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造境阅读推广活动:美国图书馆“Passive Program”的中文译名
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作者 王波 《大学图书情报学刊》 2026年第2期3-8,共6页
文章探讨了美国图书馆“Passive Program”的中文翻译问题。针对范并思教授的提问,文章指出将“Passive Program”译为“被动活动”不适合中文语境,因其带有消极色彩且未能准确反映这类活动所具有的图书馆员前期主动策划、过程中低干预... 文章探讨了美国图书馆“Passive Program”的中文翻译问题。针对范并思教授的提问,文章指出将“Passive Program”译为“被动活动”不适合中文语境,因其带有消极色彩且未能准确反映这类活动所具有的图书馆员前期主动策划、过程中低干预的核心特征。在分析得出“Passive Program”依靠空间与道具引导读者自发参与的特点后,作者提出将其转译为“造境阅读推广活动”,意指图书馆通过营造特定场景、情景或意境,激发读者自主阅读。“造境阅读推广活动”这个译名既契合“Passive Program”的内涵,又统摄了中美图书馆的同类实践,为理论研究、实践应用与中外交流提供了恰当的概念工具。 展开更多
关键词 Passive program 被动活动 造境阅读推广活动 场景阅读推广活动 情景阅读推广活动 意境阅读推广活动 美国图书馆
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下一代智算中心RDMA QP通信机制
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作者 王军良 林宝洪 +2 位作者 张娇 孙梦宇 潘永琛 《计算机工程与科学》 北大核心 2026年第2期228-237,共10页
当前智算中心主要采用远程直接存取RDMA协议实现集群内部的超高性能通信,每对进程之间都需要建立基于可靠连接RC类型的队列对QP。在下一代大规模智算中心的AI大模型场景下,All-to-All和All Reduce这些分布式的集合通信操作会触发进程与... 当前智算中心主要采用远程直接存取RDMA协议实现集群内部的超高性能通信,每对进程之间都需要建立基于可靠连接RC类型的队列对QP。在下一代大规模智算中心的AI大模型场景下,All-to-All和All Reduce这些分布式的集合通信操作会触发进程与进程间的全连接通信,基于RC的机制所需要维护的QP数量将突破百万,对RDMA网卡中有限的内存和性能带来极大挑战。为解决该问题,提出了高效可靠数据报ERD的RDMA QP通信机制,一方面通过可靠数据报RD来代替传统的RC,提高网卡的QP可扩展性;另一方面设计基于RD的可靠接收机制,在网络栈增加数据包丢包和快速有序处理,保证网络可靠性的同时提高传输性能。经过实验以及NS3仿真测试,ERD可以降低99.96%的QP数量,同时网络拥塞时传输性能可以提升15%以上。 展开更多
关键词 智算中心网络 AI大模型通信 远程直接存取协议 qp通信
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回火温度对预变形QP980钢组织与性能的影响
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作者 张春 李颂勋 +2 位作者 王曦 徐飞越 陈文轩 《金属热处理》 北大核心 2026年第2期238-244,共7页
通过扫描电镜(SEM)、X射线衍射仪(XRD)和万能力学试验机等方法,系统研究了预变形4%的QP980钢经200~600℃回火处理后的微观组织演变以及力学性能。结果表明,预变形4%的QP980钢的显微组织仍为铁素体、马氏体和少量残留奥氏体。随着回火温... 通过扫描电镜(SEM)、X射线衍射仪(XRD)和万能力学试验机等方法,系统研究了预变形4%的QP980钢经200~600℃回火处理后的微观组织演变以及力学性能。结果表明,预变形4%的QP980钢的显微组织仍为铁素体、马氏体和少量残留奥氏体。随着回火温度升高,马氏体与残留奥氏体逐渐分解,并伴随析出细小弥散的过渡η-Fe_(2)C碳化物,最终在600℃转变为稳定的θ-Fe_(3)C,形成回火索氏体。在此过程中,试样的强度与硬度随回火温度升高呈先增后降的趋势,在300℃回火时显微硬度达到峰值(340 HV0.5),断后伸长率则先略降后回升。经300℃×20 min回火后,试样可获得较理想的强塑性匹配(抗拉强度1267 MPa,断后伸长率17.2%),这主要归因于残留奥氏体的TRIP效应及过渡碳化物的弥散强化。拉伸断口分析显示,所有试样均存在明显韧窝,表现为典型韧性断裂,其中300~400℃回火断口较光滑,500~600℃回火时“颈缩”程度更为显著。 展开更多
关键词 qp980钢 预变形 回火温度 微观组织 力学性能
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充氢时间对QP980钢拉伸性能和断裂行为的影响
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作者 阮昕懿 尹晶晶 +1 位作者 常智渊 兰亮云 《东北大学学报(自然科学版)》 北大核心 2026年第1期115-122,共8页
采用电化学充氢与慢应变速率拉伸(SSRT)实验研究充氢时间对QP980钢复相组织氢脆特性的影响.应力-应变曲线结果表明,随充氢时间延长,抗拉强度与延伸率显著下降,但氢的存在不影响断裂前的加工硬化速率.断口形貌分析表明,在无氢情况下,试... 采用电化学充氢与慢应变速率拉伸(SSRT)实验研究充氢时间对QP980钢复相组织氢脆特性的影响.应力-应变曲线结果表明,随充氢时间延长,抗拉强度与延伸率显著下降,但氢的存在不影响断裂前的加工硬化速率.断口形貌分析表明,在无氢情况下,试样中部为韧窝与准解理混合断裂,边缘部分为韧窝断裂;充氢后试样的混合断裂区增大,且随充氢时间的延长,准解理单元刻面尺寸增大.通过二次裂纹和组织观察发现,当氢浓度较低时,铁素体与马氏体的相界面成为裂纹源主要位置,裂纹沿马氏体与铁素体相界面扩展并被铁素体钝化,形成微孔缩聚式裂纹,表明此时氢致局部塑性理论(HELP)为氢脆主导机制;当氢浓度较高时,裂纹转变为发丝状裂纹并穿过基体铁素体组织内部,表明氢致弱键理论(HEDE)为主导机制. 展开更多
关键词 qp980钢 充氢 氢致裂纹 慢应变速率拉伸 氢脆机制
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Insights into Student Perceptions of Error Feedback and Improvement Preferences in Online Programming Education
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作者 Li Zhang Tianze Wang +1 位作者 Jing Jiang Yufei Zhou 《计算机教育》 2026年第3期176-189,共14页
Online programming platforms are popular in programming education.However,there has been no research investigating students’real opinions and expectations of the error feedback mechanisms,leaving educators without a ... Online programming platforms are popular in programming education.However,there has been no research investigating students’real opinions and expectations of the error feedback mechanisms,leaving educators without a solid data foundation when attempting to improve the error feedback mechanisms.This paper makes a survey of 834 students across various programming courses and investigates student perceptions of error feedback mechanisms on online programming platforms.It explores the effectiveness of existing feedback,student satisfaction,and preferences for potential improvements,focusing on automatic error localization and program repair mechanisms.Results reveal a significant portion of students are dissatisfied with current feedback due to its limited informativeness.Students also express a clear demand for stronger feedback mechanisms,such as error localization and repair hints.Nevertheless,they prefer feedback that subtly guides them toward solutions,rather than providing direct and explicit answers,valuing the opportunity to enhance their debugging skills.The findings suggest a need for balanced,educational-focused feedback mechanisms that aid learning while promoting independent problem-solving. 展开更多
关键词 Error feedback Online programming education program error localization Automated program repair
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Reprogramming induced neurons from olfactory ensheathing glial cells: A feasible approach for spinal cord injury repair
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作者 Javier Sierra María Portela-Lomba +1 位作者 Diana Simón M.Teresa Moreno-Flores 《Neural Regeneration Research》 2026年第1期296-297,共2页
Every year, around the world, between 250,000 and 500,000 people suffer a spinal cord injury(SCI). SCI is a devastating medical condition that arises from trauma or disease-induced damage to the spinal cord, disruptin... Every year, around the world, between 250,000 and 500,000 people suffer a spinal cord injury(SCI). SCI is a devastating medical condition that arises from trauma or disease-induced damage to the spinal cord, disrupting the neural connections that allow communication between the brain and the rest of the body, which results in varying degrees of motor and sensory impairment. Disconnection in the spinal tracts is an irreversible condition owing to the poor capacity for spontaneous axonal regeneration in the affected neurons. 展开更多
关键词 INJURY feasible programMING
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基于QP优化的双轮腿–单臂机器人全身运动规划
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作者 郭天帅 孙保帅 《人工智能与机器人研究》 2026年第1期138-145,共8页
针对双轮腿–单臂机器人在全身运动规划中的自由度冗余问题,本文提出了一种基于二次规划(QP)优化的运动规划方法。该方法将躯干运动视为机械臂运动链的延伸,将手臂与躯干作为一个整体运动系统进行建模与控制。以TITA-PiPER机器人为研究... 针对双轮腿–单臂机器人在全身运动规划中的自由度冗余问题,本文提出了一种基于二次规划(QP)优化的运动规划方法。该方法将躯干运动视为机械臂运动链的延伸,将手臂与躯干作为一个整体运动系统进行建模与控制。以TITA-PiPER机器人为研究对象,首先,通过建立机械臂末端位姿与七维广义关节速度之间的雅可比矩阵映射,并将该映射关系作为硬约束,以确保手臂末端任务具有最高优先级。然后,构造以关节运动平滑性为优化目标,同时融合关节限位、非完整约束及动态平衡稳定性的二次规划问题,从而统一求解出满足整体运动要求的七维广义关节加速度。仿真结果表明,该方法能够在保证手臂末端任务精确执行的同时,充分利用躯干的运动能力实现全身协调,为轮腿臂机器人的实时运动控制提供了有效的解决方案。 展开更多
关键词 双轮腿–单臂机器人 qp优化 运动规划 雅可比矩阵约束
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Effectiveness of a stepped self-care program for stroke survivors:A quasi-experimental study
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作者 Zihao Ruan Dan Wang +5 位作者 Wenna Wang Yongxia Mei Hui Wang Suyan Chen Qiushi Zhang Zhenxiang Zhang 《International Journal of Nursing Sciences》 2026年第1期45-52,I0004,共9页
Objectives This study aimed to evaluate the effectiveness of the stepped self-care program on the self-care,self-efficacy,and quality of life of stroke survivors.Methods This quasi-experimental study allocated 110 str... Objectives This study aimed to evaluate the effectiveness of the stepped self-care program on the self-care,self-efficacy,and quality of life of stroke survivors.Methods This quasi-experimental study allocated 110 stroke survivors from two neurology wards into an intervention group(n=55)who received the stepped self-care program and a control group(n=55)who received usual care from June to December 2023.The Self-Care of Stroke Inventory,Stroke Self-Efficacy Questionnaire,and the short version of the Stroke Specific Quality of Life Scale were administered at baseline(T0),immediately post-intervention(T_(1)),and at 1-month(T_(2))and 3-month(T_(3))follow-ups.Data were analyzed using repeated measures analyses of variance,and generalized estimating equations.Results A total of 48 participants in the intervention group and 50 participants in the control group completed the study.No statistically significant differences were observed at T0 in any of the measured indicators(all P>0.05).The study showed significant group,time,and group×time interaction effects across the assessed outcomes(all P<0.05).Follow-up between-group comparisons at T_(1),T_(2),and T_(3) indicated that the intervention group had significantly higher scores in self-care maintenance,self-care monitoring,self-care management,self-efficacy,and quality of life than the control group(all P<0.001).Conclusions The stepped self-care program significantly improved self-care behaviors,self-efficacy,and quality of life among stroke survivors.These findings support the broader implementation of this approach in post-discharge home self-care. 展开更多
关键词 Quality of life SELF-CARE SELF-EFFICACY Stepped care program STROKE
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Global Optimization Algorithm for Minimizing Linear Fractional Programming
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作者 ZHAO Peng SHEN Pei-ping ZHONG Zhe-wei 《Chinese Quarterly Journal of Mathematics》 2026年第1期50-59,共10页
In this paper,we study a class of Linear Fractional Programming on a nonempty bounded set,called the Problem(LFP),and design a branch and bound algorithm to find the global optimal solution of the problem(LFP).First,w... In this paper,we study a class of Linear Fractional Programming on a nonempty bounded set,called the Problem(LFP),and design a branch and bound algorithm to find the global optimal solution of the problem(LFP).First,we convert the problem(LFP)to the equivalent problem(EP2).Secondly,by applying the linear relaxation technique to the problem(EP2),the linear relaxation programming problem(LRP2Y)was obtained.Then,the overall framework of the algorithm is given,and the convergence and complexity of the algorithm are analyzed.Finally,experimental results are listed to illustrate the effectiveness of the algorithm. 展开更多
关键词 Global optimization Linear Fractional programming Branch and bound algorithm Linear relaxation
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Open-loop control of combustion instabilities in a full-scale annular ramjet combustor using linear genetic programming
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作者 Jianguo TAN Zheng XU +2 位作者 Yao LIU Dongdong ZHANG Yi HOU 《Chinese Journal of Aeronautics》 2026年第2期20-28,共9页
The operational demands of a wide range significantly exacerbate combustion instability issues within ramjet combustor.To suppress combustion oscillations,an open-loop control system utilizing Linear Genetic Programmi... The operational demands of a wide range significantly exacerbate combustion instability issues within ramjet combustor.To suppress combustion oscillations,an open-loop control system utilizing Linear Genetic Programming(LGP)has been developed for a full-scale annular ramjet combustor.The LGP is used to generate control laws that include multi-frequency forcing.These laws are then transformed into square waves to actuate the solenoid valve,which modulates the kerosene supply for open-loop control.The results show that the duty cycle has little effect on instability amplitude,whereas an increase in frequency leads to a remarked reduction in combustion amplitude.After five generations evolvements,the pressure amplitude is reduced by 40.6% under the optimal control law generated by LGP.Furthermore,the machine learning process is depicted using a proximity map of control law similarity,with the search pathway visualized by the steepest descent.All individuals go forward to the upper left corner of the map with the evolution process,terminating at the optimal individual of the fifth generation. 展开更多
关键词 Annular ramjet combustor Combustion instabilities Linear genetic programming Machine learning Open-loop control
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Training Program Reform and Curriculum Construction of Characteristic Software Innovation Talents Based on the Integration of Industry and Education
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作者 Yixian Liu Jun Guo +2 位作者 Bin Zhang Dongming Chen Zhiliang Zhu 《计算机教育》 2026年第3期190-198,共9页
Aiming at the problem of innovative talent training in the industry field in characteristic software colleges,combined with the actual situation of Software College of Northeastern University,this paper analyzes the c... Aiming at the problem of innovative talent training in the industry field in characteristic software colleges,combined with the actual situation of Software College of Northeastern University,this paper analyzes the construction requirements of characteristic talent training mode and training scheme,puts forward the reform of characteristic software innovative talent training scheme integrating production and education,and takes the characteristic direction of financial technology as an example to introduce the curriculum construction based on industry-education integration and school-enterprise cooperation. 展开更多
关键词 Integration of industry and education Characteristic talents cultivation program reform Curriculum construction
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CD44-targeting and ZIF-8 gated gold nanocage for programmed breast cancer therapy through Pt-induced immunogenic cell death
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作者 Xin Li Fei Xiong +7 位作者 Xudong Cao Wei Liu Haobo Chen Jiayu He Weina Zhang Longguang Tang Wei Huang Xikuang Yao 《Chinese Chemical Letters》 2026年第1期462-467,共6页
The field of nanomedicine has been revolutionized by the concept of immunogenic cell death(ICD)-enhanced cancer therapy,which holds immense promise for the efficient treatment of cancer.However,precise delivery of ICD... The field of nanomedicine has been revolutionized by the concept of immunogenic cell death(ICD)-enhanced cancer therapy,which holds immense promise for the efficient treatment of cancer.However,precise delivery of ICD inducer is severely hindered by complex biological barriers.How to design and build intelligent nanoplatform for adaptive and dynamic cancer therapy remains a big challenge.Herein,this article presents the design and preparation of CD44-targeting and ZIF-8 gated gold nanocage(Au@ZH) for programmed delivery of the 1,2-diaminocyclohexane-Pt(Ⅱ)(DACHPt) as ICD inducer.After actively targeting the CD44 on the surface of 4T1 tumor cell,this Pt-Au@ZH can be effectively endocytosed by the 4T1 cell and release the DACHPt in tumor acidic environment,resulting in ICD effect and superior antitumor efficacy both in vitro and in vivo in the presence of mild 808 nm laser irradiation.By integration of internal and external stimuli intelligently,this programmed nanoplatform is poised to become a cornerstone in the pursuit of effective and targeted cancer therapy in the foreseeable future. 展开更多
关键词 programmed drug release ZIF-8-gated Gold nanocage Immunogenic cell death Cancer therapy
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Quality-guaranteed Dubins Path Planning for USV Based on Mixed-integer Piecewise linear Programming for Addressing the Extended Minimum-time Intercept Problem
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作者 Xing Zhou Kelin Zhu +3 位作者 Shuang Liu Zhaoqing Li Wenxin Zhang Kang Du 《哈尔滨工程大学学报(英文版)》 2026年第1期216-227,共12页
During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive... During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive distance)to a moving target as quickly as possible,resulting in the extended minimum-time intercept problem(EMTIP).Existing research has primarily focused on the zero-distance intercept problem,MTIP,establishing the necessary or sufficient conditions for MTIP optimality,and utilizing analytic algorithms,such as root-finding algorithms,to calculate the optimal solutions.However,these approaches depend heavily on the properties of the analytic algorithm,making them inapplicable when problem settings change,such as in the case of a positive effective range or complicated target motions outside uniform rectilinear motion.In this study,an approach employing a high-accuracy and quality-guaranteed mixed-integer piecewise-linear program(QG-PWL)is proposed for the EMTIP.This program can accommodate different effective interception ranges and complicated target motions(variable velocity or complicated trajectories).The high accuracy and quality guarantees of QG-PWL originate from elegant strategies such as piecewise linearization and other developed operation strategies.The approximate error in the intercept path length is proved to be bounded to h^(2)/(4√2),where h is the piecewise length. 展开更多
关键词 Minimum-time intercept problem Dubins vehicle Mixed-integer piecewise-linear program LINEARIZATION Approximate error trigonometric function USV
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Laser-induced in situ reprogramming of magnetic shape memory composites for adaptive devices
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作者 Qianqian Zhang Rui Li +5 位作者 Yuan Tao Yiyu Chen Yanlei Hu Dong Wu Jiaru Chu Jiawen Li 《International Journal of Extreme Manufacturing》 2026年第1期767-779,共13页
Programmable/reprogrammable magneto-responsive composites(MRCs)are highly desirable for applications in soft robotics,morphable actuators,and biomedical devices due to their capabilities of undergoing reversible,compl... Programmable/reprogrammable magneto-responsive composites(MRCs)are highly desirable for applications in soft robotics,morphable actuators,and biomedical devices due to their capabilities of undergoing reversible,complex,untethered,and rapid deformations.However,current MRC-based devices primarily rely on soft matrices,which revert to their original shapes and cease functioning when external magnetic fields are removed.Moreover,their magnetization programming,deformations,and functioning need to alternate between encoding and actuation platforms,limiting the adaptability and efficiency.Here,we present a reprogrammable magnetic shape-memory composite(RM-SMC)integrating a shape-memory polymer(SMP)skeleton with phase-transition magnetic microcapsules.High-intensity laser melts microcapsules for magnetic realignment under programmed fields,while low-intensity laser softens SMP for structural reconfiguration without compromising integrity.This dual-laser strategy facilitates in situ magnetization programming,shape morphing,and function execution within a single material system.Our innovative approach enables unique applications,including omnidirectional multi-degree-of-freedom actuators that can activate light switches,solar trackers that optimize energy capture,and adaptive impellers that modulate fluid pumping.By eliminating platform alternation and enabling shape/function retention post-actuation,the RM-SMC platform overcomes critical limitations in conventional MRCs,establishing a paradigm for multifunctional devices requiring persistent configuration control and field-independent operation. 展开更多
关键词 magneto-responsive composites shape memory polymer in situ programming and deformation omnidirectional multi-degree of freedom actuator adjustable fluid pumping
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QP980淬火-配分钢热模拟激光焊接热影响区性能
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作者 王金凤 郭亿 +4 位作者 苏文超 车亚军 蔡笑宇 李文娟 徐肖飞 《焊接学报》 北大核心 2025年第7期1-8,共8页
文中采用Gleeble-3500热模拟系统对QP980淬火-配分钢激光焊接热影响区(heat affected zone,HAZ)不同亚区进行热模拟,通过研究HAZ不同亚区的组织和性能,并与焊接接头HAZ相同区域进行比较.结果表明,热模拟获得的焊接HAZ各亚区组织与激光... 文中采用Gleeble-3500热模拟系统对QP980淬火-配分钢激光焊接热影响区(heat affected zone,HAZ)不同亚区进行热模拟,通过研究HAZ不同亚区的组织和性能,并与焊接接头HAZ相同区域进行比较.结果表明,热模拟获得的焊接HAZ各亚区组织与激光焊接接头相同区域的组织一致.力学性能分析表明,在热模拟试样中,亚临界热影响区(sub-critical heat affected zone,SCHAZ)抗拉强度和硬度都最低,断后伸长率在整个焊接HAZ中最大.拉伸试验中SCHAZ发生了明显的伸长,表明延展性能相对较好.焊接接头横截面硬度分析表明,焊接接头的临界热影响区(inter-critical heat affected zone,ICHAZ)硬度低于母材(base metal, BM),为焊接接头的软化区.焊接接头的拉伸性能及横截面硬度分布表明焊接接头的薄弱区域位于焊接HAZ的ICHAZ,与模拟焊接HAZ的性能吻合.通过对SCHAZ的组织进行分析,相比BM的几何必须位错密度(geometrically necessary dislocations,GND)减少,平均晶粒尺寸增大,小角度晶界晶粒含量下降. 展开更多
关键词 qp980淬火-配分钢 激光焊接 模拟焊接热影响区 接头软化
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预淬火处理对超高强QP钢显微组织和力学性能的影响研究
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作者 朱娜琼 许明珠 +1 位作者 沈超 李麟 《热加工工艺》 北大核心 2025年第15期105-110,共6页
采用定量金相、SEM、TEM及XRD等检测技术结合室温拉伸试验,研究了预淬火处理对淬火-配分处理后超高强QP钢组织演变和力学性能的影响。结果表明:与未经预淬火的样品相比,经950℃预淬火的样品呈现细化的层片状组织,残余奥氏体以薄膜状为... 采用定量金相、SEM、TEM及XRD等检测技术结合室温拉伸试验,研究了预淬火处理对淬火-配分处理后超高强QP钢组织演变和力学性能的影响。结果表明:与未经预淬火的样品相比,经950℃预淬火的样品呈现细化的层片状组织,残余奥氏体以薄膜状为主并有少量块状,该组织有利于TRIP效应的发挥,同时可阻碍裂纹扩展,提高了实验钢的强塑性,在抗拉强度超过1200 MPa的情况下伸长率接近20%;当预淬火温度为990℃时,实验钢的组织呈等轴状特征,马氏体回火程度较高,造成残余奥氏体多呈块状分布而不利于TRIP效应发挥,加之组织内贝氏体及二次马氏体含量减少导致其强塑积下降。 展开更多
关键词 预淬火处理 qp 显微组织 力学性能 TRIP效应
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An SQP algorithm for mathematical programs with nonlinear complementarity constraints
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作者 朱志斌 简金宝 张聪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第5期659-668,共10页
In this paper, we describe a successive approximation and smooth sequential quadratic programming (SQP) method for mathematical programs with nonlinear complementarity constraints (MPCC). We introduce a class of s... In this paper, we describe a successive approximation and smooth sequential quadratic programming (SQP) method for mathematical programs with nonlinear complementarity constraints (MPCC). We introduce a class of smooth programs to approximate the MPCC. Using an 11 penalty function, the line search assures global convergence, while the superlinear convergence rate is shown under the strictly complementary and second-order sufficient conditions. Moreover, we prove that the current iterated point is an exact stationary point of the mathematical programs with equilibrium constraints (MPEC) when the algorithm terminates finitely. 展开更多
关键词 mathematical programs with equilibrium constraints (MPEC) Sqp algorithm successive approximation global convergence superlinear convergence rate
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不等厚异质QP1180/DP1180钢板激光拼焊接头组织及性能研究
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作者 李文娟 王金凤 +5 位作者 苏文超 车亚军 王晶 郭亿 王海林 张元好 《精密成形工程》 北大核心 2025年第7期69-78,共10页
目的解决高强度钢QP1180和DP1180在汽车轻量化应用方面存在的热影响区软化等问题,进行了不等厚异质QP1180/DP1180钢板激光拼焊接头组织及性能研究。方法对1.6 mm厚QP1180钢和1.2 mm厚DP1180钢进行激光拼焊,通过扫描电子显微镜、液压拉... 目的解决高强度钢QP1180和DP1180在汽车轻量化应用方面存在的热影响区软化等问题,进行了不等厚异质QP1180/DP1180钢板激光拼焊接头组织及性能研究。方法对1.6 mm厚QP1180钢和1.2 mm厚DP1180钢进行激光拼焊,通过扫描电子显微镜、液压拉伸试验机和维氏硬度计等设备研究热输入对焊接接头微观组织和力学性能的影响。结果在不同焊接工艺参数下,激光焊接接头均为全焊透状态且表面成形良好。随着热输入的增大,焊缝金属区向母材区的过渡逐渐平缓、凹陷变小,上下表面宽度均有所增大,焊缝金属区板条马氏体束随着热输入的增加而变长,条束间距亦变宽,且宽度分布不均匀。热输入对QP1180侧和DP1180侧热影响区晶粒大小变化的影响规律基本一致,即热输入越大,粗晶区和细晶区的晶粒尺寸越大,临界热影响区铁素体含量也越多,QP1180侧亚临界热影响区析出的碳化物颗粒越多,但对DP1180侧亚临界热影响区微观组织的影响不明显。焊接接头两侧都存在明显的软化区,DP1180侧软化更为显著。在本研究所用焊接热输入条件下,单向拉伸试验中试样均断裂在母材区,由断口分析可知,所有工艺参数下的试样均为韧性断裂。结论在能形成全焊透的焊接工艺窗口内,均获得抗拉强度达到母材强度95%以上、断后伸长率达到母材断后伸长率30%以上的焊接接头。 展开更多
关键词 qp1180钢 DP1180钢 激光拼焊 微观组织 力学性能
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QP1180淬火-配分钢激光焊接接头微观组织及力学性能
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作者 李文娟 王金凤 +4 位作者 苏文超 郭亿 车亚军 蔡笑宇 王海林 《精密成形工程》 北大核心 2025年第2期85-93,共9页
目的对QP1180淬火-配分超高强钢的激光焊接工艺进行研究,以获得没有缺陷、能满足汽车零部件使用要求的焊接接头。方法将1.6 mm厚的QP1180钢板作为母材,对其进行激光焊接,通过改变焊接速度和激光输出功率的方式改变焊接热输入;利用扫描... 目的对QP1180淬火-配分超高强钢的激光焊接工艺进行研究,以获得没有缺陷、能满足汽车零部件使用要求的焊接接头。方法将1.6 mm厚的QP1180钢板作为母材,对其进行激光焊接,通过改变焊接速度和激光输出功率的方式改变焊接热输入;利用扫描电子显微镜(SEM)、液压拉伸试验机和维氏硬度计等手段,研究热输入对接头宏观成形、界面组织演变规律及接头力学性能的影响。结果在调整激光焊接工艺参数的条件下,在焊缝表面均未发现明显缺陷,焊缝表面成形良好。随着热输入的增加,QP1180钢激光焊接接头焊缝金属区上下表面以及最窄区域的宽度均有所增加,并且在同样热输入条件下,激光输出功率对焊缝宽度的影响大于焊接速度的影响。母材平均硬度约为375HV,软化区位于亚临界热影响区,软化区宽度随着热输入的增加而变宽。与母材相比,软化区平均硬度下降17HV~52HV,细晶区硬度最高为536HV,较母材硬度大幅增加。在所有能实现焊透的热输入下,工艺参数对焊接接头的强度和塑性影响较小,且均能获得性能良好的焊缝。结论获得了没有缺陷并能满足汽车零部件使用要求的焊接接头。 展开更多
关键词 qp1180淬火-配分钢 激光焊接 工艺参数 微观组织
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AQP5调控细胞程序性死亡在干燥综合征中的研究现状 被引量:1
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作者 王友霞 李翠娟 +4 位作者 巩振东 呼睿 胡勇 张惜燕 王其鎏 《重庆医科大学学报》 北大核心 2025年第10期1385-1391,共7页
水通道蛋白5(aquaporin 5,AQP5)是一种能明显提升细胞膜水通透性,参与水的分泌、吸收过程,以及维持细胞内外水分子的平衡状态,跨膜转运水的特异性蛋白。细胞程序性死亡(programmed cell death,PCD)与干燥综合征(sj?gren’s syndrome,SS... 水通道蛋白5(aquaporin 5,AQP5)是一种能明显提升细胞膜水通透性,参与水的分泌、吸收过程,以及维持细胞内外水分子的平衡状态,跨膜转运水的特异性蛋白。细胞程序性死亡(programmed cell death,PCD)与干燥综合征(sj?gren’s syndrome,SS)的发生发展过程有着密切的联系。AQP5可能通过调节PCD机制,进而影响SS的发生与发展。本文综述了近年来关于AQP5在PCD相关的细胞凋亡、焦亡、自噬及铁死亡等过程调控中的分子机制,同时深入探讨了其对SS可能产生的潜在影响,旨在为SS的临床预防与治疗提供理论依据。 展开更多
关键词 水通道蛋白5 干燥综合征 细胞程序性死亡
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