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Influence of Hot Isostatic Pressing on Microstructuresand Properties of NiAl/Cr(Mo)-TiC in-situMultiphase Composites

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Journal of Materials Science & Technology 1998年第4期14卷 331-334页

作者： jiang, DT guo, JT Chinese Acad Sci Inst Met Res Shenyang 110015 Peoples R China

A novel in-situ multiphase NiAl-based composite was investigated on its microstructures and properties influenced by HIP treatment. In the as- processed composites, a fine array of NiAl precipitates was found to be distributed in Cr(Mo) phase. TiC particles tended to segregate at grain or phase boundaries. In addition, a number of dislocations were observed to exist in NiAl grains meanwhile fewer in Cr(Mo) grains. Little change in the morphology was found except that nearly fully densification was achieved. Some changes in microstructures were notable including coarsening of NiAl precipitates in Cr(Mo) phase and increase in dislocation density in NiAl phase. After HIP, the strength of the composites increased significantly compared with the as-processed composites. The reason for the enhanced strength of the composites is also discussed.

关键词： Metallic matrix composites

Genetic Analysis and Gene-Mapping of Two Reduced-Culm-Number Mutants in Rice

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Journal of Integrative Plant Biology 2006年第3期48卷 341-347页

作者： Hua jiang Long-Biao guo Da-Wei Xue Da-Li Zeng Guang-heng Zhang guo-Jun Dong Ming-Hong Gu Qian Qian State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006 China Agricultural College Yangzhou University Yangzhou 225006 China

In the present study, In order to systematically dissect the genetic mechanism of rice （Oryza satlva L.） tilling for the super rice ideotype and the model system of branching development, two ethyl methane suifonate-induced rice reduced-culm-number（rcn） mutants from the progeny of Nippobare （O. satlva ssp. japonica）, namely rcn8 and rcn9, were used. Their maximum tillers were both less than 4. in addition, rcn9 had another major feature of rust-spotted leaves. Allelic tests between these two mutants and seven other recessive few-tiller mutants revealed that they were previously unknown loci. Genetic analysis showed that the rcn traits were all controlled by a pair of different recessive genes, designated as RCN8and RCNg, respectively. Two F2 populations derived from crosses between the rcn8 or rcn9 mutants and 93-11 were constructed. Linkage analysis using two rcn F2 mapping populations with published simple sequence repeat markers demonstrated that the RCN8 and RCN9 genes were mapped on the long arm of chromosome 1 （119.6 cM） and the short arm of chromosome 6 （63.6 cM）, respectively. The results of the present study are beneficial to map-based cloning and functional analysis of the RCN8 and RCN9 genes.

关键词： gene-mapping reduced-culm-number rice simple sequence repeat marker.

Roussoelins A and B:two phenols with antioxidant capacity from ascidian-derived fungus Roussoella siamensis SYSU-MS4723

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Marine Life Science & Technology 2021年第1期3卷 69-76页

作者： Senhua Chen Hongjie Shen Yanlian Deng heng guo Minghua jiang Zhenger Wu Huimin Yin Lan Liu School of Marine Sciences Sun Yat-Sen UniversityGuangzhou 510006China School of Pharmacy Guangdong Medical UniversityDongguan 523808China Southern Laboratory of Ocean Science and Engineering(Guangdong Zhuhai)Zhuhai 519000China

Ascidian-derived microorganisms are a signifcant source of pharmacologically active metabolites with interesting structural *** discovering bioactive molecules from ascidian-derived fungi,two new phenols,roussoelins A(1)and B(2),and ten known polyketides(3–12)were isolated from the ascidian-derived fungus Roussoella siamensis *** planar structure of compounds 1 and 2 was established by analysis of HR-ESIMS and NMR *** conformational analysis of the new compounds was assigned according to coupling constants and selective gradient NOESY experiments,and absolute confgurations were completed by the modifed Mosher’s *** the isolated compounds,1,2,and 9 showed moderate antioxidant capacity.

关键词： Phenols Antioxidant capacity Ascidian-derived fungus Roussoella siamensis

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多尺度差分特征增强网络的遥感影像变化检测

计算机科学与探索 2025年第1期19卷 211-222页

作者：王杰蒋伏松蒋鹏上海海洋大学工程学院上海交通大学医学院附属第六人民医院内分泌代谢科上海交通大学医学院附属第六人民医院计算机中心

遥感影像变化检测旨在识别不同时期遥感影像中的目标差异，近年来基于卷积神经网络的方法在遥感影像变化检测任务中取得了很大进展。然而，受光照变化和季节更替的影响，不同时期遥感影像中的伪变化问题仍然难以解决。同时，大多方法中... 详细信息

遥感影像变化检测旨在识别不同时期遥感影像中的目标差异，近年来基于卷积神经网络的方法在遥感影像变化检测任务中取得了很大进展。然而，受光照变化和季节更替的影响，不同时期遥感影像中的伪变化问题仍然难以解决。同时，大多方法中未充分利用多尺度特征，导致模型的性能和准确率受到一定程度的限制。针对上述问题，提出一种多尺度差分特征增强的变化检测方法。利用由孪生网络编码器和差分网络编码器组成的并行编码框架分别提取不同层级的特征，将同级的双时特征和差分特征通过拼接的方式建立两者间的互补关系。引入差分特征增强模块获取更具判别性的特征图并将其作为差分网络编码器的补充输入，丰富变化信息的同时增加模型对变化区域的关注度，使其准确地区分地物的真实变化与伪变化。为了增强特征的多样性和表达能力，使用特征错位融合模块实现语义特征的交叉融合，让每个特征中的语义信息得到充分而不同的交互。该方法在CDD数据集和LEVIRCD数据集上的F1分数分别达到了95.45%和92.04%，交并比分别达到了92.26%和82.93%，与其余八种主流方法相比均为最优，实验结果证明了该方法的有效性。

关键词：遥感影像变化检测差分增强并行编码多尺度特征融合

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Experimental and molecular dynamics study of gas flow characteristics in nanopores

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Chinese Science Bulletin 2012年第13期57卷 1488-1493页

作者： LIU QiXin jiang PeiXue XIANG heng Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Beijing Key Laboratory of CO_(2)Utilization and Reduction TechnologyDepartment of Thermal EngineeringTsinghua UniversityBeijing 100084China

Gas flow characteristics in nanopores were investigated experimentally and numerically using molecular dynamics (MD) simulations with an emphasis on the friction factor and gas viscosity. The results show that the viscosity and the friction factor in nanopores are much lower than those in macroscale channels. The actual viscosities obtained from the MD studies showed that the gas viscosity in nanopores is less than the macroscale viscosity because collisions between gas molecules are less frequent in high Knudsen number flows and there are more collisions with the wall. The MD simulations show that the velocity profile is composed of two parts, with a much steeper velocity gradient near the wall.

关键词：气体流动特性分子动力学特性实验纳米孔 Knudsen数气体粘度数值模拟摩擦系数

中国特色高等教育话语体系的历史演进、核心要义与建构理路

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高校教育管理 2025年第1期19卷 84-98页

作者：姜嘉伟厦门大学教育研究院厦门大学教师发展中心福建厦门361005

中国特色高等教育话语体系本质上是一种坚持民族理想、推动国家治理、促进知识发展、开展对外交流的关系性实践。百年来,中国高等教育发展历经萌芽期、探索期、发展期和成长期,形成了以“救国”“革命”“改革”“复兴”为代表的高等教... 详细信息

中国特色高等教育话语体系本质上是一种坚持民族理想、推动国家治理、促进知识发展、开展对外交流的关系性实践。百年来,中国高等教育发展历经萌芽期、探索期、发展期和成长期,形成了以“救国”“革命”“改革”“复兴”为代表的高等教育话语体系。本土化是中国特色高等教育话语体系逐渐成形的关键线索,民族图像的大众化、国家权力的人民性、知识建构的自主性以及对外交流的平等性则在话语主体、话语权力、话语知识、话语秩序四个方面构成其核心要义。中国特色高等教育话语体系通过提升话语主体的民族自信、夯实话语意识形态的思想根基、提升高等教育的治理效能、激发话语知识的内生动力、重塑话语秩序的国际格局以推动中国高等教育本土化转型,不断形成具有中国现代性的高等教育理论与实践体系,全面增强中国特色高等教育话语体系的理论概括力、实践生命力、现实感召力和国际影响力。

关键词：中国特色话语体系高等教育话语体系本土化中国式现代化

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Phylogenetic conservatism in threatened species responses to climate change differs between functional types in the Gongga Mountains of China

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Journal of Mountain Science 2023年第12期20卷 3568-3581页

作者： ZU Kui-ling Nawal SHRESTHA jiang Yong JIA guo-qing PENG Shi-jia ZHU Xiang-yun WANG Zhi-heng Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNanchang 330045China Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education College of Urban and Environmental SciencesPeking UniversityBeijing 100871China State Key Laboratory of Plant Diversity and Specialty Crops Institute of BotanyChinese Academy of SciencesBeijing 100093China State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems College of EcologyLanzhou UniversityGansuLanzhou 730000China Administration of Gongga Mountain National Nature Reserve Kangding 626000China

Climate change has become one of the most critical threats to global ***,whether phylogenetically related species respond to climate change in similar ways remains *** answer to this question is crucial for understanding the impacts of climate change and the conservation on the tree of *** integrating species distribution models with a molecular phylogeny of 50 threatened plant species from one of the global biodiversity hotspots,Gongga Mountains(***)in southwest China,we evaluated the responses of threatened plant species to future climate change,and estimated whether species responses are phylogenetically *** reconstruction was used to calculate the phylogenetic distance and null model to verify the reliability of the *** found that correlations between responses of different species to future climate change decreased with the increase in their phylogenetic distance in the monocotyledonous or herbaceous species,but not in the dicotyledonous and woody *** results suggested that the responses of herbaceous and monocotyledonous threatened species in *** to future climate change tend to be phylogenetically conserved,while the responses of woody and dicotyledonous threatened species are *** study provides evidence for the existence of phylogenetically non-random extinction in the monocotyledonous herbs in *** and highlights the importance of integrating phylogenetic information and evolutionary history into conservation *** also provide theoretical basis and technical support for designing effective conservation schemes for the protection of biodiversity under anthropogenic climate change.

关键词： Conservation strategies Climate suitability Mountain plants Phylogenetic distance Species distribution models

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong Zhu Ruijie Liu jiang Ma Lina Hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning