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合金元素对激光熔覆高熵合金涂层硬度影响的研究进展

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精密成形工程 2024年第5期16卷 201-224页

作者：林添祥冯美艳练国富陈昌荣兰如清福建理工大学机械与汽车工程学院福州350118

激光熔覆技术采用高能量密度的激光作为工艺的能量来源,能够对工件表面进行改性和修复,显著地改善了基体的表面力学性能,从而有效地延长了产品的生命周期。激光熔覆是制备高熵合金的典型工艺之一,采用该技术并且添加合适的合金元素可以... 详细信息

激光熔覆技术采用高能量密度的激光作为工艺的能量来源,能够对工件表面进行改性和修复,显著地改善了基体的表面力学性能,从而有效地延长了产品的生命周期。激光熔覆是制备高熵合金的典型工艺之一,采用该技术并且添加合适的合金元素可以制备具备卓越性能的高熵合金涂层。为清晰地阐明加入元素后增强激光熔覆高熵合金涂层硬度的作用机制,首先综述了目前国内外在激光熔覆过程中加入常见元素所制备的高熵合金涂层硬度性能的研究现状,其中高熵合金有特殊的“4种效应”,对金属间化合物有促进作用,其内部微观结构一般为FCC、BCC或者HCP等固溶相,通常通过固溶强化、沉淀强化和分散强化来强化,并且激光熔覆法会使高熵合金涂层快速冷却,从而显著改善合金的力学性能。其次,分析了金属与非金属两大类元素对激光熔覆制备高熵合金涂层硬度强化的机理,总结了金属元素与非金属元素的添加对高熵合金涂层硬度的影响规律。最后,针对激光熔覆制备高熵合金涂层硬度性能的改进,总结出了有效的方法,并对其未来发展进行了展望。研究结果揭示了激光熔覆高熵合金涂层硬度强化的理论基础,为该领域的进一步发展提供了理论依据。

关键词：激光熔覆高熵合金硬度影响机理金属元素非金属元素

Spatiotemporal variation and evaluation of agriculture green development: a case study of Hainan Province, China

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 83-99页

作者： tianxiang YU Jichen ZHOU lin MA Fusuo ZHANG Zed RENGEL William JDAVIES Jianbo SHEN Department of Plant Nutrition College of Resources and Environmental SciencesCenter for ResourcesEnvironment and Food SecurityKey Laboratory of Plant-Soil interactionsMOENational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Sanya Institute of China Agricultural University Sanya 572025China Soil Physics and Land Management Group Wageningen UniversityP.O.Box 476700 AA Wageningenthe Netherlands Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Soil Science and Plant Nutrition UWA School of Agriculture and EnvironmentThe University of Western AustraliaPerth WA 6009Australia Institute for Adriatic Crops and Karst Reclamation 21000 SplitCroatia Lancaster Environment Centre University of LancasterLancaster LA14YQUK

The realization of green and sustainable development of agriculture is the common pursuit all over the world. Agriculture green development(AGD)program has been proposed as a sustainable development strategy in China,but insufficient is known about the quantitative evaluation of spatiotemporal variation in AGD at the regional scale. This study aimed to assess spatiotemporal patterns in AGD at the county/city-based regional level. For this purpose, a systematic index evaluation system was developed to assess the performance of socioeconomic, food production and environmental components in a key economic region(Hainan Province) of China. Hainan improved its AGD index(representing the overall performance toward achieving AGD) from 38.8 in 1988 to 40.9 in 2019. The socioeconomic development and agricultural productivity have improved with time;environmental quality declined due to overuse of chemicals from 1988 to 2013, but steadily improved after 2013, indicating positive effects of reducing chemical input. There was a higher AGD index in the coastal vs. central regions and the southern vs. northern regions. Scenarios featuring improved nutrient management or optimized diet structure and reduced waste improved economic benefits and social productivity while concurrently reducing environmental degradation. These results provide new insights for the future development of green and sustainable agriculture and formulation of agricultural policies in Hainan Province of China and even other developing countries that are facing or will soon face similar challenges.

关键词： Agriculture environmental impact green and sustainable development Hainan Province index evaluation system

Multiple valence states of Fe boosting SERS activity of Fe_(3)O_(4) nanoparticles and enabling effective SERS-MRI bimodal cancer imaging

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Fundamental Research 2024年第4期4卷 858-867页

作者： Jie lin Xuehua Ma Anran Li Ozioma Udochukwu Akakuru Chunshu Pan Meng He Chenyang Yao Wenzhi Ren Yanying Li Dinghu Zhang Yi Cao tianxiang Chen Aiguo Wu Cixi Institute of Biomedical Engineering International Cooperation Base of Biomedical Materials Technology and ApplicationChinese Academy of Science Key Laboratory of Magnetic Materials and DevicesZhejiang Engineering Research Center for Biomedical MaterialsNingbo Institute of Materials Technology and EngineeringCASNingbo315201China School of Engineering Medicine Key Laboratory of Big Data-Based Precision Medicine(Beihang University)Ministry of Industry and Information TechnologyBeihang UniversityBeijing100191China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516000China University of Chinese Academy of Sciences Bejing 100049China

Developing novel nanoparticle-based bioprobes utilized in clinical settings with imaging resolutions ranging from cell to tissue levels is a major challenge for tumor diagnosis and ***,an optimized strategy for designing a Fe_(3)O_(4)-based bioprobe for dual-modal cancer imaging based on surface-enhanced Raman scattering(SERS)and magnetic resonance imaging(MRI)is *** SERS activity of ultrasmall Fe_(3)O_(4) nanoparticles(NPs)was discovered,and a 5×10^(-9)M limit of detection for crystal violet molecules was successfully *** high-efficiency interfacial photon-induced charge transfer in Fe_(3)O_(4) NPs was promoted by multiple electronic energy levels ascribed to the multiple valence states of Fe,which was observed using ultraviolet-visible diffuse reflectance *** functional theory calculations were utilized to reveal that the narrow band gap and high electron density of states of ultrasmall Fe_(3)O_(4) NPs significantly boosted the vibronic coupling resonances in the SERS system upon *** subtypes of cancer cells were accurately recognized via high-resolution SERS imaging in vitro using the prepared Feg Og-based bioprobe with high sensitivity and good ***,Fe_(3)O_(4)-based bioprobes simultaneously exhibited T,-weighted MRI contrast enhancement with an active targeting capability for tumors in *** the best of our knowledge,this is the first report on the use of pure semiconductor-based SERS-MRI dual-modal nanoprobes in tumor imaging in vivo and in vitro,which has been previously realized only using semiconductor-metal complex *** non-metallic materials with SERS-MRI dual-modal imaging established in this report are a promising cancer diagnostic platform,which not only showed excellent performance in early tumor diagnosis but also possesses great potential for image-guided tumor treatment.

关键词： Fe_(3)O_(4)NPs SERS-MRI dual-modal nanoprobes PICT Multiple valence states Cancer diagnosis

Agriculture green development in China: insights and advances

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 5-19,I0005页

作者： Jianbo SHEN Qichao ZHU Yong HOU Wen-Feng CONG Wen XU Jiuliang XU Zhichao AN Xiaoqiang JIAO Kai ZHANG tianxiang YU lin MA Oene OENEMA William J.DAVIES Fusuo ZHANG State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Wageningen Environmental Research Wageningen University&ResearchWageningen6700 AAthe Netherlands Lancaster Environment Centre University of LancasterLancasterLA14YQUK

Reconciling the tasks of producing adequate amounts of nutritious food for the increasing global population while preserving the environment and natural ecosystems simultaneously is an enormous challenge. The concept of agriculture green development(AGD) and the necessary governmental policies were developed to address the aforementioned challenge in China and to help achieve the related global sustainable development goals. Agriculture green development emphasizes the synergy between green and development;current agriculture has to transform from the intensive farming with high inputs, high environmental impacts and low resource-use efficiency to a more sustainable agriculture, in order to ensure an adequate supply of nutritious food while delivering environmental integrity, improved economic profitability,and social equity. A research program on AGD was established by China Agricultural University with four research themes, namely: green crop production, green integrated crop-animal production, green food and industry,and green ecological environment and ecosystem services, to provide a scientific basis for future developments and to facilitate the implementation of AGD in practice. AGD requires a multistakeholder approach, fueled by innovative and interdisciplinary research. Joint actions have to be taken by governments, farmers, supply industries, consumers, educators, extension services and researchers to support AGD. This requires strong coordination and public awareness campaigns. This review presents the progress that has been made over the past 5 years and makes recommendations for more research and development, in order to better deliver agricultural green and sustainable development on national and international scales.

关键词： Agriculture ecosystem services environmental protection food security green development multi-sectoral cooperation sustainable development

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大型压力输水管道泄漏监测方法的试验研究

振动与冲击 2021年第5期40卷 136-142页

作者：林天翔冯少孔叶冠林朱新民车爱兰上海交通大学船舶海洋与建筑工程学院上海200240 中国水利水电科学研究院北京100038 流域水循环模拟与调控国家重点试验室北京100038

为研究一种针对大型压力输水管道泄漏问题的在线监测方法,设计了4种不同压力工况(0.2 MPa、0.4 MPa、0.6 MPa、0.8 MPa)和4种不同泄漏孔直径工况(2 mm、4 mm、8 mm、14 mm)的管道模型试验。试验通过控制阀门开闭、阀门孔径大小和输水管... 详细信息

为研究一种针对大型压力输水管道泄漏问题的在线监测方法,设计了4种不同压力工况(0.2 MPa、0.4 MPa、0.6 MPa、0.8 MPa)和4种不同泄漏孔直径工况(2 mm、4 mm、8 mm、14 mm)的管道模型试验。试验通过控制阀门开闭、阀门孔径大小和输水管压力变化来模拟实际运行管道的泄漏状态,并用水声检波器采集泄漏状态和非泄漏状态下的管道噪声数据来比较信号差异。经过分析,推导出了泄漏孔面积、管道压力与管道噪声信号振幅三者的关系。试验结果表明,通过利用水声检波器监测管道噪声变化进而监测管道泄漏是可行的,且泄漏信号主要由偶极子声源组成,泄漏状态下振幅随泄漏孔面积和管道运行压力均呈幂函数的关系增长。

关键词：压力管道泄漏监测理论模型模拟试验爆管预警

冲击映像法及其在超长距离顶管施工泥浆套检测中的应用

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土木与环境工程学报（中英文） 2022年第5期44卷 148-156页

作者：林天翔叶冠林王祺冯少孔上海交通大学船舶海洋与建筑工程学院上海200240 上海隧道工程有限公司上海200082

泥浆减阻是超长距离顶管施工中的一项关键技术,泥浆套厚度与工程质量息息相关。基于冲击映像法的基本原理,提出一种精确掌握顶管施工注浆充盈状况的快速检测方法,并通过模型试验和现场试验对检测方法的有效性进行研究。根据模型试验结果... 详细信息

泥浆减阻是超长距离顶管施工中的一项关键技术,泥浆套厚度与工程质量息息相关。基于冲击映像法的基本原理,提出一种精确掌握顶管施工注浆充盈状况的快速检测方法,并通过模型试验和现场试验对检测方法的有效性进行研究。根据模型试验结果,将归一化冲击响应强度作为反映泥浆充盈状况的评价指标,成功应用于苏州一大型引水工程中。研究表明:较传统压力观测法,冲击映像法在检测泥浆套厚度方面有明显的优越性,有效提高了检测效率和高阻力区的识别能力,据此对泥浆薄弱区进行定点补浆,节约了施工成本,可在同类工程中推广使用。

关键词：冲击映像法顶管施工泥浆套无损检测

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Effects of memantine on amyloid oligomer-induced impairment of synapticplasticity in vitro and in vivo

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Effects of memantine on amyloid oligomer-induced impairment ...

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： tianxiang DENG,Ruyi lin,Guilan LIU,Shujun XU,Xaiowei CHEN,Xiaofei WEI,Qinwen WANG~* Medical School,Ningbo University,Ningbo 315211,China

＜正＞Soluble amyloid-P protein（Aβ） plays a central pathogenic role in Alzheimer’s disease（AD）.Memantine,a low-affinity N-methyl-D-aspartate receptor（NMDAR） antagonist,exerts neural protective effects in *** this study, we investigated protection of memantine against the neurotoxicity of oligomeric Aβusing electrophysiology methods in vitro and in vivo and behavioral *** vitro,incubation of Aβ1-42 oligomers（500 nM） for 40 min prior to HFS strongly prevented *** inhibition can be partially reversed by an appropriate dose of mementine（20 mg/kg,i.p.） treatment for 7 ***,animals treated with a higher dose（40 mg/kg/day,i.p.） of memantine showed complete abolishment of LTP ***,inhibition of LTP by Aβ1-42 is partially restored when we pretreated with memantine（1μM） for 2 h,but alone treatment use this concentration of memantine for 2 h before HFS would partial inhibited the induction of *** vivo,we found acute injection of soluble Aβ1-42（40 pmol in 5μL,i.e.v.） alone 10 min before HFS inhibited LTP, the inhibitory effect of Aβ1-42 was partially prevented when 10 mg/kg memantine was injected 30 min before Aβ1- *** injection of twice this dose（20 mg/kg） alone completely inhibited *** behavioral testing,systemic treatment with memantine（3 mg/kg,i.p） alone impaired performance of operant learning task,but Aβ1-42 failed to strongly increase perseveration errors when the rats also received an injection of the subthreshold dose of memantine （1 mg/kg） if injection of soluble Aβ1-42（60 pmol in 10μL） alone before testing expand errors *** findings indicate that memantine restore Aβoligomers-mediated inhibition of hippocampal LTP in a concentration-related manner both in vitro and in vivo,it also prevented disruptive effect of Aβ1-42 on learned behavior,differences does-related in vitro and in vivo may be due to the different experimental environments and brain regions（the dentate gyrus in vitro and CA1 area in vivo）.Thus

关键词： Aβ AD synapse plasticity NMDA memantine

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静电纺聚砜纤维的制备与吸油性能

东华大学学报（自然科学版） 2017年第3期43卷 328-334页

作者：郑天翔李想林金友曾泳春东华大学纺织学院上海201620 中国科学院上海应用物理研究所上海201204

针对海洋溢油问题,利用静电纺丝一步法制备不同质量分数的聚砜(PSF)纤维膜,扫描电镜结果发现纤维表面存在细微孔洞.对纤维形貌和结构包括纤维直径、纤维间孔隙率、纤维表面孔径分布、接触角、吸油倍率、保油率和油水分离等进行测试和表... 详细信息

针对海洋溢油问题,利用静电纺丝一步法制备不同质量分数的聚砜(PSF)纤维膜,扫描电镜结果发现纤维表面存在细微孔洞.对纤维形貌和结构包括纤维直径、纤维间孔隙率、纤维表面孔径分布、接触角、吸油倍率、保油率和油水分离等进行测试和表征,结果表明,随着PSF/N,N-二甲基甲酰胺(DMF)溶液质量分数的增大(从12%增大到18%),纤维中的珠状物逐渐消失,平均直径增大,纤维间孔隙率增大,纤维表面的孔径主要分布在10~100nm,水的接触角在131°~140°范围内,PSF纤维膜对菜籽油和机油的吸油倍率最高可达到37和50,对机油的保油率高达75%,同时具有良好的浮力与疏水亲油性.

关键词：静电纺丝聚砜纤维吸油倍率

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公交车鼓式制动器三层结构刹车片开发

非金属矿 2014年第5期37卷 81-83页

作者：林荣会孙夕香林天翔张敬辉青岛理工大学汽车与交通学院山东青岛266033

根据大型公交车的特点和降噪机理,开发了具有摩擦层、缓冲层和基层的3层结构刹车片。利用均匀设计和SAS软件对摩擦层的材料配方进行了优化,结果表明,优化后,摩擦层的摩擦磨损性能优异。对试制的三层结构刹车片进行了硬度、噪声和装车实... 详细信息

根据大型公交车的特点和降噪机理,开发了具有摩擦层、缓冲层和基层的3层结构刹车片。利用均匀设计和SAS软件对摩擦层的材料配方进行了优化,结果表明,优化后,摩擦层的摩擦磨损性能优异。对试制的三层结构刹车片进行了硬度、噪声和装车实验,结果表明,新开发刹车片无制动噪声;与市售同类型刹车片相比,其硬度低,使用寿命可提高约26%,原材料成本可降低约31%。

关键词：公交车鼓式制动器 3层结构刹车片噪声