybotrys species on health,as human or animal pathogens,in indoor environments,and use as biocontrol agents and compound discovery are also discussed.

关键词： Current species Nomen excludendum Phylogeny Synonyms Taxonomic history

Protective effect of liraglutide on the myocardium of type 2 diabetic rats by inhibiting polyadenosine diphosphate-ribose polymerase-1

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World Journal of Diabetes 2023年第2期14卷 110-119页

作者： Dong-Dong Xue Xiang Zhang de-wei li Yan-Lan Yang Jing-Jin liu department of Endocrinology Shanxi Provincial People's HospitalTaiyuan 030000Shanxi ProvinceChina department of Thyroid Surgery Shanxi Provincial People's HospitalTaiyuan 030000Shanxi ProvinceChina department of Endocrine Shanxi Provincial People's HospitalTaiyuan 030012Shanxi ProvinceChina

BACKGROUND In recent years,studies have found that the occurrence and development of diabetic cardiomyopathy(DCM)is closely related to an increase in polyadenosine diphosphate-ribose polymerase-1(PARP-1)***-1 activation could be involved in the pathophysiological process of DCM by promoting oxidative stress,the inflammatory response,apoptosis and myocardial *** To investigate the mechanism of liraglutide in improving myocardial injury in type 2 diabetic rats,further clarified the protective effect of liraglutide on the heart,and provided a new option for the treatment of *** Forty healthy male SD rats aged 6 wk were randomly divided into two groups,a normal control group(n=10)and a model group(n=30),which were fed an ordinary diet and a high-sugar and high-fat diet,*** successful modeling,the rats in the model group were fed a high-glucose and high-fat diet for 4 wk and randomly divided into a model group and an intervention group(further divided into a high-dose group and a low-dose group).The rats were fed a high-glucose and high-fat diet for 8 wk and then started drug *** samples were collected from the abdominal aorta to detect fasting blood glucose and lipid *** heart tissue was dissected,and its weight was used to calculate the heart weight *** and eosin staining was used to observe the pathological changes in the myocardium and the expression of PARP-1 in the heart by *** The body weight and heart weight index of rats in the model group were significantly increased compared with those in the normal control group,and those in the intervention group were decreased compared with those in the model group,with a more obvious decrease observed in the high-dose group(Pdel group,myocardial fibers were disordered,and inflammatory cells and interstitial fibrosis were *** cardiomyopathy of rats in the intervention group was improved to di

关键词： liraglutide animal models Type 2 diabetic rats Polyadenosine diphosphate-ribose polymerase-1 Haematoxylin and eosin staining Immunohistochemistry

Elevated procalcitonin levels in the absence of infection in procalcitonin-secretin hepatocellular carcinoma:A case report

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World Journal of Clinical Cases 2022年第29期10卷 10811-10816页

作者： Jian-Ting Zeng Yu Wang Yang Wang Zheng-Hua Luo Zhou Qing Yi Zhang Yan-lin Zhang Jie-Feng Zhang de-wei li Xian-Zhang Luo Key Laboratory for Biological Science and Technology of Ministry of Education Chongqing UniversityChongqing University Cancer HospitalChongqing 400044China

BACKGROUND Serum procalcitonin(PCT)is widely used to diagnose bacterial infection and ***,PCT may be elevated in some *** is important to distinguish infection from no infection in such *** relationship between hepatocellular carcinoma(HCC)and PCT is *** SUMMARY A 62-year-old male was admitted due to a hepatic lesion of unknown *** patient had an elevated PCT *** diseases were excluded after appropriate *** then underwent exploratory laparotomy and a left lateral hepatectomy was *** patient recovered with an uneventful postoperative course and PCT level decreased gradually and was normal on day *** was diagnosed by histopathology and no evidence of infection was ***,immunohistochemical analyses revealed that tumor cells were positive for *** HCC cells can secrete PCT in the absence of infection and PCT may be used as a marker to monitor the efficacy of tumor therapy.

关键词： Hepatocellular carcinoma Procalcitonin Infection Case report

Analysis of ultrasonic guided waves propagating in long bones and cortical thickness based on time-frequency methods

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Chinese Journal of Acoustics 2011年第2期30卷 171-180页

作者： LUO Chungou TA de'an li wei WANG weiqi department of Electronic Engineering Fudan University Shanghai 200433

The ultrasonic signals in long bones contain multiple guided modes which are mutual *** velocities of guided waves in long bones are very sensitive to cortical thickness （CTh）.In this paper,Hilbert-Huang transform（HHT） was proposed to analyze multi-mode guided waves,which can decompose superposed waves into many independent *** the group velocity of each mode was obtained at corresponding frequency,which was compared with the results of short time Fourier transform（STFT）.The CTh was also obtained by comparing with the theoretical *** results showed that the experimental determined thickness was in agreement with the actual CTh,indicating that measuring the velocity of the guided mode can be used to estimate the *** HHT is an effective method to identify multimode guided waves.

关键词：超声波信号厚度长骨分析基波传播希尔伯特黄变换 HHT方法时频