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TP347H与Super304H耐热钢热疲劳过程的变形与开裂行为研究
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作者 李炳辰 李健 +4 位作者 高淼淼 刘晨 曹铁山 程从前 赵杰 《热加工工艺》 北大核心 2024年第17期73-77,83,共6页
基于金属板材热疲劳试验方法(HB 6660-2011),对比分析了TP347H和Super304H两种耐热钢的供货态、相同热处理条件下的固溶态和时效态试样在热疲劳过程中底部尺寸的变形行为,以及缺口部位裂纹形貌。结果表明:这3种状态Super304H钢在热疲劳... 基于金属板材热疲劳试验方法(HB 6660-2011),对比分析了TP347H和Super304H两种耐热钢的供货态、相同热处理条件下的固溶态和时效态试样在热疲劳过程中底部尺寸的变形行为,以及缺口部位裂纹形貌。结果表明:这3种状态Super304H钢在热疲劳试验后的变形均小于相应TP347H钢的,TP347H缺口呈现相对较大的钝化,时效态试样钝化最大,裂纹最短。缺口附近的观察结果,TP347H在缺口附近龟裂损伤程度弱于Super304H钢的,开裂方式主要为沿晶开裂,也有部分穿晶开裂。 展开更多
关键词 TP347H super304H 热疲劳 变形 开裂
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New direction for surgery:Super minimally invasive surgery 被引量:2
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作者 En-Qiang Linghu 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1676-1679,共4页
The top goal of modern medicine is treating disease without destroying organ structures and making patients as healthy as they were before their sickness.Minimally invasive surgery(MIS)has dominated the surgical realm... The top goal of modern medicine is treating disease without destroying organ structures and making patients as healthy as they were before their sickness.Minimally invasive surgery(MIS)has dominated the surgical realm because of its lesser invasiveness.However,changes in anatomical structures of the body and reconstruction of internal organs or different organs are common after traditional surgery or MIS,decreasing the quality of life of patients post-operation.Thus,I propose a new treatment mode,super MIS(SMIS),which is defined as“curing a disease or lesion which used to be treated by MIS while preserving the integrity of the organs”.In this study,I describe the origin,definition,operative channels,advantages,and future perspectives of SMIS. 展开更多
关键词 super minimally invasive surgery Minimally invasive surgery Treatment mode Traditional Surgery New direction for surgery
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Hollow Ni Mo-based nitride heterojunction with super-hydrophilic/aerophobic surface for efficient urea-assisted hydrogen production 被引量:1
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作者 Yuying Fan Ying Gu +3 位作者 Dongxu Wang Yanqing Jiao Aiping Wu Chungui Tian 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期428-439,I0009,共13页
Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/device.The design of catalysts with a super-hydrophilic/aerophobic structure and optim... Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/device.The design of catalysts with a super-hydrophilic/aerophobic structure and optimized electron distribution holds great promise.Here,we have designed a threedimensional(3D)hollow Ni/NiMoN hierarchical structure with arrayed-sheet surface based on a onepot hydrothermal route for efficient urea-assisted HER based on a simple hydrothermal process.The Ni/NiMoN catalyst exhibits super-hydrophilic/aerophobic properties with a small droplet contact angle of 6.07°and an underwater bubble contact angle of 155.7°,thus facilitating an escape of bubbles from the electrodes.Density functional theory calculations and X-ray photoelectron spectroscopy results indicate the optimized electronic structure at the interface of Ni and NiMoN,which can promote the adsorption/desorption of reactants and intermediates.The virtues combining with a large specific surface area endow Ni/NiMoN with efficient catalytic activity of low potentials of 25 mV for HER and 1.33 V for UOR at10 mA cm^(-2).The coupled HER and UOR system demonstrates a low cell voltage of 1.42 V at 10 mA cm^(-2),which is approximately 209 mV lower than water electrolysis. 展开更多
关键词 Hydrogen evolution Transition metal nitrides Hollow heterojunctions Urea electrooxidation super hydrophilic/aerophobic
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Image super‐resolution via dynamic network 被引量:1
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作者 Chunwei Tian Xuanyu Zhang +2 位作者 Qi Zhang Mingming Yang Zhaojie Ju 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期837-849,共13页
Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely exp... Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely express predicted high‐quality images for complex scenes.A dynamic network for image super‐resolution(DSRNet)is presented,which contains a residual enhancement block,wide enhancement block,feature refine-ment block and construction block.The residual enhancement block is composed of a residual enhanced architecture to facilitate hierarchical features for image super‐resolution.To enhance robustness of obtained super‐resolution model for complex scenes,a wide enhancement block achieves a dynamic architecture to learn more robust information to enhance applicability of an obtained super‐resolution model for varying scenes.To prevent interference of components in a wide enhancement block,a refine-ment block utilises a stacked architecture to accurately learn obtained features.Also,a residual learning operation is embedded in the refinement block to prevent long‐term dependency problem.Finally,a construction block is responsible for reconstructing high‐quality images.Designed heterogeneous architecture can not only facilitate richer structural information,but also be lightweight,which is suitable for mobile digital devices.Experimental results show that our method is more competitive in terms of performance,recovering time of image super‐resolution and complexity.The code of DSRNet can be obtained at https://github.com/hellloxiaotian/DSRNet. 展开更多
关键词 CNN dynamic network image super‐resolution lightweight network
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Priming mesenchymal stem cells to develop “super stem cells” 被引量:1
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作者 Khawaja Husnain Haider 《World Journal of Stem Cells》 SCIE 2024年第6期623-640,共18页
The stem cell pre-treatment approaches at cellular and sub-cellular levels encompass physical manipulation of stem cells to growth factor treatment,genetic manipulation,and chemical and pharmacological treatment,each ... The stem cell pre-treatment approaches at cellular and sub-cellular levels encompass physical manipulation of stem cells to growth factor treatment,genetic manipulation,and chemical and pharmacological treatment,each strategy having advantages and limitations.Most of these pre-treatment protocols are non-combinative.This editorial is a continuum of Li et al’s published article and Wan et al’s editorial focusing on the significance of pre-treatment strategies to enhance their stemness,immunoregulatory,and immunosuppressive properties.They have elaborated on the intricacies of the combinative pre-treatment protocol using pro-inflammatory cytokines and hypoxia.Applying a well-defined multi-pronged combinatorial strategy of mesenchymal stem cells(MSCs),pre-treatment based on the mechanistic understanding is expected to develop“Super MSCs”,which will create a transformative shift in MSC-based therapies in clinical settings,potentially revolutionizing the field.Once optimized,the standardized protocols may be used with slight modifications to pre-treat different stem cells to develop“super stem cells”with augmented stemness,functionality,and reparability for diverse clinical applications with better outcomes. 展开更多
关键词 Cell survival Cell therapy PRECONDITIONING Pre-treatment Stem cells super stem cells
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Connotation,pathway and significance of carbon neutrality“super energy system”:A case study of the Ordos Basin,NW China
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作者 ZOU Caineng LI Shixiang +12 位作者 XIONG Bo CHEN Yanpeng ZHANG Guosheng XIE Xiaoping LIU Hanlin MA Feng LIANG Yingbo ZHU Kai GUAN Chunxiao PAN Songqi HOU Meifang YUAN Yilin LUO Shuanghan 《Petroleum Exploration and Development》 SCIE 2024年第4期1066-1082,共17页
Super oil and gas basins provide the energy foundation for social progress and human development.In the context of climate change and carbon peak and carbon neutrality goals,constructing an integrated energy and carbo... Super oil and gas basins provide the energy foundation for social progress and human development.In the context of climate change and carbon peak and carbon neutrality goals,constructing an integrated energy and carbon neutrality system that balances energy production and carbon reduction becomes crucial for the transformation of such basins.Under the framework of a green and intelligent energy system primarily based on“four news”,new energy,new electricity,new energy storage,and new intelligence,integrating a“super energy system”composed of a huge amount of underground resources of coal,oil,gas and heat highly overlapping with abundant wind and solar energy resources above ground,and a regional intelligent energy consumption system with coordinated development and utilization of fossil energy and new energy,with a carbon neutrality system centered around carbon cycling is essential.This paper aims to select the traditional oil and gas basins as“super energy basins”with the conditions to build world-class energy production and demonstration bases for carbon neutrality.The Ordos Basin has unique regional advantages,including abundant fossil fuel and new energy resources,as well as matching CO_(2)sources and sinks,position it as a carbon neutrality“super energy basin”which explores the path of transformation of traditional oil and gas basins.Under the integrated development concept and mode of“coal+oil+gas+new energy+carbon capture,utilization and storage(CCUS)/carbon capture and storage(CCS)”,the carbon neutrality in super energy basin is basically achieved,which enhance energy supply and contribute to the carbon peak and carbon neutrality goals,establish a modern energy industry and promote regional green and sustainable development.The pioneering construction of the world-class carbon neutrality“super energy system”demonstration basin in China represented by the Ordos Basin will reshape the new concept and new mode of exploration and development of super energy basins,which is of great significance to the global energy revolution under carbon neutrality. 展开更多
关键词 super energy system carbon neutrality system carbon neutrality super energy system carbon neutrality super energy basin Ordos Basin
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Deep eutectic solvents:Green multi-task agents for sustainable super green hydrogen technologies
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作者 Raiyan Al-Farsi Maan Hayyan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期357-382,共26页
While reliance on renewable energy resources has become a reality, there is still a need to deploy greener and more sustainable methods in order to achieve sustainable development goals. Indeed, green hydrogen is curr... While reliance on renewable energy resources has become a reality, there is still a need to deploy greener and more sustainable methods in order to achieve sustainable development goals. Indeed, green hydrogen is currently believed to be a reliable solution for global warming and the pollution challenges arising from fossil fuels, making it the resilient fuel of the future. However, the sustainability of green hydrogen technologies is yet to be achieved. In this context, generation of green hydrogen with the aid of deep eutectic solvents(DESs) as green mixtures has been demonstrated as a promising research area. This systematic review article covers green hydrogen generation through water splitting and biomass fermentation when DESs are utilized within the generation process. It also discusses the incorporation of DESs in fuel cell technologies. DESs can play a variety of roles such as solvent, electrolyte, or precursor;colloidal suspension and reaction medium;galvanic replacement, shape-controlling, decoration, or extractive agent;finally oxidant. These roles are relevant to several methods of green hydrogen generation, including electrocatalysis, photocatalysis, and fermentation. As such, it is of utmost importance to screen potential DES formulations and determine how they can function in and contribute throughout the green hydrogen mobility stages. The realization of super green hydrogen generation stands out as a pivotal milestone in our journey towards achieving a more sustainable form of development;DESs have great potential in making this milestone achievable. Overall, incorporating DESs in hydrogen generation constitutes a promising research area and offers potential scalability for green hydrogen production, storage,transport, and utilization. 展开更多
关键词 Watersplitting BIOHYDROGEN super green hydrogen ELECTROCATALYSIS PHOTOCATALYSIS Fuel cell Power-to-X
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Trend of Storm Surge Induced by Typical Landfall Super Typhoons During 1975–2021 in the Eastern China Sea
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作者 LUO Feng WANG Yi +3 位作者 TAO Aifeng SHI Jian WANG Yongzhi ZHANG Chi 《Journal of Ocean University of China》 CAS CSCD 2024年第2期277-286,共10页
Climate change affects the activity of global and regional tropical cyclones(TCs).Among all TCs,typical super typhoons(STYs)are particularly devastating because they maintain their intensity when landing on the coast ... Climate change affects the activity of global and regional tropical cyclones(TCs).Among all TCs,typical super typhoons(STYs)are particularly devastating because they maintain their intensity when landing on the coast and thus cause casualties,economic losses,and environmental damage.Using a 3D tidal model,we reconstructed the typhoon(TY)wind field to simulate the storm surge induced by typical STYs.The TY activity was then analyzed using historical data.Results showed a downtrend of varying degrees in the annual frequency of STYs and TCs in the Western North Pacific(WNP)Basin,with a significant trend change observed for TCs from 1949 to 2021.A large difference in the interannual change in frequency was found between STYs and TCs in the WNP and Eastern China Sea(ECS).Along the coast of EC,the frequency of landfall TCs showed a weak downtrend,and the typical STYs showed reverse micro growth with peak activity in August.Zhejiang,Fujian,and Taiwan were highly vulnerable to the frontal hits of typical STYs.Affected by climate change,the average lifetime maximum intensity(LMI)locations and landfall locations of typical STYs in the ECS basin showed a significant poleward migration trend.In addition,the annual average LMI and accumulated cyclone energy showed an uptrend,indicating the increasing severity of the disaster risk.Affected by the typical STY activity in the ECS,the maximum storm surge area also showed poleward migration,and the coast of North China faced potential growth in high storm surge risks. 展开更多
关键词 storm surge super typhoons tropical cyclones eastern China Sea poleward migration
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Preparation and Swelling Kinetic Analysis of Poly (HPMC-co-AA-co-AM) Super Absorbent Resin
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作者 马砺 WANG Xin +2 位作者 LIU Xixi WEI Gaoming GUO Ying 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期790-799,共10页
Super absorbent resin(SAR)is prepared by aqueous high temperature polymerization using hydroxypropyl methylcellulose(HPMC)as monomer backbone material,acrylic acid(AA)and acrylamide(AM)as the graft copolymer monomer,p... Super absorbent resin(SAR)is prepared by aqueous high temperature polymerization using hydroxypropyl methylcellulose(HPMC)as monomer backbone material,acrylic acid(AA)and acrylamide(AM)as the graft copolymer monomer,potassium persulfate(KPS)as the initiator to generate free radicals,and N,N`-methylenebisacrylamide(MBA)as cross-linking agent for cross-linking reaction.Simutaneously,the influence of individual factors on the water absorption is investigated,and these factors are mainly AA,AM,KPS,MBA,HPMC,and reaction temperature.The optimized conditions are obtained by the experiment repeating for several times.The water absorption multiplicity and salt absorption multiplicity under the conditions are 782.4 and 132.5 g/g,respectivity.Furthermore,the effects of different temperatures and salt concentrations on its water absorption,as well as the swelling kinetics of SAR are studied.It is indicated the water-absorbing swelling process is mainly caused by the difference in water osmotic pressure and Na+concentration inside and outside the cross-linked molecular structure of the resin,which is not only consistent with the quasi-secondary kinetic model,but also with the Fick diffusion model. 展开更多
关键词 super absorbent resin swelling kinetics water absorption graft copolymerization hydroxypropyl methyl cellulose
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Prediction of Hot Deformation Behavior of 7Mo Super Austenitic Stainless Steel Based on Back Propagation Neural Network
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作者 WANG Fan WANG Xitao +1 位作者 XU Shiguang HE Jinshan 《材料导报》 EI CAS CSCD 北大核心 2024年第17期165-171,共7页
The hot compression tests of 7Mo super austenitic stainless(SASS)were conducted to obtain flow curves at the temperature of 1000-1200℃and strain rate of 0.001 s^(-1)to 1 s^(-1).To predict the non-linear hot deformati... The hot compression tests of 7Mo super austenitic stainless(SASS)were conducted to obtain flow curves at the temperature of 1000-1200℃and strain rate of 0.001 s^(-1)to 1 s^(-1).To predict the non-linear hot deformation behaviors of the steel,back propagation-artificial neural network(BP-ANN)with 16×8×8 hidden layer neurons was proposed.The predictability of the ANN model is evaluated according to the distribution of mean absolute error(MAE)and relative error.The relative error of 85%data for the BP-ANN model is among±5%while only 42.5%data predicted by the Arrhenius constitutive equation is in this range.Especially,at high strain rate and low temperature,the MAE of the ANN model is 2.49%,which has decreases for 18.78%,compared with conventional Arrhenius constitutive equation. 展开更多
关键词 7Mo super austenitic stainless steel hot deformation behavior flow stress BP-ANN Arrhenius constitutive equation
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A Unified Model Fusing Region of Interest Detection and Super Resolution for Video Compression
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作者 Xinkun Tang Feng Ouyang +2 位作者 Ying Xu Ligu Zhu Bo Peng 《Computers, Materials & Continua》 SCIE EI 2024年第6期3955-3975,共21页
High-resolution video transmission requires a substantial amount of bandwidth.In this paper,we present a novel video processing methodology that innovatively integrates region of interest(ROI)identification and super-... High-resolution video transmission requires a substantial amount of bandwidth.In this paper,we present a novel video processing methodology that innovatively integrates region of interest(ROI)identification and super-resolution enhancement.Our method commences with the accurate detection of ROIs within video sequences,followed by the application of advanced super-resolution techniques to these areas,thereby preserving visual quality while economizing on data transmission.To validate and benchmark our approach,we have curated a new gaming dataset tailored to evaluate the effectiveness of ROI-based super-resolution in practical applications.The proposed model architecture leverages the transformer network framework,guided by a carefully designed multi-task loss function,which facilitates concurrent learning and execution of both ROI identification and resolution enhancement tasks.This unified deep learning model exhibits remarkable performance in achieving super-resolution on our custom dataset.The implications of this research extend to optimizing low-bitrate video streaming scenarios.By selectively enhancing the resolution of critical regions in videos,our solution enables high-quality video delivery under constrained bandwidth conditions.Empirical results demonstrate a 15%reduction in transmission bandwidth compared to traditional super-resolution based compression methods,without any perceivable decline in visual quality.This work thus contributes to the advancement of video compression and enhancement technologies,offering an effective strategy for improving digital media delivery efficiency and user experience,especially in bandwidth-limited environments.The innovative integration of ROI identification and super-resolution presents promising avenues for future research and development in adaptive and intelligent video communication systems. 展开更多
关键词 super resolution region of interest detection video compression
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跨境电商“产教融合”SUPER模式的构建与实践
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作者 周栋涎 《中国科技期刊数据库 科研》 2024年第6期0088-0091,共4页
近年来,我国的跨境电商行业发展迅猛,人才缺口巨大,培养出相当数量的优秀跨境电商人才成为政府、高校、行业和企业急需探讨和解决的问题。本文通过调研高校跨境电商专业“产教融合”痛点,结合校企合作相关工作经验,提出了“产教融合”SU... 近年来,我国的跨境电商行业发展迅猛,人才缺口巨大,培养出相当数量的优秀跨境电商人才成为政府、高校、行业和企业急需探讨和解决的问题。本文通过调研高校跨境电商专业“产教融合”痛点,结合校企合作相关工作经验,提出了“产教融合”SUPER模式,从学生(S)、高校(U)、项目(P)、企业(E)和R(结果)五个方面的“产教融合”联合培养模式,助力跨境电商人才培养。并且在项目SUPER模式的校企合作实践中,笔者发现该模式在人才培养中能发挥较显著的作用,应用SUPER模式的项目实践比以往的校企合作项目效益好,学生、企业、高校等实现多方共赢。当然,本研究也存在样本不大、操作平台不够丰富等较多不足,希望能抛砖引玉,为跨境电商人才培养提供一点思路,也希望获得更多同行的指导。 展开更多
关键词 跨境电商 产教融合 super模式 高校
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双缸进化器:2024 KTM 1390 Super Duke R
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作者 董澄 《摩托车》 2024年第7期44-51,共8页
在顶级的街车阵列,KTM的超级公爵1290 Super Duke绝对占有一席之地。掌控132kW最大功率,挥洒140N·m最大扭矩,驱动只有约200kg的重量,再得到优秀悬挂系统和先进电控系统的加持,驾驶这匹超级猛兽跑在公路上,简直如入无人之境!
关键词 最大扭矩 悬挂系统 最大功率 KTM 电控系统 super
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Numerical Simulation of Super-Resolution Structured Illumination Microscopy (SIM) Using Heintzmann-Cremer Algorithm with Non-Continuous Spatial Frequency Support
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作者 Mesfin Woldeyohannes William McCray Weiguo Yang 《Optics and Photonics Journal》 2024年第5期75-90,共16页
We report a comprehensive numerical study of super resolution (SR) structured illumination microscopy (SIM) utilizing the classic Heintzmann-Cremer SIM process and algorithm. In particular, we investigated the impact ... We report a comprehensive numerical study of super resolution (SR) structured illumination microscopy (SIM) utilizing the classic Heintzmann-Cremer SIM process and algorithm. In particular, we investigated the impact of the diffraction limit of the underlying imaging system on the optimal SIM grating frequency that can be used to obtain the highest SR enhancement with non-continuous spatial frequency support. Besides confirming the previous theoretical and experimental work that SR-SIM can achieve an enhancement close to 3 times the diffraction limit with grating pattern illuminations, we also observe and report a series of more subtle effects of SR-SIM with non-continuous spatial frequency support. Our simulations show that when the SIM grating frequency exceeds twice that of the diffraction limit, the higher SIM grating frequency can help achieve a higher SR enhancement for the underlying imaging systems whose diffraction limit is low, though this enhancement is obtained at the cost of losing resolution at some lower resolution targets. Our simulations also show that, for underlying imaging systems with high diffraction limits, however, SR-SIM grating frequencies above twice the diffraction limits tend to bring no significant extra enhancement. Furthermore, we observed that there exists a limit grating frequency above which the SR enhancement effect is lost, and the reconstructed images essentially have the same resolution as the one obtained directly from the underlying imaging system without using the SIM process. 展开更多
关键词 Structured Illumination Microscopy super Resolution Imaging Spatial Frequency Support Diffraction Limit
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时效粗、细晶Super304H钢的第二相析出行为及力学性能 被引量:2
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作者 占先强 汤文明 +4 位作者 刘俊建 王万里 张建华 吴跃 王严 《材料热处理学报》 CAS CSCD 北大核心 2023年第5期152-161,共10页
采用预变形后固溶处理的方法制备了粗晶Super304H钢试样,对比研究了粗、细晶Super304H钢试样在700℃时效过程中的第二相析出行为及力学性能。结果表明:时效过程中,细小MX相与富Cu相颗粒主要分布于奥氏体晶内,奥氏体晶粒尺寸对其析出行... 采用预变形后固溶处理的方法制备了粗晶Super304H钢试样,对比研究了粗、细晶Super304H钢试样在700℃时效过程中的第二相析出行为及力学性能。结果表明:时效过程中,细小MX相与富Cu相颗粒主要分布于奥氏体晶内,奥氏体晶粒尺寸对其析出行为影响不大。粗晶Super304H钢中的M23C6相颗粒择优沿奥氏体晶界析出,长大速率大,时效1200 h后,呈连续网络状分布。随着时效时间的延长,粗、细晶Super304H钢试样的室温及高温拉伸强度先上升后下降,最终趋于稳定,断后伸长率单调下降。时效态粗晶Super304H钢试样的室温、高温拉伸力学性能,尤其是塑性,均明显小于时效态细晶Super304H钢试样。 展开更多
关键词 super304H奥氏体耐热钢 晶粒尺寸 时效 第二相析出 力学性能
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基于Super Learner集成学习模型对脑卒中的预测研究 被引量:1
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作者 孙浩浩 章剑林 +1 位作者 张子蓥 黄可欣 《杭州师范大学学报(自然科学版)》 CAS 2023年第6期590-597,610,共9页
使用索马里医院提供的脑卒中患者数据集,通过四分位距(interquartile range, IQR)方法和合成少数类过采样技术(synthetic minority oversampling technique, SMOTE)算法进行数据预处理,采用特征工程中的嵌入式方法对数据集进行特征分析... 使用索马里医院提供的脑卒中患者数据集,通过四分位距(interquartile range, IQR)方法和合成少数类过采样技术(synthetic minority oversampling technique, SMOTE)算法进行数据预处理,采用特征工程中的嵌入式方法对数据集进行特征分析,确定脑卒中诱发因素.以随机森林(random forest, RF)、极端梯度提升(extreme gradient boosting, XGB)和自适应提升(adaptive boosting, AdB)算法为第一层,高斯朴素贝叶斯(Gaussian naive bayes, GaNB)和支持向量机(support vector machine, SVM)为第二层,逻辑回归(logistic regression, LR)为元学习器构建超级学习者(super learner, SL)集成学习模型.仿真实验结果表明,相较于6种基础算法,SL模型预测效果最优,可为脑卒中的预测分析提供新的选择. 展开更多
关键词 脑卒中 特征分析 super learner 机器学习 预测
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基于Super C Band的可调增益掺铒光纤放大器设计 被引量:1
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作者 孟玉锦 程雯 《光通信研究》 2023年第5期73-78,共6页
随着网络业务流量的增长,通信业务对密集波分复用(DWDM)的性能要求越来越高。为了提高传输效率,传输频谱逐渐向C+L Band传输扩展,Super C Band传输应运而生,但目前与之对应的掺铒光纤放大器(EDFA)相关研究较少。针对这一问题,文章提出... 随着网络业务流量的增长,通信业务对密集波分复用(DWDM)的性能要求越来越高。为了提高传输效率,传输频谱逐渐向C+L Band传输扩展,Super C Band传输应运而生,但目前与之对应的掺铒光纤放大器(EDFA)相关研究较少。针对这一问题,文章提出了一种针对Super C Band传输的EDFA结构,基于Giles模型,分析了EDFA在Super C Band的特性,利用多级泵浦机制,设计了一种可以在Super C Band范围内进行放大的EDFA。结果表明,在-9.3 dBm入光时,该EDFA可以实现26 dB的平坦增益,16.7 dBm的输出功率,此时噪声指数小于5 dB,Ripple小于0.1 dB。并且根据需要,在入光处于-15.0~-3.5 dBm范围内时,通过调节泵浦功率与可调衰减器,均能够实现7~26 dB的可调增益。该EDFA可应用于5G传输和数据中心之间光纤通信等场合。 展开更多
关键词 掺铒光纤放大器 super C Band 光纤通信 数据中心互联
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Atmospheric and oceanic responses to Super Typhoon Mangkhut in the South China Sea:a coupled CROCO-WRF simulation 被引量:1
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作者 Mingyu LI Yijun HE Guoqiang LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1369-1388,共20页
The South China Sea(SCS)is the largest marginal sea in the Northwest Pacific Ocean,and it encounters frequent typhoons.The atmosphere and ocean will create significant thermal and dynamic responses during the intense ... The South China Sea(SCS)is the largest marginal sea in the Northwest Pacific Ocean,and it encounters frequent typhoons.The atmosphere and ocean will create significant thermal and dynamic responses during the intense disturbance caused by typhoons.However,these responses have not been thoroughly investigated owing to the complicated marine environment.According to the satellite data,the SCS Basin was observed to have a strong sea surface temperature(SST)response to Typhoon Mangkhut,resulting in widespread SST cooling.A coupled model was used to investigate the atmospheric and oceanic responses to Typhoon Mangkhut.Best-track data,satellite SST,and ARGO measurements show that the coupled WRF-CROCO simulation displays better track,intensity,SST,temperature,and salinity profiles than those of the WRF-only simulation.Results show that the typhoon induced rightward intensifications in wind speed,ocean current,and SST.The following are some remarkable atmosphere and ocean responses:(1)the SST below the inner-core region is cooled by 1℃,resulting in a 37%-44%decrease in wet enthalpy,and the central pressure is increased by~9 hPa.Therefore,the changes in SST below the innercore region of the SCS Basin have a significant impact on air-sea fluxes under high-wind conditions;(2)the ocean boundary layer analysis shows that near-inertial oscillations on the right side of the typhoon track and a strong inertial current up to~2.28 m/s in the upper ocean were observed,which resonated with the local wind and flow field on the right side and induced strong SST cooling;(3)a decrease in SST decreased the moist static energy of the typhoon boundary layer,thereby weakening the typhoon’s intensity.The difference in equivalent potential temperature and sea surface pressure have a good correlation,indicating that the influence of moist static energy on typhoon intensity cannot be overlooked. 展开更多
关键词 super Typhoon Mangkhut coupled ocean-atmosphere model wet enthalpy inertial current
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Super 304H钢在模拟烟气腐蚀环境中持久性能与组织演变研究
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作者 杨啸峰 徐雅欣 +2 位作者 鲁金涛 黄锦阳 李文亚 《热力发电》 CAS CSCD 北大核心 2023年第10期31-38,共8页
奥氏体钢在锅炉关键部位服役过程中面临烟气/煤灰腐蚀+应力协同作用的挑战,存在一定的安全隐患。在静态空气及烟气/煤灰腐蚀环境下,通过模拟实验台对Super 304H钢进行温度为650℃、应力为200~300 MPa的持久实验,研究腐蚀环境对其持久性... 奥氏体钢在锅炉关键部位服役过程中面临烟气/煤灰腐蚀+应力协同作用的挑战,存在一定的安全隐患。在静态空气及烟气/煤灰腐蚀环境下,通过模拟实验台对Super 304H钢进行温度为650℃、应力为200~300 MPa的持久实验,研究腐蚀环境对其持久性能及组织演变的影响。结果表明:相较于空气环境,腐蚀条件下Super 304H钢持久寿命下降幅度可达83%,且随着持久应力的降低合金寿命下降更明显;烟气/煤灰腐蚀导致合金表面连续的腐蚀产物出现开裂、剥落,基体发生内硫化,在拉应力的共同作用下试样内部出现沿晶开裂等蠕变损伤;基体表面由于合金元素的损失,在高温下发生再结晶,并在实验结束后发生马氏体转变,腐蚀-应力环境中合金表面腐蚀产物的开裂、剥落,内硫化物的形成,表层再结晶细晶区的增厚和晶界损伤的加剧共同促进了Super 304H钢的持久断裂。烟气/煤灰腐蚀环境通过影响Super 304H钢腐蚀过程,恶化合金基体组织影响其持久性能。 展开更多
关键词 super 304H钢 模拟烟气/煤灰腐蚀 持久性能 组织演变
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T92/Super304H异种钢焊接接头服役前后力学变化及其寿命评估 被引量:1
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作者 王国庆 马行驰 +3 位作者 解瑞雯 袁斌霞 潘卫国 沈利 《科学技术与工程》 北大核心 2023年第12期5005-5012,共8页
火电机组中过热器,再热器等部件需应用到异种钢焊接接头来满足不同环境的需求,这要求材料具有更高的耐高温腐蚀性能、屈服极限以及抗拉强度,而服役造成的老化会很大程度影响焊接件的性能,进而影响其寿命。为了研究服役对于异种钢焊接接... 火电机组中过热器,再热器等部件需应用到异种钢焊接接头来满足不同环境的需求,这要求材料具有更高的耐高温腐蚀性能、屈服极限以及抗拉强度,而服役造成的老化会很大程度影响焊接件的性能,进而影响其寿命。为了研究服役对于异种钢焊接接头T92/Super304H的力学性能的影响。通过在610℃高温状态下,对已服役和未服役的焊接接头进行了不同加载速率的拉伸试验,获得了应力应变曲线及拟合曲线,通过扫描电子显微镜(SEM)分析了断口形貌。在相同温度下,对试样加载不同应力进行蠕变试验,获得了焊接接头的本构方程和蠕变寿命预测模型,分析了其断裂原因。结果表明:已服役和未服役的焊接接头高温拉伸时断裂均发生在T92侧(T92热影响区),试样有明显的颈缩;材料的初始应力值越大,蠕变寿命越短;随着初始应力水平的增加,蠕变应变速率变化加快;寿命预测拟合曲线和实际的蠕变试验一致。 展开更多
关键词 T92/super304H焊接接头 服役 高温拉伸 蠕变 断口
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