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Effect of austenitizing condition on mechanical properties,microstructure and precipitation behavior of AISI H13 steel

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Journal of Iron and Steel Research(International) 2024年第1期31卷 143-156页

作者： an-gang ning Yang Liu Rui Gao Stephen Yue Ming-bo Wang Han-jie Guo College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Department of Mining and Materials Engineering McGill UniversityMontrealQCH3A 0C5Canada ASSAB Tooling Technology(Chongqing)Co. Ltd.Chongqing401120China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The effects of austenitizing temperature(1223,1303,and 1373 K)and holding time(1-1500 s)on the microstructure,mechanical properties,and precipitation behavior of the H13 hot work die steel were investigated.The results indicate a softening phenomenon when H13 steel is austenitized at 1303 K beyond 900 s and 1373 K beyond 600 s,respectively.For the sample held for 1200 s,the tensile strength is found capable of reaching up to 2.2 GPa when quenched from a temperature above 1303 K.Meanwhile,prior-austenite grain size increases with the increase in austenitizing temperature.The kinetic behavior of the precipitates(mainly MC-type carbides)in H13 steel could be elaborated through the principles set forth by the Arrhenius and Avrami equations.Finally,the comprehensive strengthening of the H13 steel was discussed in detail.The results show that the activation energy of the transformed fraction of carbides is higher than that of the diffusion process for common alloying elements(Cr,V,Mo,and Ni)found in the austenite.This suggests that it would be difficult for precipitates to dissolve into the matrix when H13 steel is austenitized at high temperatures.With the increasing austenitizing temperature,the precipitation fraction decreases,and the dislocation density increases.The dislocation strengthening is regarded as the dominant strengthening contributed to yield strength in as-quenched H13 steel.

关键词： H13 steel Austenitizing Mechanical property Precipitation behavior Comprehensive strengthening

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Nanoscale precipitates and comprehensive strengthening mechanism in AISI H13 steel

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1056-1064页

作者： Wen-wen Mao an-gang ning Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Special Melting and Reparation of High-end Metal Materials Beijing 100083China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuanShanxi 030024China

The effects of heat treatment on the precipitates and strengthening mechanism in AISI H13 steel were investigated. The results showed that the presence of nanoscale precipitates favorably affected grain refinement and improved the yield strength. The volume fraction of precipitates increased from 1.05% to 2.85% during tempering, whereas the average precipitate size first decreased then increased during tempering. Contributions to the yield strength arising from the various mechanisms were calculated quantificationally, and the results demonstrated that grain refinement and dislocation density most strongly influenced the yield strength. In addition, under the interaction of average size and volume fraction, precipitates＇ contribution to the yield strength ranged from 247.9 to 378.5 MPa. Finally, a root-mean-square summation law of σ = σg ＋ σs ＋（σd^2 ＋ σp^2）^1/2, where σg, σs, σd, and σp represent the contributions of fine-grain strengthening, solid-solution strengthening, dislocation strengthening, and precipitation strengthening, respectively, was confirmed as the most applicable for AISI H13 steel, which indicates a strong link between precipitates and dislocations in AISI H13 steel.

关键词： die steel precipitates strengthening dislocation

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综合物探方法在贵南高铁隧道基底隐伏岩溶探测中的应用

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工程地球物理学报 2024年第2期21卷 196-204页

作者：宁刚中铁第一勘察设计院集团有限公司甘肃铁道综合工程勘察院有限公司甘肃兰州730000

高铁隧道路线经过岩溶地区,勘察阶段由于地形和物探方法局限性的影响,不能完全勘察清楚岩溶发育情况。本文结合高密度地震映像、地质雷达、二维瞬态面波和钻探方法,详细研究了隧道施工阶段岩溶探查中各种方法的外业数据采集、处理方法... 详细信息

高铁隧道路线经过岩溶地区,勘察阶段由于地形和物探方法局限性的影响,不能完全勘察清楚岩溶发育情况。本文结合高密度地震映像、地质雷达、二维瞬态面波和钻探方法,详细研究了隧道施工阶段岩溶探查中各种方法的外业数据采集、处理方法、数据分析的注意事项。经过研究,将地震映像的主频提高到800 Hz,可分辨深度5~25 m、宽度10 m左右的空溶洞和充填溶洞;地质雷达有效能量提高到600 ns,可分辨深度30 m内岩溶通道。结合贵南高铁隧道基底岩溶探查中的各种典型图像特征,以及地质施工人员的要求,探讨了隧道基底岩溶探测资料物探地质解释的四类划分解释原则,满足了地质人员及设计施工对物探资料可读性的要求,为岩溶探测资料解释提供了参考。

关键词：岩溶探测隧道基底地震映像地质雷达瞬态面波

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Vulvovaginal myeloid sarcoma with massive pelvic floor infiltration: A case report and review of literature

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World Journal of Clinical Cases 2022年第23期10卷 8312-8322页

作者： Jia-Xi Wang Heng Zhang gang ning Li Bao Department of Radiology Key Laboratory of Obstetric&Gynecologic and Pediatric Diseases and Birth Defects of Ministry of EducationWest China Second University HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Radiology Renshou Maternity and Child Health HospitalMeishan 620500Sichuan ProvinceChina

BACKGROUND Myeloid sarcoma(MS),including isolated and leukaemic MS,is an extramedullary myeloid tumour.MS can involve any anatomical site,but MS of the female genital tract is rare,with the ovaries and uterine body and cervix being the most commonly seen sites.Involvement of the vagina and vulva is extremely rare.CASE SUMMARY We report a rare case of MS with involvement of the vulva and vagina and massive infiltration of the pelvic floor.A 26-year-old woman presented with a vulvar mass,irregular vaginal bleeding and night sweats.Magnetic resonance imaging demonstrated an ill-defined,irregular vulvovaginal mass with massive involvement of the paravaginal tissue,urethra,posterior wall of the bladder,and pelvic floor.The signal and enhancement of the huge mass was homogeneous without haemorrhage or necrosis.Positron emission tomography/computed tomography showed high fluorodeoxyglucose uptake by the mass.Peripheral blood count detected blast cells.Vulvovaginal mass and bone marrow biopsies were performed,and immunohistochemistry confirmed the diagnosis of acute myeloid leukaemia(M-2 type,FAB classification)and vulvovaginal MS.The patient was treated with induction chemotherapy followed by allogeneic haematopoietic stem cell transplantation,and achieved complete remission.A systemic review of the literature on vulvovaginal MS was conducted to explore this rare entity’s clinical and radiological features.CONCLUSION Vulvovaginal MS is extremely rare.Diagnosis of vulvovaginal MS can only be confirmed histopathologically.Even though its clinical and imaging presentations are nonspecific,MS should be considered in the differential diagnosis of a newly developed T2-hyperintense,homogeneously enhanced vulvovaginal mass,especially in a patient with suspected haematological malignancy.

关键词： Myeloid sarcoma Vagina Vulva Acute myeloid lukaemia Imaging examination Case report

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连杆工艺性优化仿真

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机械研究与应用 2024年第2期37卷 45-47页

作者：潘美芳夏焕金舒森王宁刚程敢峰中国中车戚墅堰机车有限公司江苏常州213011

为保证连杆加工精度及其使用过程中的刚度,其关键措施是优化连杆毛坯结构,选择合理的粗、精基准以及提高连杆的工艺性。基于现代制造技术和加工技术的研究应用,对连杆小头过渡圆弧尺寸及定位槽结构进行优化,以实现连杆工艺性的提高。采... 详细信息

为保证连杆加工精度及其使用过程中的刚度,其关键措施是优化连杆毛坯结构,选择合理的粗、精基准以及提高连杆的工艺性。基于现代制造技术和加工技术的研究应用,对连杆小头过渡圆弧尺寸及定位槽结构进行优化,以实现连杆工艺性的提高。采用VERICUT软件对连杆加工路径、加工参数及刀具长度等进行仿真优化。在设置好安全距离的前提下,得到最优刀具长度。在刀具长度、干涉间寻找平衡点,进一步提高连杆加工工艺性。

关键词：连杆插铣 VERICUT 加工仿真

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基于储能技术的复杂有源配电网供电可靠性分析

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自动化技术与应用 2024年第2期43卷 178-182页

作者：华明谭景明周杨兵杜宁刚蔺丽华国网西藏电力有限公司西藏拉萨850000 西安科技大学通信学院陕西西安710054

分布式发电设备经过有效布局和调度可降低资源浪费,但传统方法存在布局不合理、调度效果差等问题。为此,提出基于储能技术的复杂有源配电网供电可靠性分析。首先分析分布式储能技术的基本原理,以电荷状态评价储能系统的电流剩余电量;在... 详细信息

分布式发电设备经过有效布局和调度可降低资源浪费,但传统方法存在布局不合理、调度效果差等问题。为此,提出基于储能技术的复杂有源配电网供电可靠性分析。首先分析分布式储能技术的基本原理,以电荷状态评价储能系统的电流剩余电量;在负荷点指标加权运算下确定电力系统中各项指标值,获取有源配电网运行过程中负荷的具体变化,简化馈线区可靠性参数,采用蒙特卡罗法抽样各层样本,运算出系统可靠性指标的期望值,确定有源配电网故障分区,根据孤岛随机变量获得系统概率可靠性指标,实现对有源配电网可靠性的全面评估和分析。实验结果表明:所提方法能够模拟电网实际运行状态,评估准确性较高。

关键词：储能技术有源配电网概率统计法蒙特卡罗法孤岛

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工程造价改革与发展研究

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建筑技术 2024年第7期55卷 893-896页

作者：刘刚宁耿辉强王伟段文博王焱张云中国市政工程西南设计研究总院有限公司成都610081 北京住总第二开发建设有限公司北京100011

本研究对工程造价改革方案的总体思路和五项工作任务进行了梳理和详细解读,同时也分析了各地试点省市相关方案的关键内容,并指出各地深化造价改革方案存在的差异。对于造价改革的关注重点与改革方向也进行了深入解读,并提出了相应的观... 详细信息

本研究对工程造价改革方案的总体思路和五项工作任务进行了梳理和详细解读,同时也分析了各地试点省市相关方案的关键内容,并指出各地深化造价改革方案存在的差异。对于造价改革的关注重点与改革方向也进行了深入解读,并提出了相应的观点。在后资质时代工程造价业的发展现状下,对行业存在的核心问题进行了深入剖析,探讨了工程造价在高质量发展要求背景下未来的发展趋势。该研究旨在通过对工程造价改革及未来发展的全面理解,促进行业高质量发展。

关键词：工程造价改革方案监管

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Decreased AKAP4/PKA signaling pathway in high DFI sperm affects sperm capacitation

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Asian Journal of Andrology 2024年第1期26卷 25-33页

作者： Kun Zhang Xiu-Hua Xu Jian Wu ning Wang gang Li Gui-Min Hao Jin-Feng Cao Hebei Key Laboratory of Infertility and Genetics Department of Reproductive MedicineSecond Hospital of Hebei Medical UniversityShijiazhuang 050000China Department of Reproductive Medicine Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000China Department of Neurology The 980th Hospital of the People's Liberation Army Joint Logistics Support Force(Bethune International Peace Hospital)Shijiazhuang 050000China.

The sperm DNA fragmentation index(DFI)is a metric used to assess DNA fragmentation within sperm.During in vitro fertilizationembryo transfer(IVF-ET),high sperm DFI can lead to a low fertilization rate,poor embryo development,early miscarriage,etc.A kinase anchoring protein(AKAP)is a scaffold protein that can bind protein kinase A(PKA)to subcellular sites of specific substrates and protects the biophosphorylation reaction.Sperm protein antigen 17(SPA17)can also bind to AKAP.This study intends to explore the reason for the decreased fertilization rate observed in high sperm DFI(H-DFI)patients during IVF-ET.In addition,the study investigates the expression of AKAP,protein kinase A regulatory subunit(PKARIl),and SPA17 between H-DFI and low sperm DFI(L-DFI)patients.SPA17 at the transcriptional level is abnormal,the translational level increases in H-DFI patients,and the expression of AKAP4/PKARIl protein decreases.H,O,has been used to simulate oxidative stress damage to spermatozoa during the formation of sperm DFI.It indicates that H,O,increases the expression of sperm SPA17 protein and suppresses AKAP4/PKARIl protein expression.These processes inhibit sperm capacitation and reduce acrosomal reactions.Embryo culture data and IVF outcomes have been documented.The H-DFI group has a lower fertilization rate.Therefore,the results indicate that the possible causes for the decreased fertilization rate in the H-DFI patients have included loss of sperm AKAP4/PKARIl proteins,blocked sperm capacitation,and reduced occurrence of acrosome reaction.

关键词： AKAP PKA SPA17 sperm capacitation sperm DNA fragmentation index

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Interface stabilization of 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether to high-voltage Li-rich Mn-based layered cathode materials

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Rare Metals 2022年第3期41卷 822-829页

作者： A-Lin Li Guo-Hua Li Shi-gang Lu Zhi-Min Ren Jian-Tao Wang Hao-Xiang Zhuo Wei Quan gang-ning Zhang Fu-Juan Han Yi-Mian Xia Jing Wang Yi Zhang National Power Battery Innovation Center Grinm Group Company LtdBeijing 100088China China Automotive Battery Research Institute Company Ltd Beijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China Materials Genome Institute Shanghai UniversityShanghai 200444China

Non-aqueous electrolyte solvents play a pivotal role in improving the cycling performance of high-voltage Li-rich Mn-based layered cathode materials. In this study, a fluoroether (1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, TFEPE) was added to 1.2 mol·L^(-1)LiPF_(6)EC/EMC/DEC at different concentrations to synthesize a series of electrolytes for enhancing the cycling performance of highvoltage Li_(1.18)Mn_(0.50)Ni_(0.26)Co_(0.06)O_(2)(LMNC).

关键词： materials. cycling 1,2

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On-chip spiking neural networks based on add-drop ring microresonators and electrically reconfigurable phase-change material photonic switches

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Photonics Research 2024年第4期12卷 755-766页

作者： QIANG ZHANG ning JIANG YIQUN ZHANG ANRAN LI HUANHUAN XIONG gang HU YONGSHENG CAO KUN QIU School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

We propose and numerically demonstrate a photonic computing primitive designed for integrated spiking neural networks (SNNs) based on add-drop ring microresonators (ADRMRs) and electrically reconfigurable phasechange material (PCM) photonic switches. In this neuromorphic system, the passive silicon-based ADRMR,equipped with a power-tunable auxiliary light, effectively demonstrates nonlinearity-induced dual neural dynamics encompassing spiking response and synaptic plasticity that can generate single-wavelength optical neural spikes with synaptic weight. By cascading these ADRMRs with different resonant wavelengths, weighted multiple-wavelength spikes can be feasibly output from the ADRMR-based hardware arrays when external wavelengthaddressable optical pulses are injected;subsequently, the cumulative power of these weighted output spikes is utilized to ascertain the activation status of the reconfigurable PCM photonic switches. Moreover, the reconfigurable mechanism driving the interconversion of the PCMs between the resonant-bonded crystalline states and the covalent-bonded amorphous states is achieved through precise thermal modulation. Drawing from the thermal properties, an innovative thermodynamic leaky integrate-and-firing (TLIF) neuron system is proposed. With the TLIF neuron system as the fundamental unit, a fully connected SNN is constructed to complete a classic deep learning task:the recognition of handwritten digit patterns. The simulation results reveal that the exemplary SNN can effectively recognize 10 numbers directly in the optical domain by employing the surrogate gradient algorithm. The theoretical verification of our architecture paves a whole new path for integrated photonic SNNs, with the potential to advance the field of neuromorphic photonic systems and enable more efficient spiking information processing.

关键词： neural networks precise

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