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Solidworks应用于《机械设计课程设计》课程教学 被引量:1
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作者 余丽 伍哲 +1 位作者 施冠羽 郭文勇 《机械设计与制造》 北大核心 2024年第1期20-22,29,共4页
在《机械设计课程设计》课程教学中引入计算机辅助设计软件Solidworks作为辅助教学手段,通过该软件特有的运动仿真功能,建立闭式齿轮传动、锥齿轮传动、开式齿轮传动、链轮绞盘机构的虚拟模型,装配各传动机构,检查、优化设计方案,实现... 在《机械设计课程设计》课程教学中引入计算机辅助设计软件Solidworks作为辅助教学手段,通过该软件特有的运动仿真功能,建立闭式齿轮传动、锥齿轮传动、开式齿轮传动、链轮绞盘机构的虚拟模型,装配各传动机构,检查、优化设计方案,实现了传动装置的运动仿真,完成了该锚机系缆装置的模拟设计,锻炼了学生的软件使用技能,增强了学生对理论知识的深入理解和应用,激发了学生对机械课程深入学习的兴趣,提高了学生的机械设计水平,同时有助于培养学生工程实践和综合应用能力,达到了预期的教学效果。 展开更多
关键词 机械设计课程设计 SOLIDWORKS 计算机辅助设计 课程教学 虚拟仿真 装配设计
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Carbon-based interface engineering and architecture design for high-performance lithium metal anodes
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作者 Na Zhu yuxiang Yang +3 位作者 yu li Ying Bai Junfeng Rong Chuan Wu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期207-235,共29页
Metallic lithium(Li)is considered the“Holy Grail”anode material for the nextgeneration of Li batteries with high energy density owing to the extraordinary theoretical specific capacity and the lowest negative electr... Metallic lithium(Li)is considered the“Holy Grail”anode material for the nextgeneration of Li batteries with high energy density owing to the extraordinary theoretical specific capacity and the lowest negative electrochemical potential.However,owing to inhomogeneous Li-ion flux,Li anodes undergo uncontrollable Li deposition,leading to limited power output and practical applications.Carbon materials and their composites with controllable structures and properties have received extensive attention to guide the homogeneous growth of Li to achieve high-performance Li anodes.In this review,the correlation between the behavior of Li anode and the properties of carbon materials is proposed.Subsequently,we review emerging strategies for rationally designing high-performance Li anodes with carbon materials,including interface engineering(stabilizing solid electrolyte interphase layer and other functionalized interfacial layer)and architecture design of host carbon(constructing three-dimension structure,preparing hollow structure,introducing lithiophilic sites,optimizing geometric effects,and compositing with Li).Based on the insights,some prospects on critical challenges and possible future research directions in this field are concluded.It is anticipated that further innovative works on the fundamental chemistry and theoretical research of Li anodes are needed. 展开更多
关键词 carbon materials DENDRITES HOSTS interfacial layers Li metal anodes
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Bifunctional TiO_(2-x)nanofibers enhanced gel polymer electrolyte for high performance lithium metal batteries
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作者 Yixin Wu Zhen Chen +6 位作者 Yang Wang yu li Chunxing Zhang Yihui Zhu Ziyu yue Xin liu Minghua Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期437-448,I0011,共13页
Exploration of advanced gel polymer electrolytes(GPEs)represents a viable strategy for mitigating dendritic lithium(Li)growth,which is crucial in ensuring the safe operation of high energy density Li metal batteries(L... Exploration of advanced gel polymer electrolytes(GPEs)represents a viable strategy for mitigating dendritic lithium(Li)growth,which is crucial in ensuring the safe operation of high energy density Li metal batteries(LMBs).Despite this,the application of GPEs is still hindered by inadequate ionic conductivity,low Li^(+)transference number,and subpar physicochemical properties.Herein,Ti O_(2-x)nanofibers(NF)with oxygen vacancy defects were synthesized by a one-step process as inorganic fillers to enhance the thermal/mechanical/ionic-transportation performances of composite GPEs.Various characterizations and theoretical calculations reveal that the oxygen vacancies on the surface of Ti O_(2-x)NF accelerate the dissociation of Li PF_6,promote the rapid transfer of free Li^(+),and influence the formation of Li F-enriched solid electrolyte interphase.Consequently,the composite GPEs demonstrate enhanced ionic conductivity(1.90m S cm^(-1)at room temperature),higher lithium-ion transference number(0.70),wider electrochemical stability window(5.50 V),superior mechanical strength,excellent thermal stability(210℃),and improved compatibility with lithium,resulting in superior cycling stability and rate performance in both Li||Li,Li||Li Fe PO_(4),and Li||Li Ni_(0.8)Co_(0.1)Mn_(0.1)O_(2)cells.Overall,the synergistic influence of nanofiber morphology and enriched oxygen vacancy structure of fillers on electrochemical properties of composite GPEs is comprehensively investigated,thus,it is anticipated to shed new light on designing high-performance GPEs LMBs. 展开更多
关键词 Nanofibers fillers Oxygen vacancies Gel polymer electrolytes Lithium metal batteries
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Fecal microbiota transplantation for treatment of non-alcoholic fatty liver disease:Mechanism,clinical evidence,and prospect
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作者 Xiao-Xia Qiu Sheng-li Cheng +4 位作者 Yan-Hui liu yu li Rui Zhang Nan-Nan li Zheng li 《World Journal of Gastroenterology》 SCIE CAS 2024年第8期833-842,共10页
The population of non-alcoholic fatty liver disease(NAFLD)patients along with relevant advanced liver disease is projected to continue growing,because currently no medications are approved for treatment.Fecal microbio... The population of non-alcoholic fatty liver disease(NAFLD)patients along with relevant advanced liver disease is projected to continue growing,because currently no medications are approved for treatment.Fecal microbiota transplantation(FMT)is believed a novel and promising therapeutic approach based on the concept of the gut-liver axis in liver disease.There has been an increase in the number of pre-clinical and clinical studies evaluating FMT in NAFLD treatment,however,existing findings diverge on its effects.Herein,we briefly summarized the mechanism of FMT for NAFLD treatment,reviewed randomized controlled trials for evaluating its efficacy in NAFLD,and proposed the prospect of future trials on FMT. 展开更多
关键词 Non-alcoholic fatty liver disease Fecal microbiota transplantation Randomized controlled trial MECHANISM EFFICACY
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Reliable ferroelectricity down to cryogenic temperature in wakeup free Hf_(0.5)Zr_(0.5)O_(2)thin films by thermal atomic layer deposition
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作者 Shuyu Wu Rongrong Cao +6 位作者 Hao Jiang yu li Xumeng Zhang Yang Yang Yan Wang Yingfen Wei Qi liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期33-37,共5页
The performance and reliability of ferroelectric thin films at temperatures around a few Kelvin are critical for their application in cryo-electronics.In this work,TiN/Hf_(0.5)Zr_(0.5)O_(2)/TiN capacitors that are fre... The performance and reliability of ferroelectric thin films at temperatures around a few Kelvin are critical for their application in cryo-electronics.In this work,TiN/Hf_(0.5)Zr_(0.5)O_(2)/TiN capacitors that are free from the wake-up effect are investigated systematically from room temperature(300 K)to cryogenic temperature(30 K).We observe a consistent decrease in permittivity(εr)and a progressive increase in coercive electric field(Ec)as temperatures decrease.Our investigation reveals exceptional stability in the double remnant polarization(2P_(r))of our ferroelectric thin films across a wide temperature range.Specifically,at 30 K,a 2P_(r)of 36μC/cm^(2)under an applied electric field of 3.0 MV/cm is achieved.Moreover,we observed a reduced fatigue effect at 30 K in comparison to 300 K.The stable ferroelectric properties and endurance characteristics demonstrate the feasibility of utilizing HfO_(2)based ferroelectric thin films for cryo-electronics applications. 展开更多
关键词 hafnia-zirconia solid solution FERROELECTRICITY cryogenic temperature wake-up effect
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Privacy-Preserving Federated Mobility Prediction with Compound Data and Model Perturbation Mechanism
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作者 Long Qingyue Wang Huandong +4 位作者 Chen Huiming Jin Depeng Zhu lin yu li li Yong 《China Communications》 SCIE CSCD 2024年第3期160-173,共14页
Human mobility prediction is important for many applications.However,training an accurate mobility prediction model requires a large scale of human trajectories,where privacy issues become an important problem.The ris... Human mobility prediction is important for many applications.However,training an accurate mobility prediction model requires a large scale of human trajectories,where privacy issues become an important problem.The rising federated learning provides us with a promising solution to this problem,which enables mobile devices to collaboratively learn a shared prediction model while keeping all the training data on the device,decoupling the ability to do machine learning from the need to store the data in the cloud.However,existing federated learningbased methods either do not provide privacy guarantees or have vulnerability in terms of privacy leakage.In this paper,we combine the techniques of data perturbation and model perturbation mechanisms and propose a privacy-preserving mobility prediction algorithm,where we add noise to the transmitted model and the raw data collaboratively to protect user privacy and keep the mobility prediction performance.Extensive experimental results show that our proposed method significantly outperforms the existing stateof-the-art mobility prediction method in terms of defensive performance against practical attacks while having comparable mobility prediction performance,demonstrating its effectiveness. 展开更多
关键词 federated learning mobility prediction PRIVACY
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Transformer-Aided Deep Double Dueling Spatial-Temporal Q-Network for Spatial Crowdsourcing Analysis
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作者 yu li Mingxiao li +2 位作者 Dongyang Ou Junjie Guo Fangyuan Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期893-909,共17页
With the rapid development ofmobile Internet,spatial crowdsourcing has becomemore andmore popular.Spatial crowdsourcing consists of many different types of applications,such as spatial crowd-sensing services.In terms ... With the rapid development ofmobile Internet,spatial crowdsourcing has becomemore andmore popular.Spatial crowdsourcing consists of many different types of applications,such as spatial crowd-sensing services.In terms of spatial crowd-sensing,it collects and analyzes traffic sensing data from clients like vehicles and traffic lights to construct intelligent traffic prediction models.Besides collecting sensing data,spatial crowdsourcing also includes spatial delivery services like DiDi and Uber.Appropriate task assignment and worker selection dominate the service quality for spatial crowdsourcing applications.Previous research conducted task assignments via traditional matching approaches or using simple network models.However,advanced mining methods are lacking to explore the relationship between workers,task publishers,and the spatio-temporal attributes in tasks.Therefore,in this paper,we propose a Deep Double Dueling Spatial-temporal Q Network(D3SQN)to adaptively learn the spatialtemporal relationship between task,task publishers,and workers in a dynamic environment to achieve optimal allocation.Specifically,D3SQNis revised through reinforcement learning by adding a spatial-temporal transformer that can estimate the expected state values and action advantages so as to improve the accuracy of task assignments.Extensive experiments are conducted over real data collected fromDiDi and ELM,and the simulation results verify the effectiveness of our proposed models. 展开更多
关键词 Historical behavior analysis spatial crowdsourcing deep double dueling Q-networks
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Preliminary report of the September 5,2022 M_(S) 6.8 Luding earthquake,Sichuan,China 被引量:1
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作者 Yanru An Dun Wang +12 位作者 Qiang Ma yueren Xu yu li Yingying Zhang Zhumei liu Chunmei Huang Jinrong Su Jilong li Mingxiao li Wenkai Chen Zhifan Wan Dengjie Kang Baoshan Wang 《Earthquake Research Advances》 CSCD 2023年第1期1-10,共10页
The 2022 M_(S)6.8 Luding earthquake is the strongest earthquake in Sichuan Province, Western China, since the 2017 M_(S)7.0 Jiuzhaigou earthquake. It occurred on the Moxi fault in the southeastern segment of the Xians... The 2022 M_(S)6.8 Luding earthquake is the strongest earthquake in Sichuan Province, Western China, since the 2017 M_(S)7.0 Jiuzhaigou earthquake. It occurred on the Moxi fault in the southeastern segment of the Xianshuihe fault, a tectonically active and mountainous region with severe secondary earthquake disasters. To better understand the seismogenic mechanism and provide scientific support for future hazard mitigation, we summarize the preliminary results of the Luding earthquake, including seismotectonic background, seismicity and mainshock source characteristics and aftershock properties, and direct and secondary damage associated with the mainshock.The peak ground displacements in the NS and EW directions observed by the nearest GNSS station SCCM are ~35 mm and ~55 mm, respectively, resulting in the maximum coseismic dislocation of 20 mm along the NWW direction, which is consistent with the sinistral slip on the Xianshuihe fault. Back-projection of teleseismic P waves suggest that the mainshock rupture propagated toward south-southeast. The seismic intensity of the mainshock estimated from the back-projection results indicates a Mercalli scale of Ⅷ or above near the ruptured area,consistent with the results from instrumental measurements and field surveys. Numerous aftershocks were reported, with the largest being M_(S)4.5. Aftershock locations(up to September 18, 2022) exhibit 3 clusters spanning an area of 100 km long and 30 km wide. The magnitude and rate of aftershocks decreased as expected, and the depths became shallower with time. The mainshock and two aftershocks show left-lateral strike-slip focal mechanisms. For the aftershock sequence, the b-value from the Gutenberg-Richter frequency-magnitude relationship, h-value, and p-value for Omori’s law for aftershock decay are 0.81, 1.4, and 1.21, respectively, indicating that this is a typical mainshock-aftershock sequence. The low b-value implies high background stress in the hypocenter region. Analysis from remote sensing satellite images and UAV data shows that the distribution of earthquake-triggered landslides was consistent with the aftershock area. Numerous small-size landslides with limited volumes were revealed, which damaged or buried the roads and severely hindered the rescue process. 展开更多
关键词 Luding earthquake Moxi fault Aftershock statistics Earthquake disasters Intensity map
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靶向敲除棉花GhAGL16高效sgRNA的筛选
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作者 雷建峰 尤扬子 +5 位作者 张锦恩 代培红 于莉 杜正阳 李月 刘晓东 《中国农业科学》 CAS CSCD 北大核心 2024年第6期1023-1033,共11页
【目的】AGL16是棉花MADS-box基因家族中一个重要的转录负调控因子,在抵御干旱和盐胁迫过程中发挥着重要作用。利用病毒介导的基因编辑技术(virus-induced gene editing,VIGE)筛选靶向敲除棉花GhAGL16的sgRNAs,并验证这些sgRNAs的特异性... 【目的】AGL16是棉花MADS-box基因家族中一个重要的转录负调控因子,在抵御干旱和盐胁迫过程中发挥着重要作用。利用病毒介导的基因编辑技术(virus-induced gene editing,VIGE)筛选靶向敲除棉花GhAGL16的sgRNAs,并验证这些sgRNAs的特异性,为定向创制棉花agl16突变体奠定重要基础。【方法】根据在棉花YZ-1中A亚组和D亚组上实际克隆GhAGL16的基因组序列,预测了3个能靶向敲除GhAGL16的sgRNAs;基于棉花叶皱缩病毒(cotton leaf crumple virus,CLCrV)介导的VIGE系统,构建3个CLCrV-AtU6-26::GhAGL16-sgRNAs表达载体;利用qPCR检测Cas9超表达(Cas9 over-expression,Cas9-OE)植株中Cas9的表达量,确定Cas9是否稳定遗传表达;将3个CLCrV-AtU6-26::GhAGL16-sgRNAs表达载体分别转化Cas9-OE棉花子叶,并通过PCR/RE方法检测3个靶点的突变情况;利用生物信息学方法分析3个GhAGL16-sgRNAs的二级结构;对突变植株进行Hi-TOM高通量测序,明确基因编辑效率。同时,对转化GhAGL16-sgRNA2的突变植株进行脱靶率鉴定,检测基因编辑的特异性。【结果】成功构建了3个能同时靶向敲除GhAGL16-A亚组和GhAGL16-D亚组序列的sgRNAs。对不同Cas9-OE植株中Cas9表达量检测结果表明,Cas9在不同Cas9-OE棉株中稳定表达。用3个CLCrV-AtU6-26::GhAGL16-sgRNAs表达载体转化Cas9-OE棉花子叶,PCR/RE突变检测结果表明,GhAGL16-sgRNA2可有效用于GhAGL16的靶向敲除,在棉花A亚组和D亚组靶位点上出现了不同碱基缺失的突变类型,而GhAGL16-sgRNA1和GhAGL16-sgRNA3是2个无效sgRNA。3个GhAGL16-sgRNAs的二级结构分析结果表明,GhAGL16-sgRNA1和GhAGL16-sgRNA3可能存在引导序列容易与其他序列发生配对并且不易解链的现象,干扰了引导序列对目标位点的识别,导致sgRNA无效。进一步量化GhAGL16-sgRNA2对GhAGL16的编辑效率,对每一株转化CLCrV-AtU6-26::GhAGL16-sgRNA2的Cas9-OE植株突变检测结果表明,在转化的9株Cas9-OE植株中有6株发生了突变,突变效率为66.67%。此外,Hi-TOM高通量测序结果表明,GhAGL16-sgRNA2对GhAGL16的编辑效率为13.69%—54.42%。脱靶率鉴定结果表明,预测的4个潜在脱靶位点都没有发现脱靶现象,说明GhAGL16-sgRNA2不仅具有高效的基因编辑效率,而且具有专一的基因编辑特异性。【结论】利用CLCrV介导的VIGE系统转化Cas9-OE棉花筛选获得1个能高效敲除GhAGL16的sgRNA,为定向创制棉花agl16突变体提供了理想的sgRNA。 展开更多
关键词 棉花 GhAGL16 sgRNA 突变体 VIGE 脱靶
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结球甘蓝CBF家族特征分析及低温诱导基因BoCBF1、BoCBF2a和BoCBF3表达分析
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作者 张伟 余方伟 +2 位作者 李建斌 于利 王神云 《江苏农业学报》 CSCD 北大核心 2024年第1期156-164,共9页
转录因子CBF在植物对低温胁迫的响应和增强植物的抗寒性方面发挥着重要作用。为分析结球甘蓝CBF家族成员的氨基酸序列特征,探究其是否受低温诱导表达,本研究利用结球甘蓝923全基因组数据库对其进行蛋白质理化特征、系统发育关系、编码... 转录因子CBF在植物对低温胁迫的响应和增强植物的抗寒性方面发挥着重要作用。为分析结球甘蓝CBF家族成员的氨基酸序列特征,探究其是否受低温诱导表达,本研究利用结球甘蓝923全基因组数据库对其进行蛋白质理化特征、系统发育关系、编码基因结构以及2℃低温胁迫下编码基因表达水平分析。结果表明,共鉴定到7个BoCBF基因,系统发育分析后分成2个亚组(Ⅰ和Ⅱ)。BoCBF蛋白的氨基酸长度为203~283 aa,全部是亲水性蛋白质。在结球甘蓝02-12中,BoCBF1、BoCBF2a和BoCBF3基因在叶、花、芽和角果中基本不表达,在愈伤组织、根和茎中表达量较低。转录组测序和实时荧光定量PCR分析发现,在耐寒结球甘蓝923和不耐寒结球甘蓝D9中,BoCBF2b、BoCBF2c基因不受低温诱导表达,BoCBF2a基因低温诱导表达最为迅速,其次是BoCBF1和BoCBF3基因。BoCBF1、BoCBF2a和BoCBF3基因的相对表达量在低温胁迫3~6 h达到最大值,相对表达量达到最大值后急剧下降,在24 h降至最低。本研究结果为后续开展BoCBF1、BoCBF2a和BoCBF3基因调控结球甘蓝响应低温胁迫机理研究奠定了基础。 展开更多
关键词 结球甘蓝 CBF基因家族 低温胁迫 基因表达
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路径式护理对卵巢癌术后患者胃肠功能恢复及预后的影响
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作者 卢淑兰 潘姝姝 +3 位作者 苏清青 余丽 郑建敏 罗红莲 《川北医学院学报》 2024年第1期127-131,共5页
目的:探讨路径式护理对卵巢癌术后患者胃肠功能恢复及预后的影响。方法:选取126例卵巢癌手术患者为研究对象,按照护理干预方式不同分为观察组和对照组,每组各63例。对照组患者予以手术常规护理干预;观察组患者在对照组基础上予以路径式... 目的:探讨路径式护理对卵巢癌术后患者胃肠功能恢复及预后的影响。方法:选取126例卵巢癌手术患者为研究对象,按照护理干预方式不同分为观察组和对照组,每组各63例。对照组患者予以手术常规护理干预;观察组患者在对照组基础上予以路径式护理干预,干预时间均为3个月。比较两组患者术后(胃肠功能恢复时间及住院时间、肠鸣音恢复、首次排便时间)、疲乏症状[癌症疲乏量表(CFS)]、心理状态[焦虑自评量表(SAS)及抑郁自评量表(SDS)评分]、生活质量[癌症生命质量核心量表(QLQ-C30)及卵巢癌患者生活质量问卷评分(QLQ-OV28)]。结果:干预后,观察组患者术后胃肠功能恢复时间及住院时间短于对照组(P<0.05);CFS各项评分、SAS及SDS评分、QLQ-OV28中消化道症状、外在形象和治疗依从性评分均低于对照组(P<0.05);QLQ-C30总分高于对照组(P<0.05)。结论:路径式护理可改善卵巢癌患者术后胃肠功能及心理状况,缓解癌性疲乏,改善患者生活质量。 展开更多
关键词 路径式护理 卵巢癌 胃肠功能 预后
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注重基础、立足工程、强化实践、融入模拟、激励创新——材料力学教学改革探索
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作者 李霄琳 周立明 +3 位作者 于莉 朱珊 彭帅英 张晓皖 《力学与实践》 2024年第1期179-187,共9页
材料力学是机械类、土木类和力学类等工科类专业的核心课程,课程秉承“强基础、重实践、融模拟、促创新”的理念;构建“融工程、融前沿、融思政”的教学资源与内容,夯实学生的力学理论知识,培养学生利用力学理论解决实际工程问题的能力... 材料力学是机械类、土木类和力学类等工科类专业的核心课程,课程秉承“强基础、重实践、融模拟、促创新”的理念;构建“融工程、融前沿、融思政”的教学资源与内容,夯实学生的力学理论知识,培养学生利用力学理论解决实际工程问题的能力,同时帮助学生塑造正确的世界观、人生观、价值观和职业观;将抽象的力学概念与三阶递进的课程实践融会贯通,培养学生的动手实践能力、探索精神和创新能力;将数值模拟技术引入课堂,初步培养学生利用数值模拟软件解决力学问题的能力。建立以传授知识为中心,以解决工程问题为导向,以创新实践为特点,以数值模拟软件为工具,以立德树人为根本的课堂。 展开更多
关键词 材料力学 教学改革 课程实践 数值模拟
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栝楼根腐病镰孢菌拮抗菌SJ1623发酵代谢物的抑制活性
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作者 余利 孟祥涛 +2 位作者 陈甦 潘怀松 段海明 《安徽农业科学》 CAS 2024年第3期119-121,共3页
检测了6株拮抗菌发酵上清液对栝楼根腐病菌的抑制活性,采用菌丝生长速率法测定优势拮抗菌不同接种量和发酵时间对发酵上清液抑菌活性的影响,测定了不同稀释倍数的发酵上清液和脂肽粗提物对栝楼根腐病菌的抑制活性。结果表明,对栝楼根腐... 检测了6株拮抗菌发酵上清液对栝楼根腐病菌的抑制活性,采用菌丝生长速率法测定优势拮抗菌不同接种量和发酵时间对发酵上清液抑菌活性的影响,测定了不同稀释倍数的发酵上清液和脂肽粗提物对栝楼根腐病菌的抑制活性。结果表明,对栝楼根腐病菌抑制活性最高的拮抗菌为SJ1623,种子液培养时间为10 h,0.75%(体积比)的接种量效果较好;发酵上清液稀释10倍对病菌的抑制率为87.6%,脂肽粗提物50倍稀释液对病菌的抑制率为83.1%。 展开更多
关键词 栝楼根腐病 拮抗菌 发酵液 抑制活性
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Directed Acyclic Graph Blockchain for Secure Spectrum Sharing and Energy Trading in Power IoT
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作者 Zixi Zhang Mingxia Zhang +2 位作者 yu li Bo Fan li Jiang 《China Communications》 SCIE CSCD 2023年第5期182-197,共16页
Peer-to-peer(P2P)spectrum sharing and energy trading are promising solutions to locally satisfy spectrum and energy demands in power Internet of Things(IoT).However,implementation of largescale P2P spectrum sharing an... Peer-to-peer(P2P)spectrum sharing and energy trading are promising solutions to locally satisfy spectrum and energy demands in power Internet of Things(IoT).However,implementation of largescale P2P spectrum sharing and energy trading confronts security and privacy challenges.In this paper,we exploit consortium blockchain and Directed Acyclic Graph(DAG)to propose a new secure and distributed spectrum sharing and energy trading framework in power IoT,named spectrum-energy chain,where a set of local aggregators(LAGs)cooperatively confirm the identity of the power devices by utilizing consortium blockchain,so as to form a main chain.Then,the local power devices verify spectrum and energy micro-transactions simultaneously but asynchronously to form local spectrum tangle and local energy tangle,respectively.Moreover,an iterative double auction based micro transactions scheme is designed to solve the spectrum and energy pricing and the amount of shared spectrum and energy among power devices.Security analysis and numerical results illustrate that the developed spectrum-energy chain and the designed iterative double auction based microtransactions scheme are secure and efficient for spectrum sharing and energy trading in power IoT. 展开更多
关键词 power Internet of Things(IoT) spectrum sharing energy trading security and privacy consortium blockchain Directed Acyclic Graph(DAG) iterative double auction
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Bioinspired urchin-like murray carbon nanostructure with protection shell for advanced lithium-sulfur batteries
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作者 Ya-Wen Tian Yong yu +9 位作者 liang Wu Min Yan Wen-Da Dong Chen-Yang Wang Hemdan S.H.Mohamed Zhao Deng li-Hua Chen Tawfique Hasan yu li Bao-lian Su 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期1-10,I0002,共11页
Commercial application of lithium-sulfur(Li-S) batteries is hindered by the insulating nature of sulfur and the dissolution of polysulfides. Here, a bioinspired 3D urchin-like N-doped Murray's carbon nanostructure... Commercial application of lithium-sulfur(Li-S) batteries is hindered by the insulating nature of sulfur and the dissolution of polysulfides. Here, a bioinspired 3D urchin-like N-doped Murray's carbon nanostructure(N-MCN) with interconnected micro-meso-macroporous structure and a polydopamine protection shell has been designed as an effective sulfur host for high-performance Li-S batteries. The advanced 3D hierarchically porous framework with the characteristics of the generalized Murray's law largely improves electrolyte diffusion, facilitates electrons/ions transfer and provides strong chemisorption for active species, leading to the synergistic structural and chemical confinement of polysulfides. As a result,the obtained P@S/N-MCN electrode with high areal sulfur loading demonstrates high capacity at high current densities after long cycles. This work reveals that following the generalized Murray's law is feasible to design high-performance sulfur cathode materials for potentially practical Li-S battery applications. 展开更多
关键词 Li-S batteries Murray’s law Hierarchically porous framework N-doped carbon Structural-chemical confinement
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From kesterite 2D nanosheets to wurtzite 1D nanorods:controllable synthesis of Cu-Zn-Sn-S and their application in electrocatalytic hydrogen evolution
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作者 yu li Shuaibing Wang +4 位作者 Jie Chen Ouyang lin Zhe Yin Chunhe Yang Aiwei Tang 《Journal of Semiconductors》 EI CAS CSCD 2023年第12期104-110,共7页
As typical quarternary copper-based chalcogenides,Cu–Zn–Sn–S nanocrystals(CZTS NCs)have emerged as a newfashioned electrocatalyst in hydrogen evolution reactions(HERs).Oleylamine(OM),a reducing surfactant and solve... As typical quarternary copper-based chalcogenides,Cu–Zn–Sn–S nanocrystals(CZTS NCs)have emerged as a newfashioned electrocatalyst in hydrogen evolution reactions(HERs).Oleylamine(OM),a reducing surfactant and solvent,plays a significant role in the assisting synthesis of CZTS NCs due to the ligand effect.Herein,we adopted a facile one-pot colloidal method for achieving the structure evolution of CZTS NCs from 2D nanosheets to 1D nanorods assisted through the continuous addition of OM.During the process,the mechanism of OM-induced morphology evolution was further discussed.When merely adding pure 1-dodecanethiol(DDT)as the solvent,the CZTS nanosheets were obtained.As OM was gradually added to the reaction,the CZTS NCs began to grow along the sides of the nanosheets and gradually shrink at the top,followed by the formation of stable nanorods.In acidic electrolytic conditions,the CZTS NCs with 1.0 OM addition display the optimal HER activity with a low overpotential of 561 m V at 10 m A/cm^(2) and a small Tafel slope of 157.6 m V/dec compared with other CZTS samples.The enhancement of HER activity could be attributed to the contribution of the synergistic effect of the diverse crystal facets to the reaction. 展开更多
关键词 2D nanosheets 1D nanorods structure evolution Cu-Zn-Sn-S electrocatalytic hydrogen evolution
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Engineering homotype heterojunctions in hard carbon to induce stable solid electrolyte interfaces for sodium-ion batteries
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作者 Chengxin yu yu li +6 位作者 Haixia Ren Ji Qian Shuo Wang Xin Feng Mingquan liu Ying Bai Chuan Wu 《Carbon Energy》 SCIE CAS CSCD 2023年第1期181-193,共13页
Developing effective strategies to improve the initial Coulombic efficiency(ICE)and cycling stability of hard carbon(HC)anodes for sodium-ion batteries is the key to promoting the commercial application of HC.In this ... Developing effective strategies to improve the initial Coulombic efficiency(ICE)and cycling stability of hard carbon(HC)anodes for sodium-ion batteries is the key to promoting the commercial application of HC.In this paper,homotype heterojunctions are designed on HC to induce the generation of stable solid electrolyte interfaces,which can effectively increase the ICE of HC from 64.7%to 81.1%.The results show that using a simple surface engineering strategy to construct a homotypic amorphous Al_(2)O_(3) layer on the HC could shield the active sites,and further inhibit electrolyte decomposition and side effects occurrence.Particularly,due to the suppression of continuous decomposition of NaPF 6 in ester-based electrolytes,the accumulation of NaF could be reduced,leading to the formation of thinner and denser solid electrolyte interface films and a decrease in the interface resistance.The HC anode can not only improve the ICE but elevate its sodium storage performance based on this homotype heterojunction composed of HC and Al_(2)O_(3).The optimized HC anode exhibits an outstanding reversible capacity of 321.5mAhg^(−1) at 50mAg^(−1).The cycling stability is also improved effectively,and the capacity retention rate is 86.9%after 2000 cycles at 1Ag^(−1) while that of the untreated HC is only 52.6%.More importantly,the improved sodium storage behaviors are explained by electrochemical kinetic analysis. 展开更多
关键词 hard carbon anodes homotype heterojunctions sodium-ion batteries solid electrolyte interface surface engineering
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Values of Donor Serum Lipids and Calcium in Predicting Graft Function after Kidney Transplantation:A Retrospective Study
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作者 Hui-bo SHI yuan-yuan ZHAO +12 位作者 yu li Yi li Bin liU Nian-qiao GONG Sheng CHANG Dun-feng DU Lan ZHU Jing XU Xiao-qin li Meng-jun ZENG Shang-xin DONG Zhi-shui CHEN Ji-pin JIANG 《Current Medical Science》 SCIE CAS 2023年第3期514-519,共6页
Objective Delayed graft function(DGF)and early graft loss of renal grafts are determined by the quality of the kidneys from the deceased donor.As“non-traditional”risk factors,serum biomarkers of donors,such as lipid... Objective Delayed graft function(DGF)and early graft loss of renal grafts are determined by the quality of the kidneys from the deceased donor.As“non-traditional”risk factors,serum biomarkers of donors,such as lipids and electrolytes,have drawn increasing attention due to their effects on the postoperative outcomes of renal grafts.This study aimed to examine the value of these serum biomarkers for prediction of renal graft function.Methods The present study consecutively collected 306 patients who underwent their first single kidney transplantation(KT)from adult deceased donors in our center from January 1,2018 to December 31,2019.The correlation between postoperative outcomes[DGF and abnormal serum creatinine(SCr)after 6 and 12 months]and risk factors of donors,including gender,age,body mass index(BMI),past histories,serum lipid biomarkers[cholesterol,triglyceride,high-density lipoprotein(HDL)and low-density lipoprotein(DL)],and serum electrolytes(calcium and sodium)were analyzed and evaluated.Results(1)Donor age and pre-existing hypertension were significantly correlated with the incidence rate of DGF and high SCr level(≥2 mg/dL)at 6 and 12 months after KT(P<0.05);(2)The donor’s BMI was significantly correlated with the incidence rate of DGF after KT(P<0.05);(3)For serum lipids,merely the low level of serum HDL of the donor was correlated with the reduced incidence rate of high SCr level at 12 months after KT[P<0.05,OR(95%CI):0.425(0.202–0.97)];(4)The serum calcium of the donor was associated with the reduced incidence rate of high SCr level at 6 and 12 months after KT[P<0.05,OR(95%CI):0.184(0.045–0.747)and P<0.05,OR(95%CI):0.114(0.014–0.948),respectively].Conclusion The serum HDL and calcium of the donor may serve as predictive factors for the postoperative outcomes of renal grafts after KT,in addition to the donor’s age,BMI and pre-existing hypertension. 展开更多
关键词 delayed graft function serum creatinine serum high-density lipoprotein serum calcium kidney transplantation
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Interface-Structure-Modulated CuF_(2)/CF_(x) Composites for High-Performance Lithium Primary Batteries
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作者 lidong Sun Cong Peng +2 位作者 lingchen Kong yu li Wei Feng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期120-128,共9页
Lithium primary batteries are widely used in various fields where high energy densities and long storage times are in demand.However,studies on lithium primary batteries are currently focused on the gravimetric energy... Lithium primary batteries are widely used in various fields where high energy densities and long storage times are in demand.However,studies on lithium primary batteries are currently focused on the gravimetric energy densities of active materials and rarely account for the volumetric energy requirements of unmanned devices.Herein,CuF_(2)/CF_(x) composites are prepared via planetary ball milling(PBM)to improve the volumetric energy densities of lithium primary batteries using the high mass density of CuF_(2),achieving a maximum volumetric energy density of 4163.40 Wh L^(-1).The CuF_(2)/CF_(x) hybrid cathodes exhibit three distinct discharge plateaus rather than simple combinations of the discharge curves of their components.This phenomenon is caused by charge redistribution and lattice modulation on the contact surfaces of CuF_(2) and CF_(x) during PBM,which change the valence state of Cu and modify the electronic structures of the composites.As a result,CuF_(2)/CF_(x) hybrid cathodes exhibit unique discharge behaviors and improved rate capabilities,delivering a maximum power density of 11.16 kW kg^(-1)(25.56 kW L^(-1)).Therefore,it is a promising strategy to further improve the comprehensive performance of lithium primary batteries through the use of interfacial optimization among different fluoride cathodes. 展开更多
关键词 CF_(x) Cu^(3+) CuF_(2) primary battery volumetric energy density
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Red light induces salicylic acid accumulation by activating CaHY5 to enhance pepper resistance against Phytophthora capsici
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作者 Youxin Yang yu li +8 位作者 Yelan Guang Jinhui lin Yong Zhou Ting yu Fei Ding Yanfeng Wang Jinyin Chen Yanhong Zhou Fengfeng Dang 《Horticulture Research》 SCIE CSCD 2023年第11期240-252,共13页
Pepper(Capsicum annuum L.)is frequently challenged by various pathogens,among which Phytophthora capsici is the most devastating to pepper production.Red light signal acts as a positive induction of plant resistance a... Pepper(Capsicum annuum L.)is frequently challenged by various pathogens,among which Phytophthora capsici is the most devastating to pepper production.Red light signal acts as a positive induction of plant resistance against multiple pathogens.However,little is known about how the red light signal affects pepper resistance to P.capsici infection(PCI).Here,we report that red light regulates salicylic acid(SA)accumulation by activating elongated hypocotyl5(CaHY5),a basic leucine zipper(bZIP)transcription factor,thereby decreasing pepper susceptibility to PCI.Exogenous SA treatment reduced pepper susceptibility to PCI,while silencing of CaPHYB(a red light photoreceptor)increased its susceptibility.PCI significantly induced CaHY5 expression,and silencing of CaHY5 reduced SA accumulation,accompanied by decreases in the expression levels of phenylalanine ammonia-lyase 3(CaPAL3),CaPAL7,pathogenesis-related 1(CaPR1),and CaPR1L,which finally resulted in higher susceptibility of pepper to PCI.Moreover,CaHY5 was found to activate the expression of CaPAL3 and CaPAL7,which are essential for SA biosynthesis,by directly binding to their promoters.Further analysis revealed that exogenous SA treatment could restore the resistance of CaHY5-silenced pepper plants to PCI.Collectively,this study reveals a critical mechanism through which red light induces SA accumulation by regulating CaHY5-mediated CaPAL3 and CaPAL7 expression,leading to enhanced resistance to PCI.Moreover,red light-induced CaHY5 regulates pepper resistance to PCI,which may have implications for PCI control in protected vegetable production. 展开更多
关键词 PEPPER RESISTANCE light
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