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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第10期14卷 760-766页

作者： Li-yan DAI qiu-long shi Jing ZHANG Xiao-zhong WANG Ying-qi CHEN Department of Chemical and Biological Engineering Zhejiang University

Solubility of 2-amino-6-chloropurine in Mitsunobu solvents could be significantly improved after its exocyclic amino group is protected via *** bis-Boc protected 2-amino-6-chloropurine also shows excellent activity and N9 selectivity in the coupling with various alcohols by a Mitsunobu ***,a new practical and efficient method is established for the synthesis of penciclovir(PCV) from bis-Boc-2-amino-6-chloropurine 9 and the side chain of 5-(2-hydroxyethyl)-2,2-dimethyl-1,3-dioxane 5—the latter being a more easily prepared cyclic precursor of the diacetate side chain used in the conventional *** coupling of 9 with 5 proceeded regioselectively at a N9 position of purine derivative for a good yield under Mitsunobu conditions.

关键词： 2-amino-6-chloropurine Mitsunobu reaction bis-Boc protection Penciclovir(PCV)

薄膜/涂层材料界面结合强度评价方法研究进展

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表面技术 2022年第4期51卷 50-65页

作者：潘晓龙胡小刚赵婧邱龙时西安稀有金属材料研究院有限公司西安710016

薄膜/涂层与基体间的结合强度作为评价膜层质量的关键指标之一,是保证膜层满足力学、电学、光学以及磁学等使用性能的根本前提。薄膜/涂层材料界面结合性能的表征是表面科学与工程领域的重要组成部分,亦是研判和预防界面失效的基本依据... 详细信息

薄膜/涂层与基体间的结合强度作为评价膜层质量的关键指标之一,是保证膜层满足力学、电学、光学以及磁学等使用性能的根本前提。薄膜/涂层材料界面结合性能的表征是表面科学与工程领域的重要组成部分,亦是研判和预防界面失效的基本依据。近年来,新材料、新装备、新技术和新工艺的不断涌现,加剧了界面微观结构的复杂性和结果的不可预测性,同时对膜/基界面结合强度的评价也提出了更高的要求。目前,用于膜/基界面结合强度的评价方法种类繁多,测试原理各异,适用范围不同,且尚无一种方法适用于所有的材料体系。准确评价膜/基界面结合强度对界面性能的控制、改善,以及对膜层的服役行为和寿命的预估具有重要指导意义。首先,简要介绍了界面结合强度的物理含义,明晰了“本征结合强度”与“实际结合强度”间的差异,并从断裂力学的角度描述了界面结合强度的表征模型。然后,将当前常用的评价方法按照加载方式划分为静态加载方法(包括拉伸法、剥离法、划痕法、压入法、鼓泡法、弯曲法等)和动态加载方法(往复划痕法、冲击法、循环压入法、接触疲劳法等),并进行了分类评述。系统梳理了各种评价方法的基本原理、技术特点、力学模型,概括了不同评价方法的优势及不足。此外,归纳了适用的涂层材料体系和涂层厚度范围,综述了薄膜/涂层材料界面结合强度评价方法的研究现状。在静态评价方法中,划痕法和表面压入法因具有测试简单、耗时少、试样无需特殊处理,且有专业商用化设备可供使用等优点,是目前最为常用的膜基结合强度测试方法。相较于静态方法,采用动态方法来评价界面结合强度更加贴近服役工况,可为薄膜/涂层材料失效提供更为准确的预判。在动态评价方法中,滚动接触疲劳法和循环压入法具有对界面因素敏感、可定量化和可动态化监测等优点,在膜基结合强度评价上展示出良好的应用前景。最后,展望了界面结合强度评价方法未来的发展方向,未来应当开发更加高效、准确的评价方法,构建统一的评价标准和表征参量,建立完整的界面安全和失效评价体系,以期为膜/基界面结合强度的合理及准确评价提供参考,拓展薄膜/涂层材料在新领域和新方向上的应用广度和深度。

关键词：薄膜涂层界面结合强度评价方法

Tangled but ordered human mitochondrial tRNA maturation

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Science China Life Sciences 2025年

作者： shi-Ying Yao Xiao-long Zhou Key Laboratory of RNA Innovation Science and Engineering CAS Center for Excellence in Molecular Cell Science Shanghai Institute of Biochemistry and Cell Biology Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Systems Health Science of Zhejiang Province School of Life Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences

Mitochondria are cellular organelles that originate from an endosymbiotic bacterial ancestor and are primarily responsible for ATP generation via oxidative phosphorylation (OXPHOS). OXPHOS is conducted by five mitochondrial respiratory complexes in the inner mitochondrial membrane. Human mitochondria possess a distinct genome, a small, circular, doublestranded DNA (mtDNA) of 16,569 base pairs.

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An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai Liu Zhe Wang MengXi shi Willie Soon shiCan qiu Department of Geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for Environmental Research and Earth Sciences(CERES) SalemMA 01970USA Institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

High-temperature oxidation behavior and degradation mechanism of chromium-coated zirconium alloy cladding: a review

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Tungsten 2025年第1期7卷 50-70页

作者： Yi Li Bei-Qi Wang Xin-Yin Zhang shi-Jie Wang Cong-Yi Li Hui-long Yang Ran-Ran Su Tong Liu School of Mechanical Engineering Shanghai Jiao Tong University College and Graduate School of Arts and Sciences University of Virginia Global Institute of Future Technology Shanghai Jiao Tong University

Accident-tolerant fuels(ATF) have been extensively studied to reduce the production rate and total amount of heat and hydrogen generated from high-temperature steam oxidation during severe ***-coated zirconium alloy cladding has become one of the most promising candidates for ATF because of its excellent corrosion and oxidation *** paper provides a comprehensive overview of the research progress on oxidation behaviors and degradation mechanisms in chromium-coated zirconium alloy cladding under high-temperature *** techniques to strengthen the oxidation resistance are highlighted and ***,challenges and opportunities for various future directions are addressed.

关键词： Accident-tolerant fuel Chromium coating Degradation mechanism High-temperature oxidation behavior Zirconium alloy cladding

Calibration of the Solar X-ray Detector on-board the Macao Science Satellite-1B for Soft X-ray Detection

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Science China Earth Sciences 2025年第1期68卷 11-26页

作者： Man-Hei NG Xiaoping ZHANG Jianwu CHEN Yongqiang shi Fuchang ZUO Wenxi PENG Weichun FU Liansheng LI Pengwei LUO Chi-long TANG Guozheng ZHANG Zhiwu MEI Li WANG Cunhui LI Jiaming OU Yanyan XU State Key Laboratory of Lunar and Planetary Sciences Macau University of Science and Technology China National Space Administration (CNSA) Macau Center for Space Exploration and Science Space Optoelectronic Measurement and Perception Laboratory Beijing Institute of Control Engineering Institute of High Energy Physics Chinese Academy of Sciences Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of Physics

The Solar X-ray Detector(SXD) on-board the Macao Science Satellite-1B(MSS-1B) was successfully launched via the Chinese long March-2C rocket on 21 May 2023, and commenced operations in early June of the same year. The MSS-1B/Soft X-ray Detection Units(SXDUs) employ two silicon drift detectors(SDDs), providing a wide range of energy spectra spanning from 0.7 to 24 keV. Notably, the SXDUs deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 second. Here, we perform thorough calibrations of the MSS-1B/SXDUs, employing a combination of ground experiments and simulations. In addition, quantitative analysis comparing the flux measurements obtained by the MSS-1B/SXDUs to the data collected by the Geostationary Operational Environmental Satellite(GOES), provides compelling evidence of their consistency. Furthermore, the preliminary spectral analysis results showcase the robustness and expected performance of the MSS-1B/SXDUs, unlocking their potential for facilitating the study of dynamic evolution of solar flares. Moreover, the innovative MSS-1B/Solar X-ray Detector facilitates concurrent observations of solar soft and hard X-rays, thereby making valuable contributions to the advancements in solar research.

关键词： Macao Science Satellite-1B (MSS-1B) Calibration Solar X-Ray Detector Spectrometer Soft X-rays Solar flares Solar abundances

Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction

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Computers, Materials & Continua 2025年第1期82卷 1069-1086页

作者： shi Li Didi Sun College of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant ***-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying *** comprehension is crucial for making informed strategic decisions in various business and societal ***,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause *** address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment *** model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause ***,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among *** proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 *** results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its *** research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-c

关键词： Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms

Detection and Recognition of Spray Code Numbers on Can Surfaces Based on OCR

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Computers, Materials & Continua 2025年第1期82卷 1109-1128页

作者： Hailong Wang Junchao shi School of Computer Science Zhongyuan University of TechnologyZhengzhou450007China

A two-stage algorithm based on deep learning for the detection and recognition of can bottom spray codes and numbers is proposed to address the problems of small character areas and fast production line speeds in can bottom spray code number *** the coding number detection stage,Differentiable Binarization Network is used as the backbone network,combined with the Attention and Dilation Convolutions Path Aggregation Network feature fusion structure to enhance the model detection *** terms of text recognition,using the Scene Visual Text Recognition coding number recognition network for end-to-end training can alleviate the problem of coding recognition errors caused by image color distortion due to variations in lighting and background *** addition,model pruning and quantization are used to reduce the number ofmodel parameters to meet deployment requirements in resource-constrained environments.A comparative experiment was conducted using the dataset of tank bottom spray code numbers collected on-site,and a transfer experiment was conducted using the dataset of packaging box production *** experimental results show that the algorithm proposed in this study can effectively locate the coding of cans at different positions on the roller conveyor,and can accurately identify the coding numbers at high production line *** Hmean value of the coding number detection is 97.32%,and the accuracy of the coding number recognition is 98.21%.This verifies that the algorithm proposed in this paper has high accuracy in coding number detection and recognition.

关键词： Can coding recognition differentiable binarization network scene visual text recognition model pruning and quantification transport model

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镀锌钢板钼酸盐钝化膜防腐蚀性能研究

世界有色金属 2019年第15期44卷 134-136页

作者：田丰赵婧邱龙时潘晓龙西安稀有金属材料研究院有限公司

为避免铬酸盐钝化所带来的环境污染问题,并且提高镀锌钢板的耐蚀性能,寻找一种低毒的代替铬酸盐钝化处理工艺十分必要。本文采用钼酸盐对镀锌钢板表面进行钝化,以钼酸铵、磷酸钠、磷酸和硝酸为主要成分,辅以其它添加剂,利用中性盐雾腐... 详细信息

为避免铬酸盐钝化所带来的环境污染问题,并且提高镀锌钢板的耐蚀性能,寻找一种低毒的代替铬酸盐钝化处理工艺十分必要。本文采用钼酸盐对镀锌钢板表面进行钝化,以钼酸铵、磷酸钠、磷酸和硝酸为主要成分,辅以其它添加剂,利用中性盐雾腐蚀试验(NSS)以及动电位极化曲线,研究钝化液的组成、pH值、温度、钝化时间以及烘干温度、时间等因素对钝化成膜及其耐蚀性的影响。获得钝化处理最佳工艺参数:钼酸铵10g/L,适量磷酸盐及植酸添加剂,pH值2,钝化处理温度40℃,钝化时间90s,烘干温度40℃,烘干时间为15min。结果表明:钝化膜防腐蚀性能接近铬酸盐钝化膜的性能,此外钝化液对环境的污染极小,具有积极意义。

关键词：镀锌钢板钼酸盐钝化耐蚀性

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氧化交联PVA电池隔膜的性能研究

电池工业 2005年第3期10卷 153-155页

作者：张雪冰叶寅邱士龙中国科学院上海应用物理研究所上海201800

当电池使用强碱溶液作为电解液时,PVA隔膜在使用过程因水解而使电池性能下降。介绍了通过氧化交联的方法,显著地提高了隔膜的耐碱性和抗水溶性;报导了用涂布法自制的PVA隔膜与进口PVA隔膜在耐碱性、抗水溶性和面电阻方面的对比结果。结... 详细信息

当电池使用强碱溶液作为电解液时,PVA隔膜在使用过程因水解而使电池性能下降。介绍了通过氧化交联的方法,显著地提高了隔膜的耐碱性和抗水溶性;报导了用涂布法自制的PVA隔膜与进口PVA隔膜在耐碱性、抗水溶性和面电阻方面的对比结果。结果表明:自制的交联PVA隔膜具有明显的优势。

关键词：氧化交联 PVA 电池隔膜