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Evolution of Microstructure,Mechanical Properties and Corrosion Resistance of Ultrasonic Assisted Welded-Brazed Mg/Ti Joint

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Journal of Materials Science & Technology 2016年第12期32卷 1253-1259页

作者： Chuan Xu Guangmin sheng Xuezhen Cao Xinjian yuan College of Materials Science and Engineering Chongqing University

Ultrasonic vibration with different powers from 0 k W to 1.6 k W was applied during the tungsten inert gas welding-brazing of Mg/*** microstructures,mechanical properties and corrosion resistance of the ultrasonic assisted tungsten inert gas（U-TIG） welded-brazed Mg/Ti joint were *** results showed that,without being subjected to ultrasonic vibration,coarse columnar α-Mg grains occurred in the fusion zone of Mg/Ti ***,with ultrasonic power of 1.2 k W,the average grain size of columnar α-Mg grains was refined from 200 μm to about 50 μm and the tensile strength of joints increased^18% up to 228 ***,high fraction of grain boundaries was introduced by grain refinement,contributing to improve the corrosion resistance in two ways：（i） accelerating the formation of Mg（OH）2protective layer and（ii） reducing the mismatch and disorder between Mg（OH）2 protective layer and Mg alloy surface.

关键词： Magnesium alloy Titanium alloy Microstructure Mechanical properties Corrosion resistance Ultrasonic vibration

Resilient tightly coupled INS/UWB integration method for indoor UAV navigation under challenging scenarios

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Defence Technology（防务技术） 2023年第4期22卷 185-196页

作者： Qian Meng Yang Song sheng-ying Li yuan Zhuang Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology Southeast UniversityNanjing210096China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHong KongChina State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina

Based on the high positioning accuracy,low cost and low-power consumption,the ultra-wide-band(UWB)is an ideal solution for indoor unmanned aerial vehicle(UAV)localization and ***,the UWB signals are easy to be blocked or reflected by obstacles such as walls and furniture.A resilient tightly-coupled inertial navigation system(INS)/UWB integration is proposed and implemented for indoor UAV navigation in this paper.A factor graph optimization(FGO)method enhanced by resilient stochastic model is established to cope with the indoor challenging *** deal with the impact of UWB non-line-of-sight(NLOS)signals and noise uncertainty,the conventional neural net-works(CNNs)are introduced into the stochastic modelling to improve the resilience and reliability of the *** on the status that the UWB features are limited,a‘two-phase'CNNs structure was designed and implemented:one for signal classification and the other one for measurement noise *** proposed resilient FGO method is tested on flighting UAV platform under actual indoor challenging *** to classical FGO method,the overall positioning errors can be decreased from about 0.60 m to centimeter-level under signal block and reflection *** superiority of resilient FGO which effectively verified in constrained environment is pretty important for positioning accuracy and integrity for indoor navigation task.

关键词： Unmanned aerial vehicle(UAV) Resilient navigation Indoor positioning Factor graph optimization Ultra-wide band(UWB)

General Model of Temperature-dependent Modulus and Yield Strength of Thermoplastic Polymers

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Chinese Journal of Polymer Science 2020年第4期38卷 382-393,I0007页

作者： Ping-yuan Huang Zhan-sheng Guo Jie-Min Feng Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai 200072China

A general model was developed to predict the temperature-dependent modulus and yield strength of different thermoplastic *** model,which depends on only two parameters with clear and specific physical meanings,can describe the temperaturedependent modulus and yield strength of thermoplastic polymers over the full glass transition *** temperature-dependent modulus and yield strength of three thermoplastic polymers were measured by uniaxial tension tests over a temperature range of 243-383 *** predictions showed excellent agreement with the experimental *** analysis of model input parameters showed negligible effect on the present general *** universality of the present general model was further validated,showing excellent agreement with published experimental data on other thermoplastic polymers and their composites.

关键词： Thermoplastics Modulus Yield strength Modeling Glass transition

Hyponatremic encephalopathy due to polyethylene glycol-based bowel preparation for colonoscopy:A case report

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World Journal of Clinical Cases 2023年第1期11卷 187-192页

作者： yuan Zhao Hai-sheng Dong Department of Critical Care Medicine Shanghai TCM-integrated HospitalShanghai 200082China

BACKGROUND Adequate bowel preparation is critical for colonoscopy *** present,the most widely used intestinal cleaner recommended at home and abroad is Polyethylene glycol(PEG).Intestinal cleansers can cause electrolyte disturbances and ***,hyponatremic encephalopathy due to hyponatremia induced by PEG solution,although rare,can lead to serious irreversible sequelae and even *** SUMMARY In this report,we discuss a case of neurological dysfunction due to hyponatremia,also known as hyponatremic encephalopathy,observed in a 63-year-old woman who underwent PEG-based bowel preparation for *** was eventually transferred to our intensive care unit for treatment due to her Glasgow Coma Scale score of 9/15(Eye opening 2;Verbal response 1;Motor response 6)and abnormal laboratory *** Physicians should be thoroughly familiarized with the patient’s history before prescribing PEG for bowel preparation,and timely identification of patients with hyponatremic encephalopathy is essential as delayed treatment is associated with poor neurological *** intravenous infusion of 3%sodium chloride is recommended at the onset of early *** goal of treatment is to adequately treat cerebral edema while avoiding serum sodium correction beyond 15 to 20 m Eq/L within 48 h of treatment to prevent osmotic demyelination syndrome.

关键词： Polyethylene glycol Intestinal preparation Hyponatremic encephalopathy Hyponatremia Brain Case report

Effect of Oxygen on Surface Properties and Drug Release Behavior of Plasma Polymer of n-Butyl Methacrylate

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Chinese Chemical Letters 2005年第12期16卷 1641-1644页

作者： yuan yuan Chang sheng LIU yuan ZHANG Min YIN Jie XU Engineering Research Center for Biomedical Materials of Ministry of Education ECUST Center of Analysis and Research ECUST Shanghai 200237

The effects of oxygen on the chemical structure, morphology, hydrophilicity and drug release behavior of radio-frequency plasma poly n- butyl methacrylate （PPBMA） thin film were carded out for the first time. ATR-FTIR and XPS showed that oxygen had little influence on the chemical structure and composition of PPBMAs, which did not agree with the thought that the presence of oxygen gas would increase the oxidized carbon functionalities in the plasma polymer. SEM and static contact angle measurement indicated that in case of deposition with oxygen, the smoothness and hydrophilicity of PPBMA were dramatically improved. The drug release behavior showed that drug release from the PPBMA coating without oxygen was biphasic patterns, while from PPBMA coating with oxygen was Higuchi release. These results were helpful for the design and tailoring of the PPBMA polymer film and other of plasma polymers film, but could provide a new idea for the drug release controlled form.

关键词： Plasma n-butyl methacrylate polymer oxygen chemical structure morphology hydrophilicity

Constructions of vector output Boolean functions with high generalized nonlinearity

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 77-81页

作者： KE Pin-hui ZHANG sheng-yuan Key Laboratory of Network Security and Cryptology Fujian Normal UniversityFujian 350007 China

Carlet et al. recently introduced generalized nonlinearity to measure the ability to resist the improved correlation attack of a vector output Boolean function. This article presents a construction of vector output Boolean fimctions with high generalized nonlinearity using the e-biased sample space. The relation between the resilient order and generalized nonlinearity is also discussed.

关键词： Boolean functions correlation attack generalizednonlinearity almost resilient functions

Protective effect of recombinant human IL-1Ra on CCl_4-induced acute liver injury in mice

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World Journal of Gastroenterology 2010年第22期16卷 2771-2779页

作者： Zhu, run-Zhi Xiang, Di Xie, Chao Li, Jing-Jing Hu, Jian-Jun He, Hong-Lin yuan, Yun-sheng Gao, Jin Han, Wei Yu, Yan Shanghai Jiao Tong Univ Sch Agr & Biol Shanghai Municipal Key Lab Vet Biotechnol Shanghai 200240 Peoples R China Shanghai Jiao Tong Univ Lab Regenerat Sch Pharm Shanghai 200240 Peoples R China Cornell Univ Dept Food Sci Ithaca NY 14853 USA Shanghai Jiao Tong Univ Coll Med Shanghai Peoples Hosp 6 Dept Infect Dis Shanghai 200233 Peoples R China

AIM: To evaluate the effects of positive regulation of recombinant human interleukin 1 receptor antagonist (rhIL-1Ra) on hepatic tissue recovery in acute liver injury in mice induced by carbon tetrachloride (CCl 4 ). METHODS: Acute liver damage was induced by injecting 8-wk-old mice with CCl 4 1 mL/kg (1:3 dilution in corn oil) intraperitoneally (ip). Survival after liver failure was assessed by injecting 8-wk-old mice with a lethal dose of CCl 4 2.6 mL/kg (1:1 dilution in corn oil) ip. Mice were subcutaneously injected with 1 mg/kg recombinant human IL-1Ra twice a day after CCl 4 treatment for 5 d. Serum alanine amino transferase (ALT) and aspartate aminotransferase (AST) levels were determined with a commercial assay kit. Serum IL-1β, IL-1Ra levels were measured by enzyme-linked immunosorbent assay kit. Quantitative real-time polymerase chain reaction was used to determine liver IL-1β, IL-1Ra and IL-6 expression during CCl 4-induced acute liver injury. Liver sections were stained with hematoxylin-eosin. A histology-injury grading system was used to evaluate the degree of necrosis after acute liver injury. Proliferating cell nuclear antigen (PCNA) staining was used to evaluate the role of rhIL-1Ra in promoting hepatocyte proliferation. RESULTS: Quantitative analysis showed a higher level of IL-6 mRNA expression and reduced serum AST and ALT levels in the livers of the rhIL-1Ra-treated group at the early phase of CCl 4-induced acute liver injury. Histological examination indicated a decrease in centrilobular necrotic areas in mice treated with rhIL-1Ra, and a novel role of rhIL-1Ra in promoting hepatocyte proliferation was also supported by an increase of PCNA staining. All these results, accompanied by a strong survival benefit in rhIL-1Ra-treated vs PBS-treated groups, demonstrated that rhIL-1Ra administration ameliorated the histological damage and accelerated the regeneration and recovery process of the liver. CONCLUSION: rhIL-1Ra could be further developed as a

关键词： Recombinant human interleukin 1 receptor antagonist Carbon tetrachloride Liver injury Hepatocyte proliferation

Study of the thermal influence on the dynamic characteristics of the motorized spindle system

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Advances in Manufacturing 2016年第4期4卷 355-362页

作者： Song-sheng Li yuan Shen Qiang He School of Mechatronic Engineering and Automation Shanghai Key Laboratory of Intelligent Manufacturing andRobotics Shanghai University Shanghai 200072People's Republic of China School of Mechanical Engineering Anyang Institute ofTechnology Anyang 455000 HenanPeople's Republic of China

The severe internal heat generation of the motorized spindle system causes uneven temperature dis- tribution, and will affect the vibration characteristics of the system. Based on the thermal analysis about the motorized spindle by finite element method （FEM）, the thermal deformations of the spindle system are calculated by the thermal structure coupling simulation, and the thermal deformations of the rotor and the bearing units are extracted to analyze the bearing stiffness changes so that the modal characteristics of the rotor can be simulated in different thermal state conditions. And then the rotor thermal deformation experiment and the modal experiment of spindle by exciting with hammer are performed. The result shows that the thermal state of the motorized spindle system has a significant influence on the natural frequency of the rotor, which can be carefully treated when a spindle system is designed.

关键词： Motorized spindle Thermal characteristic Thermal-structure coupling Modal analysis Spindlesystem

One-sided empirical Bayes test for location parameter in Gamma distribution

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Applied Mathematics(A Journal of Chinese Universities) 2018年第3期33卷 287-297页

作者： yuan Min ZHANG Qian WEI Lai-sheng School of Public Health Administration Anhui Medical University Department of Statistics and Finance University of Science and Technology of China

In this paper, we devote to constructing the one-sided empirical Bayes(EB) test for the location parameter in the Gamma distribution by nonparametric method. Under some mild conditions, we prove that the EB test is asymptotically optimal with the rate of the order O(n^(-δs/(2s+1))), where 1/2 ≤ δ 1 is a given natural number. An example is also given to illustrate that the conditions of the main theorems are easily satisfied.

关键词： three parameter Gamma distribution location parameter one-sided empirical Bayes test asymptotically optimality convergence rate