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Plant Diseases and Pests 2024年第1期15卷 1-3,6页

作者： Zhenxing WU jianjian chen Tingzhen WANG Guihua LU Institute of Maize and Featured Upland Crops Zhejiang Academy of Agricultural SciencesDongyang 322100China

[Objectives]The paper was to explore the effects of low temperature stress on germination and physiological characteristics of different sweet maize varieties.[Methods]Taking Taitian 264,Zhexuetian 1 and Chaotian 4 as the research objects,the changes in germination potential,germination index,plant height,biomass,and antioxidant enzyme activity of maize seeds were studied under optimal temperature conditions(25℃)and low temperature stress conditions(10℃).[Results]Under 10℃stress,the germination rate and germination index of Taitian 264 were higher than that of Zhexuetian 1 and Chaotian *** low temperature stress,Taitian 264 exhibited the least reduction in height and biomass,while Zhexuetian 1 had the most ***,the SOD and POD activities of Taitian 264 were higher than that of Zhexuetian 1 and Chaotian 4 under both temperature conditions,while the MDA content of Taitian 264 was *** 264 showed strong germination ability against low temperature stress.[Conclusions]This study provides a basis for timely sowing practices of sweet maize in agricultural production.

关键词： Sweet maize Low temperature stress Germination Antioxidant enzyme

独立促销还是联合促销?电商平台自营产品与第三方产品促销策略

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系统工程理论与实践 2024年第3期44卷 969-985页

作者：陈建建冯楠冯海洋张晗悦江西财经大学信息管理学院南昌330032 天津大学管理与经济学部天津300072 天津大学复杂管理系统实验室天津300072

近年来,电商平台自营商家与第三方商家经常选择独立促销或者联合促销增加产品销量.与独立促销不同,以“跨店满减”为代表的联合促销活动一般由平台发起,但平台企业制定的联合促销力度所产生的成本由自营商家和第三方商家共同承担.考虑... 详细信息

近年来,电商平台自营商家与第三方商家经常选择独立促销或者联合促销增加产品销量.与独立促销不同,以“跨店满减”为代表的联合促销活动一般由平台发起,但平台企业制定的联合促销力度所产生的成本由自营商家和第三方商家共同承担.考虑双边市场环境下不同促销模式的特点,构建三阶段博弈模型探讨佣金率、促销引起的市场扩张效应等因素对产品定价决策、最优联合促销成本分摊比例以及促销模式选择的影响.结果表明:1)当且仅当平台的佣金率和联合促销成本分摊比例均较高或者较低时,联合促销情形下的产品原价和促销力度均高于其独立促销情形.当市场扩张效应较强时,消费者应该避免在促销活动期间购买产品.2)无论在垄断还是竞争情境下,当且仅当第三方卖家开展促销活动的成本较高,其市场扩张效应较弱且联合促销成本分摊比例适中时,平台企业和第三方卖家实施联合促销策略优于独立促销策略和非促销策略.3)在联合促销活动中,当佣金率较高时,第三方卖家将单独支付联合促销力度产生的成本;否则,联合促销成本由平台和第三方卖家共同承担,并且当佣金率较低时,平台支付的联合促销成本分摊比例随着市场扩张效应的增强而减小.

关键词：双边平台自营产品联合促销策略市场扩张效应联合促销成本分摊比例

职业教育数字化课程的内涵价值、实践困境与推进策略

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职教论坛 2024年第6期40卷 62-69页

作者：秦国锋劳晶晶陈健健糜沛纹李铭广西师范大学职业技术师范学院广西桂林541001 南宁市第四职业技术学校广西南宁530021

职业教育结构正在被数字技术优化和重构,急需数字化推动课程从内到外的系统性变革和结构性创新。数字化课程以数字技术驱动为核心,以课程平台为依托,以数字素养培养为侧内生,以高质量发展为目标的内在要义;数字化课程在结构特征上要融... 详细信息

职业教育结构正在被数字技术优化和重构,急需数字化推动课程从内到外的系统性变革和结构性创新。数字化课程以数字技术驱动为核心,以课程平台为依托,以数字素养培养为侧内生,以高质量发展为目标的内在要义;数字化课程在结构特征上要融入数字技术,逐步实现数字化、智能化、社会化。目前职业教育数字化课程建设面临数字技术加剧课程目标的滞后性、课程内容的选择与组织缺乏数字技术的融合、数字技术加重课程实施负担、融入数据的课程评价机制有待完善等多重实践困境。基于此,提出职业教育数字化课程的推进策略:契合技术变革转型职业教育课程目标,重塑课程内容供给与需求的衔接关系,充分利用数字技术推进课程实施,建立数据中心评价机制。

关键词：数字化课程开发数字化技术课程改革

Correlation between Subliminal Depression and the Quality of Life in Patients Preliminarily Diagnosed with Breast Cancer

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Yangtze Medicine 2019年第1期3卷 10-18页

作者： jianjian chen Hong Wang Haiyuan Zhang Juan Ding School of Medicine Yangtze University Jing Zhou China Second Clinical Medicine School of Yangtze University Breast Department of Jingzhou Central Hospital Jing Zhou China

Objective: To investigate the subthreshold depression and the quality of life in patients preliminarily diagnosed with breast cancer, and to explore their relationship. Methods: A total of 210 patients preliminarily diagnosed breast cancer were recruited by convenience sampling method to complete the self-made general questionnaire, Center for Epidemiological Studies Depression Scale (CES-D), Hamilton Rating Scale for Depression and Functional Assessment of Cancer Therapy-Breast (FACT-B). Results: The incidence rates of subthreshold depression was 48.6% in patients preliminarily diagnosed breast cancer, the total score of FACT-B in patients with subthreshold depression and non-subthreshold depression was (73.92 ±17.62) and (86.74 ±16.15). The total score of CES-D was significantly negatively correlated to the total score and factor scores of FACT-B (p Conclusion: The incidence rate of subthreshold depression in preliminarily diagnosed breast cancer patients is high, and it is closely related to the quality of life, so we should pay attention to the psychological status of preliminarily diagnosed breast cancer patients, to increase the psychological intervention, than improve their quality of life.

关键词： Patients Preliminarily Diagnosed Breast Cancer Subthreshold Depression Quality of Life

Large low-field reversible magnetocaloric effect in K_(3)Gd(PO_(4))_(2) at sub-Kelvin temperature

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Journal of Rare Earths 2024年第6期42卷 1087-1092,I0003页

作者： Haojie Wang Zhaojun Mo jianjian Gong Heng Tu Guochun Zhang Jun Shen School of Rare Earths University of Science and Technology of ChinaHefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China Center for Crystal Research and Development Key Laboratory of Functional Crystals and Laser TechnologyKey Laboratory of CryogenicsTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing100190China Department of Energy and PowerEngineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China

We synthesized a potassium gadolinium phosphate K3Gd(PO_(4))_(2)with monoclinic structure(P2_(1/m))by the high-temperature solid-state reaction *** lattice constants obtained by Rietveld refinements of XRD curve are a=0.7411 nm,b=0.5624 nm,and c=0.9433 *** and magnetocaloric properties of K_(3)Gd(PO_(4))_(2)were investigated in *** magnetic phase transition temperature of K3Gd(PO_(4))2 was determined by ultra-low temperature testing to be 0.58 K.K_(3)Gd(PO_(4))2 exhibits large magnetic entropy changes(-ΔSM).The maximum-ΔSM are 20.2 and 29.4 J/(kg·K)in the magnetic field variation(ΔH)of 1 and 2 T,respectively,which are larger than that of the commercial Gd_(3)Ga_(5)O_(12)(GGG).The maximum adiabatic temperature change(ΔT_(ad))reaches 5.91 K under a magnetic field change(ΔH)of 1 T.K_(3)Gd(PO_(4))_(2)is a potential magnetic refrigeration material for obtaining sub-Kelvin temperatures.

关键词： Ultra-low temperature Magnetocaloric effect Magnetic entropy change Magnetic refrigeration Rare earths

Elliptical vibration chiseling:a novel process for texturing ultra-high-aspect-ratio microstructures on the metallic surface

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International Journal of Extreme Manufacturing 2024年第2期6卷 449-467页

作者： Zhiwei Li Jianfu Zhang Zhongpeng Zheng Pingfa Feng Dingwen Yu jianjian Wang State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Beijing Key Laboratory of Precision/Ultra-precision Manufacturing Equipments and Control Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Division of Advanced Manufacturing Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055People’s Republic of China

High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon ***,the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing *** study proposes a novel cutting-based process,namely elliptical vibration chiseling(EV-chiseling),for the high-efficiency texturing of surface microstructures with an ultrahigh aspect *** conventional cutting,EV-chiseling superimposes a microscale EV on a backward-moving *** tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material *** to the tool’s backward movement,the chip is left on the material surface to form a microstructure rather than falling *** one microstructure is generated in one vibration cycle,the process can be highly efficient using ultrafast(>1 kHz)tool vibration.A finite element analysis model is established to explore the process mechanics of ***,a mechanistic model of the microstructured surface generation is developed to describe the microstructures’aspect ratio dependency on the process ***,surface texturing tests are performed on copper to verify the efficacy of *** micro ribs with a spacing of 1–10μm and an aspect ratio of 2–5 have been successfully textured on *** with the conventional EV-cutting that uses a forward-moving tool,EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 *** experimental results also verify the accuracy of the developed surface generation model of ***,the effects of elliptical trajectory,depth of cut,tool shape,and tool edge radius on the surface generation of micro ribs have been discussed.

关键词： metallic microstructure high aspect ratio backward-moving cutting vibration cutting chiseling material deformation

海洋环境下关键摩擦副材料的摩擦学研究现状与展望

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材料导报 2016年第15期30卷 85-91,112页

作者：文怀兴孙建建陈威陕西科技大学机电工程学院西安710021

海洋是人类生存的基本空间,也是保证人类社会持续发展的宝库。关于海洋环境下材料的摩擦学研究,不仅促进了海洋工程装备的开发,而且也为海洋工程装备的关键摩擦副材料提供了有力支撑。但海洋环境下的摩擦磨损严重制约了海洋专用材料的... 详细信息

海洋是人类生存的基本空间,也是保证人类社会持续发展的宝库。关于海洋环境下材料的摩擦学研究,不仅促进了海洋工程装备的开发,而且也为海洋工程装备的关键摩擦副材料提供了有力支撑。但海洋环境下的摩擦磨损严重制约了海洋专用材料的应用与发展,主要原因是海水介质复杂,以及腐蚀与摩擦的交互作用等。因此,研究和探讨海洋环境下关键摩擦副材料的摩擦学是提高我国海洋工程装备整体水平的重要途径。对海洋环境下关键摩擦副材料的摩擦学研究进行汇总与分析,着重介绍了金属与金属配副、陶瓷与金属配副、聚合物与金属配副、聚合物与陶瓷配副等在海水环境下的摩擦学研究现状,并结合摩擦副材料的摩擦学研究现状及发展趋势,对海洋环境下关键摩擦副材料的摩擦学研究进行了展望。

关键词：海洋环境关键摩擦副摩擦学腐蚀磨损

快感的生产:当下中国喜剧电影的“互文性”机制

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当代电影 2022年第7期 144-150页

作者：陈箭箭深圳大学艺术学部戏剧影视学院

作为大众文化的重要组成部分,喜剧电影以其对“快感”的源源不断的生产而备受关注。媒介化时代,大众文化生产愈发凸显后现代文化的诸多特征,并呈现出新的面貌。我们对中国喜剧电影的考察不应仅停留在创作技术层面,而应深入文化肌理,与... 详细信息

作为大众文化的重要组成部分,喜剧电影以其对“快感”的源源不断的生产而备受关注。媒介化时代,大众文化生产愈发凸显后现代文化的诸多特征,并呈现出新的面貌。我们对中国喜剧电影的考察不应仅停留在创作技术层面,而应深入文化肌理,与变化着的社会同频共振,把握时代的情感结构。当下中国喜剧电影生产的“互文性”机制体现为多个维度,比如跨媒介性、文化实践性、社会映射性,等等。对这些互文形式的分析,有助于我们理解当下中国喜剧电影生产的复杂机制,进而打开喜剧电影的美学与文化空间。

关键词：快感大众文化后现代文化中国喜剧电影互文性

Theoretical investigations on the growth of graphene by oxygenassisted chemical vapor deposition

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Nano Research 2024年第6期17卷 4645-4650页

作者： Xiaoli Sun Chaojie Yu Yujia Yang Zhihao Li jianjian Shi Wanjian Yin Zhongfan Liu Beijing Graphene Institute(BGI) Beijing 100095China School of Physics and Electronics Shandong Normal UniversityJinan 250014China College of Energy Soochow Institute for Energy and Materials InnovationsLight Industry Institute of Electrochemical Power SourcesSUDA-BGI Collaborative Innovation CenterSoochow UniversitySuzhou 215006China School of Electronic Engineering Chengdu Technological UniversityChengdu 611730China Center for Nanochemistry Beijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Recently,graphene has drawn considerable attention in the field of electronics,owing to its favorable conductivity and high carrier *** to the industrialization of graphene is its high-quality microfabrication via chemical vapor ***,many problems remain in its preparation,such as the not fully understood cracking mechanism of the carbon source,the mechanism of its substrate oxidation,and insufficient defect repair *** help close this capability gap,this study leverages density functional theory to explore the role of O in graphene *** effects of Cu substrate oxidation on carbon source cracking,nucleation barriers,crystal nucleus growth,and defect repairs are *** was found to reduce energy change during dehydrogenation,rendering the process ***,the adsorbed O in graphene or its Cu substrate can promote defect repair and edge growth.

关键词： density functional theory oxygen-assisted graphene growth chemical vapor deposition Cu substrate

当下国产喜剧电影的“游戏性”:文化隐喻与实践方式

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当代电影 2023年第8期 67-72页

作者：陈箭箭深圳大学艺术学部戏剧影视学院

本文尝试在当下国产喜剧电影研究中引入“游戏”的视角,提出一种研究假设:游戏的丰富文化内涵,可以为喜剧电影创作提供一套文化隐喻的框架。首先,从哲学与文化的角度阐发喜剧与游戏的发生机制,认为二者最初都是戴着“面具”的仪式性狂欢... 详细信息

本文尝试在当下国产喜剧电影研究中引入“游戏”的视角,提出一种研究假设:游戏的丰富文化内涵,可以为喜剧电影创作提供一套文化隐喻的框架。首先,从哲学与文化的角度阐发喜剧与游戏的发生机制,认为二者最初都是戴着“面具”的仪式性狂欢,彰显了一种自由、天真与不严肃性;其次,以中国近些年的穿越喜剧、变身喜剧为文本考察对象,结合现代游戏的相关实践,阐发游戏中“再来一次”“角色扮演”等隐喻为喜剧电影提供的创作逻辑;然后,从剧本杀、沉浸剧场等当下体验类游戏介入喜剧创作的实践出发,基于现代生存哲学,提出“一起玩”的观念,将游戏的参与意识注入喜剧电影的文化之中。

关键词：喜剧电影游戏性天真角色扮演文化隐喻实践