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Grain-refining and strengthening mechanisms of bulk ultrafine grained CP-Ti processed by L-ECAP and MDF

Journal of Materials Science & Technology 2021年第24期83卷 196-207页

作者： Peng-Cheng Zhao Guang-Jian Yuan Run-Zi Wang Bo Guan Yun-Fei Jia xian-Cheng Zhang Shan-tung tu Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai200237China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing400044China

The microstructural evolution and mechanical properties of ultrafine-grained(UFG)CP-Ti after an innovative large-volume equal channel angular pressing(L-ECAP)and multi-directional forging(MDF)were systematically examined using monotonic tensile tests combined with transmission electron microscope(TEM)and electron backscatter diffraction(EBSD)*** refined and homogeneous microstructures were achieved after L-ECAP(8-pass and 12-pass)and MDF(2-cycle and 3-cycle),respectively,where the grain size distribution conformed to lognormal *** grain refinement of450℃L-ECAP is dominated by dynamic recrystallization(DRX)and dynamic recovery(DRV),while that of MDF is dominated by *** iron impurities promote recrystallization by pinning-induced dislocation accumulation so that DRX is prone to occur at iron segregation regions during *** monotonic tensile results show that the strain hardening rate of CP-Ti increases with the decrease of grain size,while the continuous strain hardening ability *** relationship between the average grain size and yield strength is in accordance with Hall-Petch ***,the individual strengthening mechanisms were quantitatively examined by the modified *** results indicate that the strengthening contribution of dislocation accumulation to yield strength is greater than that of grain refinement.

关键词： Equal channel angular pressing Multi-directional forging Ultrafine grain Recrystallization Strain hardening Hall-Petch relation

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The higher grain production, the more social deprivation? A case study of henan province in traditional agricultural areas of China

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Journal of Mountain Science 2018年第1期15卷 167-180页

作者： GAO Jun-bo QIAO Wei-feng LIU Yan-sui LI Yu-rui tu Wei ZHANG Yong-xian Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences School of Geography Science Xinyang Normal University School of Geography Science Nanjing Normal University Department of Geology & Geography Georgia Southern University Institute of Surveying And Mapping Information Engineering University

This paper examines the spatial-temporal dynamics of inequality from the perspective of social deprivation in the context of continuous growth of grain production using national census data from 2000 and 2010 for henan province,*** analytical results show an overall level of social deprivation that is high and a widening social deprivation gap at the county *** social deprivation shows great spatiotemporal heterogeneity,the higher deprived counties are mainly distributed in central and eastern henan province,while counties with lower social deprivation are clustered in northwestern regions,formed a belt-shape spatial differential between the south(higher deprived counties clustered)and northwest(low deprived counties clustered)henan in 2000,and changed toward a core-periphery semi annular spatial structure in 2010,the low deprived counties surrounded by high deprived *** social deprivation shows a"west low and east high"spatial pattern,similar to the grain production in henan *** development level was low in most counties in Yudong plain despite of keeping the continuous increase of grain production,meaning the higher grain output did not result in the more social development expected in Chinese traditional agricultural areas,and the regional disparity is expected to increase in the near future if development conditions are not changed,which could inspire more targeted rural governance options.

关键词： Spatial-temporal change Grain production Social inequality Social deprivation henan province

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Polyethylene glycol as a promising synthetic material for repair of spinal cord injury

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Neural Regeneration Research 2017年第6期12卷 1003-1008页

作者： xian-bin Kong Qiu-yan Tang Xu-yi Chen Yue tu Shi-zhong Sun Zhong-lei Sun Department of Brain Affiliated Hospital of China Logistics College of People's Armed Police Forces Tianjin University of Traditional Chinese Medicine Tianjin Key Laboratory of Neurological Trauma Repair Jinzhou Medical University

Polyethylene glycol is a synthetic, biodegradable, and water-soluble polyether. Owing to its good biological and material properties, polyethylene glycol shows promise in spinal cord tissue engineering applications. Although studies have examined repairing spinal cord injury with polyethylene glycol, these compelling findings have not been recently reviewed or evaluated as a whole. Thus, we herein review and summarize the findings of studies conducted both within and beyond China that have examined the repair of spinal cord injury using polyethylene glycol. The following summarizes the results of studies using polyethylene glycol alone as well as coupled with polymers or hydrogels：（1） polyethylene glycol as an adjustable biomolecule carrier resists nerve fiber degeneration, reduces the inflammatory response, inhibits vacuole and scar formation, and protects nerve membranes in the acute stage of spinal cord injury.（2） Polyethylene glycol-coupled polymers not only promote angiogenesis but also carry drugs or bioactive molecules to the injury site. Because such polymers cross both the blood-spinal cord and blood-brain barriers, they have been widely used as drug carriers.（3） Polyethylene glycol hydrogels have been used as supporting substrates for the growth of stem cells after injury, inducing cell migration, proliferation, and differentiation. Simultaneously, polyethylene glycol hydrogels isolate or reduce local glial scar invasion, promote and guide axonal regeneration, cross the transplanted area, and re-establish synaptic connections with target tissue, thereby promoting spinal cord repair. On the basis of the reviewed studies, we conclude that polyethylene glycol is a promising synthetic material for use in the repair of spinal cord injury.

关键词： glycol repair polyethylene degeneration hydrogel scaffold synaptic alone biodegradable inducing

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柱输运管中扩散超声速辐射波的能流

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物理学报 2006年第7期55卷 3789-3795页

作者：蓝可贺贤土赖东显李双贵北京应用物理与计算数学研究所北京100088

采用于敏关于直角坐标系下两平板间粒子传输的辐射能流计算的理论模型,给出了柱输运管中与径向位置相关的谱辐射能流的计算公式.研究结果表明,由于管壁的自由程远小于传输介质的自由程,从而导致辐射能流中几何因子随径向变化,并认为这... 详细信息

采用于敏关于直角坐标系下两平板间粒子传输的辐射能流计算的理论模型,给出了柱输运管中与径向位置相关的谱辐射能流的计算公式.研究结果表明,由于管壁的自由程远小于传输介质的自由程,从而导致辐射能流中几何因子随径向变化,并认为这是最近关于扩散超声速辐射波实验中测得的辐射波强度随径向呈拱形分布的又一个重要原因.另外,还给出对横截面平均的谱辐射能流、以及当辐射与物质处于局部热动平衡时的辐射能流的计算公式,并将其中的几何因子与人们传统的通过几何自由程获得的几何因子进行了比较.为方便数值模拟,还给出了辐射能流公式中含有多重复杂积分的几何因子的拟合表达式.

关键词：柱管中扩散超声速辐射波传输辐射能流几何因子

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Schisandrin B Protects against Ischemic Brain Damage by Regulating PI3K/AKT Signaling in Rats

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中国结合医学杂志:英文版 2023年第10期29卷 885-894页

作者： HONG Quan-long DING Yi-hang CheN Jing-yi SHI Song-sheng LIANG Ri-sheng tu xian-kun Department of Neurology The First Hospital of Quanzhou Affiliated to Fujian Medical UniversityQuanzhouFujian Province362000China Department of Neurosurgery Fujian Medical University Union HospitalFuzhou350001China

Objective To explore the effect and mechanism of schisandrin B(Sch B)in the treatment of cerebral ischemia in *** The cerebral ischemia models were induced by middle cerebral artery occlusion(MCAO)and ***-Dawley rats were divided into 6 groups using a random number table,including sham,MCAO,MCAO+Sch B(50 mg/kg),MCAO+Sch B(100 mg/kg),MCAO+Sch B(100 mg/kg)+LY294002,and MCAO+Sch B(100 mg/kg)+wortmannin *** effects of Sch B on pathological indicators,including neurological deficit scores,cerebral infarct volume,and brain edema,were subsequently *** apoptosis was identified by terminal transferase-mediated dUTP nick end-labeling(tuNEL)*** protein expressions involved in apoptosis,inflammation response and oxidative stress were examined by immunofluorescent staining,biochemical analysis and Western blot analysis,*** effect of Sch B on phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)signaling was also *** Sch B treatment decreased neurological deficit scores,cerebral water content,and infarct volume in MCAO rats(PtuNEL staining indicated that Sch B also reduced apoptosis in brain tissues,as well as the Bax/Bcl-2 ratio and caspase-3 expression(Phe production of myeloperoxidase,malondialdehyde,nitric oxide and superoxide dismutase,as well as the release of cytokine interleukin(IL)-1βand IL-18,in MCAO rats(Phe phosphorylation of PI3K and *** the PI3K/AKT signaling pathway with LY294002 or wortmannin reduced the protective effect of Sch B against cerebral ischemia(Phe PI3K/AKT *** B had a potential for treating cerebral ischemia.

关键词： cerebral ischemia inflammation neuroprotection PI3K/AKT signaling schisandrin B Chinese medicine

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Lamellar aspect-ratio and thickness-dependent strength-ductility synergy in pure nickel during in-situ micro-tensile loading

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Journal of Materials Science & Technology 2023年第26期157卷 89-97页

作者： Zi-Meng Wang Yun-Fei Jia Kai-Shang Li Yong Zhang Jia-Dong Cai xian-Cheng Zhang Hiroyuki Hirakata Shan-tung tu Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China Department of Mechanical Engineering and Science Kyoto UniversityKyoto daigaku-katsuraNishikyo-kuKyoto 615-8540Japan

In order to overcome the trade-offbetween strength and ductility in traditional metallic materials,the gradient lamellar structure was fabricated through an ultrasound-aided deep rolling technique in pure Ni with high stacking fault energy after heat *** gradient lamellar Ni was successively di-vided into three ***-situ micro-tensile tests were performed in different regions to reveal the corresponding microscopic mechanical *** characterization techniques were adopted to explore the effects of microstructural parameters and defects on mechanical *** work demonstrates that the micro-tensile sample with small lamellar thickness and large aspect ratio possesses excellent strength and ductility when the loading direction is parallel to the long side of lamellar grain *** finding is helpful to the design of metallic material microstructure with superior com-prehensive *** one hand,the reason for high strength is that the strength increases with the decrease of lamellar thickness according to the Hall-Petch ***,initial dislocation density also participates in the strengthening *** the other hand,the deformation mechanisms include dislocation slip,grain rotation,and the effects of grain boundaries on dislocations,jointly contributing to good ductility.

关键词： Lamella In-situ micro-tensile test Strength-ductility synergy Aspect ratio Grain rotation

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Investigation on the structural feature of Shengli lignite

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International Journal of Mining Science and Technology 2018年第2期28卷 335-342页

作者： Zhang Yang-Yang Zong Zhi-Min Sun Yi-Bing Liu Fang-Jing Li Wei-tu Wang Ya-Nan Wei xian-Yong Key Laboratory of Coal Processing & Efficient Utilization Ministry of Education China University of Mining & Technology

The extraction residue from Shengli lignite was sequentially dissolved in cyclohexane, benzene, methanol, ethanol, and isopropanol in an autoclave at 320℃ to afford soluble portions(SPs) 1–5(SP_1-SP_5) and the final residue(FR). The total yield of SP_1-SP_5 is ca. 55.1%. The FR was subjected to ruthenium ioncatalyzed oxidation and the resulting products were isolated from the reaction mixture and *** the esterified products and SP_1-SP_5 were analyzed with a gas chromatograph/mass *** total, 342 compounds were identified in SP_1-SP_5. They can be classified into normal alkanes, branched alkanes, alkenes, alkanedienes, arenes, alkanols, methylcycloalkanes, alkenols, alkylbenzenemethanols,arenols, anisol and substituted anisols, polymethyldihydrobenzofurans, arenofurans, dibenzofurans,ethoxymethylbenzenes, aldehydes, ketones, esters, nitrogen-containing organic compounds, sulfurcontaining organic compounds, and other compounds. Among the compounds, arenols are predominant in SP_1 and SP_2 and the main compounds in SP_3, while the main compounds in SP_4 and SP_5 are esters and arenes, respectively. According to the esterified products identified, the products from the FR oxidation can be grouped into non-benzene ring carboxylic acids(NBCAs) and benzenepolycarboxylic acids(BPCAs). The total yield of BPCAs is much higher than that of NBCAs, suggesting that the FR is rich in condensed aromatic moieties.

关键词： Lignite Arenols Esters Arenes Condensed aromatic moieties

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GBW08771乙腈中噻虫嗪溶液标准物质的研制

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食品安全质量检测学报 2024年第14期15卷 155-160页

作者：李先江涂梦灵王建东吕辅菊中国计量科学研究院化学计量与分析科学研究所北京100029 北京科技大学化学与生物工程学院北京100083

目的研制乙腈中噻虫嗪的溶液有证标准物质GBW08771,满足国内外机构对于噻虫嗪农药残留检测的需求。方法该溶液标准物质以准确定值的噻虫嗪纯品为原料,以色谱纯乙腈为溶剂,采用重量容量法在容量瓶中准确配制,制备值为10.0μg/m L。以液... 详细信息

目的研制乙腈中噻虫嗪的溶液有证标准物质GBW08771,满足国内外机构对于噻虫嗪农药残留检测的需求。方法该溶液标准物质以准确定值的噻虫嗪纯品为原料,以色谱纯乙腈为溶剂,采用重量容量法在容量瓶中准确配制,制备值为10.0μg/m L。以液相色谱外标法进行定量,检测波长为254nm。结果依据JJF1343—2022《标准物质的定值及均匀性、稳定性评估》的要求,本标准物质的均匀性良好、短期稳定性(50℃,14 d)和长期稳定性(20℃,24个月)达到国家一级标准物质规范的要求。该标准物质的不确定度来自噻虫嗪原料纯度(0.18%)、溶液配制(0.39%)、均匀性(0.06%)、短期稳定性(0.21%)和长期稳定性(0.12%)5个方面。结论噻虫嗪溶液标准物质GBW08771的量值为10.0μg/mL,扩展不确定度为1%(k=2),该标准物质对于保障农产品、食品安全以及实验室质量控制等具有重要意义。

关键词：噻虫嗪标准物质不确定度

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融入OBE理念的专业基础课程教学改革与实践——基于“材料成型工艺基础”课程的探索

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南昌航空大学学报（自然科学版） 2024年第2期38卷 120-125页

作者：董显娟徐勇魏科李鑫姜丽红涂泽立南昌航空大学航空制造工程学院南昌330063 南昌航空大学通航学院南昌330063

本课程教学改革立足新工科建设,以工程教育为导向,结合学校“航空特色鲜明,工科优势突出”的办学定位,坚持以学生为中心,利用现代信息技术手段,基于OBE理念采用启发式、任务驱动式、问题探究式等多种教学方法,旨在提高课程目标达成度。... 详细信息

本课程教学改革立足新工科建设,以工程教育为导向,结合学校“航空特色鲜明,工科优势突出”的办学定位,坚持以学生为中心,利用现代信息技术手段,基于OBE理念采用启发式、任务驱动式、问题探究式等多种教学方法,旨在提高课程目标达成度。通过对近3年材料成型与控制工程专业本科生成绩分析,着眼于解决目前课程体系同质化、教学方法单一化、课程质量不高的问题,促进形成“夯实基础、强化实践、学研结合、突出创新”的课程教学定位。实现课程资源共享及师生交流互动,达到丰富教学内容、优化教学过程设计、增加教学过程吸引力、培养学生创新意识的目的。

关键词： OBE理念以学生为中心全过程考核课程目标达成度

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信息化管理系统应用对医院医疗设备管理水平及医护人员设备使用体验的影响

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中国医疗器械信息 2024年第2期30卷 167-170页

作者：郑立彭震崔先晃张慧敏凃巧先李文兵李进东武汉经济技术开发区(汉南区)人民医院湖北武汉430090

目的:探讨信息化管理系统对医院医疗设备管理水平及医护人员设备使用体验的影响。方法:选取2021年1月~2021年6月本院75台医疗设备、5名设备科医护人员及122名医院设备使用医护人员作为对照组,行常规医疗设备管理;以2021年7月~2021年12... 详细信息

目的:探讨信息化管理系统对医院医疗设备管理水平及医护人员设备使用体验的影响。方法:选取2021年1月~2021年6月本院75台医疗设备、5名设备科医护人员及122名医院设备使用医护人员作为对照组,行常规医疗设备管理;以2021年7月~2021年12月本院75台医疗设备、5名设备科医护人员及128名医院设备使用医护人员作为试验组,应用信息化管理系统实施医疗设备管理。比较信息化管理实施前后医疗设备检查合格率、设备管理质量评分、设备维护管理情况、医护人员设备使用体验及设备经济效益。结果:试验组设备检查合格率、设备管理质量各项评分、设备预防性维修率及维修后管理率高于对照组,差异有统计学意义(P<0.05);试验组故障处理率低于对照组,差异显著(P<0.05);试验组设备经济效益优于对照组,差异有统计学意义(P<0.05);试验组设备使用医护人员总满意率高于对照组,差异有统计学意义(P<0.05)。结论:信息化管理系统能够促进医院医疗设备管理水平提高,并可改善医护人员设备使用体验及设备经济效益。

关键词：信息化管理系统医疗设备医护人员设备使用体验

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