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Laser powder bed fusion of NiTiFe shape memory alloy via premixed powder:microstructural evolution,mechanical and functional properties

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Rare Metals 2024年第5期43卷 2300-2316页

作者： Bo Yuan Jin-Guo Ge Liang Zhang hong-jun chen Long-Sha Wei Yu-Duo Zhou Run-Hua Song Institute of Intelligent Manufacturing Technology Shenzhen PolytechnicShenzhen 518055China School of Mechanical and Electrical Engineering Guilin University of Electronic TechnologyGuilin 541004China Guangdong Advanced Polymer Composite Engineering Technology Research Center Shenzhen Academy of Aerospace TechnologyShenzhen 518057China Jihua Laboratory Testing Center Jihua LaboratoryFoshan 528000China

High-cost pre-alloyed powder is the bottleneck problem that limits the widespread application of additivemanufactured shape memory *** this work,the lowcost ternary NiTiFe shape memory alloy is fabricated by laser powder bed fusion(LPBF)technique via mechanically mixed pre-alloy NiTi powder and varying contents pure Fe powder(1,2,3 wt%).All NiTiFe alloys show a relative density of up to 99.8%by optimizing the LPBF processing *** to the heterogeneous nucleation effect of micron-sized Fe particles,both grain refinement and texture weakening are generated in the NiTiFe alloys,accompanied by the reduction of dislocation *** the room-temperature mechanical properties,the NiTi-3Fe alloy shows the highest microhardness of HV370,but the fracture strength and elongation reduce to1701 MPa and 23%*** evolution of mechanical properties is attributed to the high internal defects,low dislocation density and the incoherent ***,the NiTi-3Fe alloy shows the quasi-linear superelasticity behavior;the superelastic recoverable strain of NiTi-1Fe and NiTi-2Fe decreased with the increase in Fe *** study provided a new-fangled insight for the development of multi-component NiTi-based shape memory alloys by additive manufacturing.

关键词： Additive manufacturing Shape memory alloy Metal matrix composite Microstructure Mechanical properties

Supercapacitor electrode based on few-layer h-BNNSs/rGO composite for wide-temperature-range operation with robust stable cycling performance

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International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 220-231页

作者： Tao Yang Hui-juan Liu Fan Bai En-hui Wang jun-hong chen Kuo-Chih Chou Xin-mei Hou Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Currently,developing supercapacitors with robust cycle stability and suitability for wide-temperature-range operations is still a huge *** the present work,few-layer hexagonal boron nitride nanosheets(h-BNNSs)with a thickness of 2−4 atomic layers were fabricated via vacuum freeze-drying and ***,the h-BNNSs/reduced graphene oxide(rGO)composite were further prepared using a hydrothermal *** to the combination of two two-dimensional(2D)van der Waals-bonded materials,the as-prepared h-BNNSs/rGO electrode exhibited robustness to wide-temperature-range operations from−10 to 50℃.When the electrodes worked in a neutral aqueous electrolyte(1 M Na2SO4),they showed a great stable cycling performance with almost 107%reservation of the initial capacitance at 0℃ and 111% at 50℃ for 5000 charge−discharge cycles.

关键词： few-layer hexagonal boron nitride wide-temperature-range operation cycling performance

Analysis of principle deviation of subpixel Zernike moments operator

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Optoelectronics Letters 2007年第5期3卷 376-380页

作者： QU Ying-dong LI Rong-de YUAN Xiao-guang HUANG hong-jun LI chen-xi School of Material and Engineering Shenyang University of Technology Shenyang 110023 China

In original Zernike moments subpixel edge operator, ideal step edge model is chosen for calculating four parameters of a pixel point, and therefore principle deviation is caused by edge model. In order to discuss the effect of principle deviation on edge location, sampled edge model is chosen for calculating edge parameters, principle deviation of edge translation l is derived based on Zernike moments edge detection theory, and modified formula of l is given for Zernike moments operator with masks of 5×5 size. Both theory analysis and testing result demonstrate that principle deviation is zero when edge translation l is limited in central pixel of a sampled window. In another case, the modification of l should be considered, which results in edge location accuracy of non-subpixel level for this subpixel edge operator.

关键词：图象处理偏差边缘算子边界模型

Effect of Hyperbaric Oxygen on the Growth of Intracranial Glioma in Rats

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Chinese Medical Journal 2015年第23期128卷 3197-3203页

作者： Jian-Bo Ding jun-Rui chen hong-Zhi Xu Zhi-Yong Qin Department of Neurosurgery Huashan Hospital Shanghai Medical College Fudan University Shanghai 200040 China

Background： Numerous studies have confirmed that hyperbaric oxygen （HBO） in combination with radiotherapy or chemotherapy may increase the efficacy of radiotherapy or chemotherapy in patients with glioma. However, whether HBO therapy alone may inhibit or promote the growth of malignant tumors remains controversial. This study aimed to investigate the effect of HBO on the growth of glioma in rats, and the impact of HBO on the expression of vascular endothelial growth factor （VEGF） and hypoxia-inducible factor 1-alpha （HIF-1α）, angiogenesis, and apoptosis of glioma cells. Methods： Male Sprague-Dawley rats were treated with or without HBO after glioma cell inoculation and followed for up to 16 days postinoculation. Rats were randomized to receive bilateral forelimb function tests （n = 20 per group） and head magnetic resonance imaging （n = 5 per group）. Differences between HBO and control groups were tested using 2-sample independent t-tests and changes over time within treatment groups were analyzed using a repeated measurement analysis of variance with Bonferroni correction. The effect of H BO on the expression of VEGF, HIF-1α, yon Willebrand factor, angiogenesis, and tumor cell apoptosis were also examined （n = 5 per group）. Results： Forelimb function scores were reduced in both HBO-treated and control groups. HBO-treated rats had significantly larger tumor volume and more water in the cerebellum compared with control rats. The intratumoral expression of VEGF was significantly higher in HBO-treated rats compared with control rats （23.2% vs. 13.3%, P = 0.002）. HIF-1α was significantly increased in HBO-treated rats compared with controls in the expression of both intratumoral （72.7% vs. 54.9%, P= 0.001） and peritumoral （2.6% vs. 1.9%, P = 0.003） cells. The intratumoral microvessel density （MVD） was significantly higher in the HBO group （15.6 vessels/field vs. 4.4 vessels/field. P 〈 0.001 ）, and the peritumoral MVD was not significantly different between the two groups

关键词： Angiogenesis Apoptosis Glioma Hyperbaric Oxygen Rat

Prognosis of 153 patients with decompensated hepatitis B virus-related cirrhosis is improved after 3-year continuous lamivudine treatment

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Chinese Medical Journal 2013年第8期126卷 1538-1543页

作者： chen Guang-cheng YU Tao MIN Xiao-hui ZHAO Li-na QING Qing YUAN Yu-hong SU hong ZHAN jun HUANG Kai-hong chen Qi-kui Department of Gastroenterology Sun Yat-sen Memorial HospitalSun Yat-sen University Guangzhou Guangdong 510120 China

Background The long-term effectiveness and safety of lamivudine in patients with decompensated hepatitis B virus-related cirrhosis are still not clear. The present study attempted to describe the clinical outcomes of lamivudine therapy in these special patients over three years. Methods This study was a retrospective, controlled cohort study which involved 153 patients with decompensated hepatitis B virus-related cJrrhosJs. Of these, 86 patients received lamJvudJne 100 mg daily accompanied with general internal treatment, and the other 67 were given general internal treatment only. Significant clinical responses were recorded after years of antiviral treatment. Results The patients in both groups were matched in terms of age, sex and laboratory results at baseline. After years of therapy, the Child-Pugh-Turcotte scores and laboratory values of the patients receiving lamivudine were remarkably improved compared to the patients in the control group. The mortality rate and the incidence of cirrhosis-related complications were much lower in the lamivudine group than in the control group. Genotypic resistance tyrosine, methionine, aspartate, aspartate mutations developed in 26.7 percent of the patients during 3-year lamivudine treatment, and cirrhosis-related death and the hepatocellular carcinoma were more likely to occur in patients with these mutations than in the other patients who were treated with lamivudine. Conclusions Continuous long-term lamivudine treatment in patients with decompensated hepatitis B virus-related cirrhosis delays clinical progression, and significantly improves hepatic function and prognosis. However, the use of a retrospective control cohort precludes drawin（~ definitive conclusions.

关键词： lamivudine decompensated hepatitis B virus-related cirrhosis, retrospective cohort study

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补燃循环发动机关机过程仿真研究

推进技术 2016年第12期37卷 2219-2225页

作者：陈宏玉刘红军陈建华洪流液体火箭发动机技术国防科技重点实验室陕西西安710100

以补燃循环液氧煤油发动机系统为研究对象,对其关机特性进行了研究。在分析发动机系统工作原理的基础上,应用模块化建模的思想,建立了该系统中各主要部件的数学模型;采用新的面向对象仿真语言Modelica和MWorks平台,开发了可扩展的发动... 详细信息

以补燃循环液氧煤油发动机系统为研究对象,对其关机特性进行了研究。在分析发动机系统工作原理的基础上,应用模块化建模的思想,建立了该系统中各主要部件的数学模型;采用新的面向对象仿真语言Modelica和MWorks平台,开发了可扩展的发动机仿真模型库;在此基础上,利用模型库搭建了液氧煤油补燃循环发动机关机过程仿真模型,并对发动机关机过程进行了仿真计算,计算结果表明与试车数据基本相符,其中稳态相对误差小于5%,动态相对误差小于15%,初步验证了所建仿真模型的正确性;进一步分析了吹除气体压力、阀后腔道容积、关机工况等因素对发动机关机过程的影响。

关键词：液体火箭发动机补燃循环关机过程数值仿真

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu chen Xue-jun Li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Fetal reduction by bipolar cord coagulation in managing complicated monochorionic multiple pregnancies： preliminary experience in China

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Chinese Medical Journal 2010年第5期123卷 549-554页

作者： HE Zhi-ming FANG Qun YANG Yong-zhong LUO Yan-min chen jun-hong chen Yong-zhen ZHOU Yi chen Min-ling Fetal Medicine Center First Affiliated Hospital of Sun Yat-sen University Guangzhou Guangdong 510080 China

Background Monochorionic multiple pregnancies （MMPs） are associated with higher rates of perinatal morbidity and mortality caused by interfetal vascular anastomoses in the monochorionic placenta, which can lead to fetal health interactions. In some circumstances, selective feticide of the affected fetus is necessary to save the healthy co-twin. We evaluated the effects and safety of our initial experiences using bipolar cord coagulation for the management of complicated MMPs. Methods Using ultrasound-guided bipolar cord coagulation, we performed selective feticide on 14 complicated MMPs （5 with twin-twin transfusion syndrome, 4 with acardia, 3 with discordant structural anomalies, and 2 with severe selective intrauterine growth restriction）. One patient with monochorionic triplets received the procedure twice to terminate 2 affected fetuses for different JndJcatJons. Data regarding the operations, complications and neonatal outcomes were analyzed. Results Cord occlusions were successfully performed in 13/14 （93%） cases. The failure happened in an acardiac fetus and the pregnancy was terminated by induction. The included cases delivered at a mean gestational age of 35.4 weeks with a perinatal survival rate of 11/13 （85%）. Three operation-related complications occurred （21%）, including membrane rupture of the terminated sac （1 case）, preterm labor at 28 weeks gestation （1 case）, and chorioamniotic membrane separation （1 case）. Amnioinfusion was indicated in 11 procedures to expand the target sacs for entering the trocar and obtaining sufficient working space. However, in all 4 cases of acardia, the acardiac sacs showed extreme oligohydramnios and could not be well expanded by infusion; thus, the trocar had to be inserted from the sac of the preserved co-twin. Conclusions The application of bipolar cord coagulation in complicated MMPs is safe and improves the prognosis. Amnioinfusion is useful in helping to expand the target sac when the working space is limited.

关键词： pregnancy reduction, multifetal," monochorionic cord coagulation," twin-twin transfusion syndrome," acardia

Spectroelectrochemical Studies on the Interactions of Complexes of Cu(phen)^(2+)_(2) and Cu(bpy)^(2+)_(2) with DNA

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Chemical Research in Chinese Universities 1997年第2期13卷 25-33页

作者： ZHAO Guang chao, ZHU jun jie and chen hong yuan ** (Department of Chemistry, the State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing, 210093)

The interactions of the complexes of Cu(phen) 2+ 2 and Cu(bpy) 2+ 2 with DNA were investigated with electrochemistry and spectroelectrochemistry. Binding constants( K n + ) and the reaction model were obtained from their electrochemical behavior and electrochemical data. The binding constants( K 2+ ) for Cu(phen) 2+ 2 DNA and Cu(bpy) 2+ 2 DNA were 8 51×10 3 L·mol -1 and 3 27×10 3 L·mol -1 , and K +s were 3 09×10 4 L·mol -1 and 5 66×10 3 L·mol -1 respectively. The spectroscopic characteristics of the complexes of Cu(phen) 2+ 2 DNA and Cu(bpy) 2+ 2 DNA were studied in detail. Some significant spectroelectrochemical data were obtained. The interaction of DNA with complexes was described.

关键词： DNA Interaction Cu(phen) 2+ 2 Cu(bpy) 2+ 2 Spectroelectrochemistry