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Precipitation behavior and martensite lath coarsening during tempering of T/P92 ferritic heat-resistant steel

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 438-447页

作者： lin-qing xu Dan-tian Zhang Yong-chang Liu Bao-qun Ning Zhi-xia Qiao Ze-sheng Yan Hui-jun Li State Key Lab of Hydaulic Engineering Simulation and Safety School of Material Science and EngineeringTianjin University School of Materials Science and Engineering Tianjin University of Technology School of Mechanical Engineering Tianjin University of Commerce

Tempering is an important process for T/P92 ferritic heat-resistant steel from the viewpoint of microstructure control, as it facili- tates the formation of final tempered martensite under serving conditions. In this study, we have gained deeper insights on the mechanism underlying the microstructural evolution during tempering treatment, including the precipitation of carbides and the coarsening of martensite laths, as systematically analyzed by optical microscopy, transmission electron microscopy, and high-resolution transmission electron mi- croscopy. The chemical composition of the precipitates was analyzed using energy dispersive X-ray spectroscopy. Results indicate the for- mation of M3C （cementite） precipitates under normalized conditions. However, they tend to dissolve within a short time of tempering, owing to their low thermal stability. This phenomenon was substantiated by X-ray diffraction analysis. Besides, we could observe the precipitation of fine carbonitrides （MX） along the dislocations. The mechanism of carbon diffusion controlled growth of M23C6 can be expressed by the Zener＇s equation. The movement of Y-junctions was determined to be the fundamental mechanism underlying the martensite lath coarsening process. Vickers hardness was estimated to determine their mechanical properties. Based on the comprehensive analysis of both the micro- structural evolution and hardness variation, the process of tempering can be separated into three steps.

关键词： ferritic steel heat resisting tempering precipitation martensite coarsening

Effects of the long wavelength-filtered continuousspectrum on natural refractive development in juvenile guinea pigs

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International Journal of Ophthalmology(English edition) 2019年第6期12卷 883-891页

作者： Rui-Qin Li Wei-Zhong Lan Xiao-Ning Li Hao-Ran Wu qing-lin xu Hong Zhong Wen-Tao Li Zhi-Kuan Yang Aier School of Ophthalmology Central South UniversityChangsha 410015Hunan ProvinceChina Aier Institute of Optometry and Vision Science Changsha 410015Hunan ProvinceChina Huizhou Third People’s Hospital Guangzhou Medical UniversityHuizhou 516002Guangdong ProvinceChina

AIM: To investigate the effects of spectral composition and light intensity on natural refractive development in guinea ***: A total of 124 pigmented guinea pigs(2-week-old) were randomly assigned to three groups at high(Hi;4000 lx), medium(Me;400 lx) and low(Lo;50 lx) light intensities under a 12:12 light/dark cycle for 6 wk. Each group was subdivided into subgroups with the following spectra: broad spectrum Solux halogen light(BS), 600 nm above-filtered continuous spectrum(600F), 530 nm above-filtered continuous spectrum(530F), and 480 nm above-filtered continuous spectrum(480F;HiBS: n=10, Hi600F: n=10, Hi530F: n=10, Hi480F: n=10, MeBS: n=10, Me600F: n=10, Me530F: n=10, Me480F: n=10, LoBS: n=11, Lo600F: n=12, Lo530F: n=10, Lo480F: n=11). Refractive error, corneal curvature radius, and axial dimensions were determined by cycloplegic retinoscopy, photokeratometry, and A-scan ultrasonography before and after 2, 4, and 6 wk of treatment. Average changes from both eyes in the ocular parameters and refractive error were compared among different ***: After 6 wk of exposure, high-intensity lighting enhanced hyperopic shift;medium-and low-intensity lighting enhanced myopic shift(P<0.05). Under the same spectrum, axial increase was larger in the low light intensity group than in the medium and high light intensity groups(HiBS: 0.65±0.02 mm, MeBS: 0.67±0.01 mm, LoBS:0.82±0.02 mm;Hi600 F: 0.64±0.02 mm, Me600F: 0.67±0.01 mm, Lo600F: 0.81±0.01 mm;Hi530F: 0.64±0.02 mm, Me530F: 0.67±0.01 mm, Lo530F: 0.73±0.02 mm;Hi480F: 0.64±0.01 mm, Me480F: 0.66±0.01 mm, Lo480F: 0.72±0.02 mm;P<0.05). Under 400 lx, there was a faster axial increase in the MeBS group than in the Me480F group(P<0.05). Under 50 lx, axial length changes were significantly larger in LoBS and Lo600F than in Lo530F and Lo480F(P<0.01).CONCLUSION: Under high-intensity lighting, high light intensity rather than spectrum distributions that inhibits axial increase. Under medium-and low-intensity lighti

关键词： myopia wavelength spectral composition light intensity refractive development

离子色谱法测定核电厂含硼酸水中的碱金属和碱土金属离子

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原子能科学技术 2017年第1期51卷 8-12页

作者：林清湖徐天凤海南核电有限公司海南昌江570133

核电厂含硼酸系统水质中金属离子含量的分析常采用原子吸收光谱法和电感耦合等离子体发射光谱法。在硼酸存在下,原子吸收光谱法分析金属离子时回收率和准确性明显偏低;电感耦合等离子体发射光谱法检测能力有限,无法满足痕量金属离子分... 详细信息

核电厂含硼酸系统水质中金属离子含量的分析常采用原子吸收光谱法和电感耦合等离子体发射光谱法。在硼酸存在下,原子吸收光谱法分析金属离子时回收率和准确性明显偏低;电感耦合等离子体发射光谱法检测能力有限,无法满足痕量金属离子分析需求。本文采用离子色谱法,利用抑制器中离子交换膜的选择透过性在线去除硼酸,消除硼酸对金属离子测量的影响,实现金属离子的准确测量。结果表明,Li+、Na+、K+、Mg^(2+)、Ca^(2+)的测量加标回收率为97.0%~102.3%,相对标准偏差为0.54%~1.25%(n=7),方法检测限为2.58~40.38ng/L。该方法具有操作简单、稳定可靠、分析速度快、检测限低等优点。

关键词：含硼酸水离子色谱痕量金属离子

Understanding SARS with Wolfram Approach

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Acta Biochimica et Biophysica Sinica 2004年第1期36卷 1-10页

作者： Da-Wei LI, Yu-Xi PAN, Yun DUAN, Zhen-De HUNG, Ming-qing xu, and lin HE ( Bio-X Life Science Research Center, Shanghai Jiao Tong University, Shanghai 200030, China Institute for Nutritional science, the Chinese Academy of Sciences, Shanghai 200031, China ) Bio-X Life Science Research Center Shanghai Jiao Tong University Shanghai 200030 China.

Stepping acquired immunodeficiency syndrome (AIDS), severe acute respiratory syndrome (SARS) as another type of disease has been threatening mankind since late last year. Many scientists worldwide are making great efforts to study the etiology of this disease with different approaches. 13 species of SARS virus have been sequenced. However, most people still largely rely on the traditional methods with some disadvantages. In this work, we used Wolfram approach to study the relationship among SARS viruses and between SARS viruses and other types of viruses, the effect of variations on the whole genome and the advantages in the analysis of SARS based on this novel approach. As a result, the similarities between SARS viruses and other coronavirusxes are not really higher than those between SARS viruses and non-coronaviruses.

关键词： genome sequence SARS visualization Wolfram approach

Pyroptosis,ferroptosis,and autophagy in spinal cord injury:regulatory mechanisms and therapeutic targets

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Neural Regeneration Research 2025年第10期20卷 2787-2806页

作者： qingcong Zheng Du Wang Rongjie lin Weihong xu Department of Spinal Surgery the First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Arthritis Clinical and Research Center Peking University People’s HospitalBeijingChina Department of Orthopedic Surgery Fujian Medical University Union HospitalFuzhouFujian ProvinceChina

Regulated cell death is a form of cell death that is actively controlled by *** studies have shown that regulated cell death plays a key role after spinal cord *** and ferroptosis are newly discovered types of regulated cell deaths that have been shown to exacerbate inflammation and lead to cell death in damaged spinal ***,a complex form of cell death that is interconnected with various regulated cell death mechanisms,has garnered significant attention in the study of spinal cord *** injury triggers not only cell death but also cellular survival *** signaling pathways play pivotal roles in influencing the processes of both deterioration and repair in spinal cord injury by regulating pyroptosis,ferroptosis,and ***,this review aims to comprehensively examine the mechanisms underlying regulated cell deaths,the signaling pathways that modulate these mechanisms,and the potential therapeutic targets for spinal cord *** analysis suggests that targeting the common regulatory signaling pathways of different regulated cell deaths could be a promising strategy to promote cell survival and enhance the repair of spinal cord ***,a holistic approach that incorporates multiple regulated cell deaths and their regulatory pathways presents a promising multi-target therapeutic strategy for the management of spinal cord injury.

关键词： autophagy cell death ferroptosis inflammation pathological mechanisms pyroptosis regulated cell death regulatory pathways spinal cord injury therapeutic targets

An overview on SAR measurements of sea surface wind

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Progress in Natural Science:Materials International 2008年第8期18卷 913-919页

作者： Hui lin a, qing xu a,*, Quanan Zheng b a Institute of Space and Earth Information Science, The Chinese University of Hong Kong, Room 615, Esther Lee Building, Hong Kong, China b Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA Institute of Space and Earth Information Science The Chinese University of Hong Kong Room 615 Esther Lee Building Hong Kong China Department of Atmospheric and Oceanic Science University of Maryland College Park MD USA

Studies show that synthetic aperture radar (SAR) has the capability of providing high-resolution (sub-kilometer) sea surface wind fields. This is very useful for applications where knowledge of the sea surface wind at fine scales is crucial. This paper aims to review the latest work on sea surface wind field retrieval using SAR images. As shown, many different approaches have been developed for retrieving wind speed and wind direction. However, much more work will be required to fully exploit the SAR data for improving the retrieval accuracy of high-resolution winds and for producing wind products in an operational sense.

关键词： SAR Sea surface wind Wind retrieval algorithms

Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第1期68卷 329-336页

作者： Yuzhu Li Yumeng Gao Feng Tian Yu Wang Yuan Yao Shaoliang lin Xiang Ma Binbin xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular Engineering East China University of Science & Technology

Developing organic room-temperature phosphorescence （RTP） materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis（4-alkoxyphenyl）ethane-1,2-dione-alt-（ethylene glycol）x)(P（Bz-alt-EGx）) that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly （COA） process,P（Bz-alt-EGx） self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly （TA） of P（Bz-alt-EGx） obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution （between blue and yellow-green,over125 nm） is realized using the P（Bz-alt-EGx） alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

关键词： self-assembly conformation ordering alternating copolymer phosphorescence emission

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： qing He Zhen Wang Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge xu Gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

Multi-model ensemble learning for battery state-of-health estimation:Recent advances and perspectives

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Journal of Energy Chemistry 2025年第1期100卷 739-759页

作者： Chuanping lin Jun xu Delong Jiang Jiayang Hou Ying Liang Zhongyue Zou xuesong Mei State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi'an Jiaotong University Department of Electrical Engineering and Automation Luoyang Institute of Science and Technology School of Mechanical Engineering Hangzhou Dianzi University

The burgeoning market for lithium-ion batteries has stimulated a growing need for more reliable battery performance monitoring. Accurate state-of-health(SOH) estimation is critical for ensuring battery operational performance. Despite numerous data-driven methods reported in existing research for battery SOH estimation, these methods often exhibit inconsistent performance across different application scenarios. To address this issue and overcome the performance limitations of individual data-driven models,integrating multiple models for SOH estimation has received considerable attention. Ensemble learning(EL) typically leverages the strengths of multiple base models to achieve more robust and accurate outputs. However, the lack of a clear review of current research hinders the further development of ensemble methods in SOH estimation. Therefore, this paper comprehensively reviews multi-model ensemble learning methods for battery SOH estimation. First, existing ensemble methods are systematically categorized into 6 classes based on their combination strategies. Different realizations and underlying connections are meticulously analyzed for each category of EL methods, highlighting distinctions, innovations, and typical applications. Subsequently, these ensemble methods are comprehensively compared in terms of base models, combination strategies, and publication trends. Evaluations across 6 dimensions underscore the outstanding performance of stacking-based ensemble methods. Following this, these ensemble methods are further inspected from the perspectives of weighted ensemble and diversity, aiming to inspire potential approaches for enhancing ensemble performance. Moreover, addressing challenges such as base model selection, measuring model robustness and uncertainty, and interpretability of ensemble models in practical applications is emphasized. Finally, future research prospects are outlined, specifically noting that deep learning ensemble is poised to advance ens

关键词： Contrastive Learning