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Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-Feng Yang Hai-Feng Song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability TCP phases Thermodynamic properties W–Re alloy

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials science) 2025年第1期40卷 246-257页

作者： ZHANG Jian NIE Wei HUANG Jin ZHU Ke LIU Ruxia ZHANG Ruizhi LUO Guoqiang SHEN Qiang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

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Epigenetics in the modern era of crop improvements

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science China life sciences 2025年

作者： Yan Xue Xiaofeng Cao Xiangsong Chen Xian Deng Xingwang Deng Yong Ding Aiwu Dong Chengguo Duan Xiaofeng Fang Lei Gong Zhizhong Gong Xiaofeng Gu Chongsheng He Hang He Shengbo He Xinjian He Yan He Yuehui He Guifang Jia Danhua Jiang Jianjun Jiang Jinsheng Lai Zhaobo Lang Chenlong Li Qing Li Xingwang Li Bao Liu Bing Liu Xiao Luo Yijun Qi Weiqiang Qian Guodong Ren Qingxin Song Xianwei Song Zhixi Tian Jiawei Wang Yuan Wang Liang Wu Zhe Wu Rui Xia Jun Xiao Lin Xu Zhengyi Xu Wenhao Yan Hongchun Yang Jixian Zhai Yijing Zhang Yusheng Zhao Xuehua Zhong Daoxiu Zhou Ming Zhou Yue Zhou Bo Zhu Jiankang Zhu Qikun Liu College of life sciences Institute of Life Science and Green Development Hebei University Biotechnology Research institute Chinese Academy of Agricultural Sciences College of Biology Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation Hunan Engineering and Technology Research Center of Hybrid Rapeseed Hunan University institute of Advanced Agricultural sciences School of Advanced Agricultural Sciences Peking University State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural University National institute of Biological sciences Key Laboratory of Seed Innovation Institute of Genetics and Developmental Biology Chinese Academy of Sciences School of Advanced Agricultural sciences Peking-Tsinghua Center for Life Sciences Peking University Synthetic and Functional Biomolecules Center Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Key Laboratory of Seed Innovation State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences State Key Laboratory of Wheat Improvement Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agricultural Sciences in Weifang State Key Laboratory of Crop Stress Adaptation and Improvement School of Life Sciences Henan University State Key Laboratory of Maize Bio-breeding National Maize Improvement Center Department of Plant Genetics and Breeding China Agricultural University Frontiers science Center for Molecular Design Breeding China Agricultural University Center for Crop Functional Genomics and Molecular Breeding China Agricultural University Sanya institute of China Agricultural University Hainan Yazhou Bay Seed Laboratory institute of Advan

Epigenetic mechanisms are integral to plant growth, development, and adaptation to environmental stimuli. Over the past two decades,our comprehension of these complex regulatory processes has expanded remarkably, producing a substantial body of knowledge on both locus-specific mechanisms and genome-wide regulatory patterns. Studies initially grounded in the model plant Arabidopsis have been broadened to encompass a diverse array of crop species, revealing the multifaceted roles of epigenetics in physiological and agronomic traits. With recent technological advancements, epigenetic regulations at the single-cell level and at the large-scale population level are emerging as new focuses. This review offers an in-depth synthesis of the diverse epigenetic regulations, detailing the catalytic machinery and regulatory functions. It delves into the intricate interplay among various epigenetic elements and their collective influence on the modulation of crop traits. Furthermore, it examines recent breakthroughs in technologies for epigenetic modifications and their integration into strategies for crop improvement. The review underscores the transformative potential of epigenetic strategies in bolstering crop performance, advocating for the development of efficient tools to fully exploit the agricultural benefits of epigenetic insights.

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Research status and prospects of the fractal analysis of metal material surfaces and interfaces

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 20-38页

作者： Qinjin Dai Xuefeng Liu Xin Ma Shaojie Tian Qinghe Cui Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China School of Mechanical and Electrical Engineering Xinjiang Institute of EngineeringUrumqi 830023China

As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine *** analysis has been used to characterize the shapes of metal materials at various scales and *** methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and ***,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal *** the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear *** relationship between the fractal dimensions and properties of metal material surfaces and interfaces is *** from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be *** is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.

关键词： metal material surfaces and interfaces fractal analysis fractal dimension homogeneity

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Genes and proteins expressed at different life cycle stages in the model protist Euplotes vannus revealed by both transcriptomic and proteomic approaches

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science China life sciences 2025年第1期68卷 232-248页

作者： Yaohan Jiang Xiao Chen Chundi Wang Liping Lyu Saleh A.Al-Farraj Naomi A.Stover Feng Gao Key Laboratory of Evolution & Marine Biodiversity (Ministry of Education) and institute of Evolution & Marine Biodiversity Ocean University of China Marine College Shandong University Zoology Department College of ScienceKing Saud University Department of Biology Bradley University Laboratory for Marine Biology and Biotechnology Qingdao Marine Science and Technology Center

Sexual reproduction first appeared in unicellular protists and has continued to be an essential biological process in almost all *** protists, which contain both germline and somatic genomes within a single cell, have evolved a special form of sexual reproduction called conjugation that involves mitosis, meiosis, fertilization, nuclear differentiation, genome rearrangement, and the development of unique cellular structures. The molecular basis and mechanisms of conjugation vary dramatically among ciliates, and many details of the process and its regulation are still largely unknown. In order to better comprehend these processes and mechanisms from an evolutionary perspective, this study provides the first comprehensive overview of the transcriptome and proteome profiles during the entire life cycle of the newly-established marine model ciliate Euplotes vannus. Transcriptome analyses from 14 life cycle stages(three vegetative stages and 11 sexual stages) revealed over 26,000 genes that are specifically expressed at different stages, many of which are related to DNA replication,transcription, translation, mitosis, meiosis, nuclear differentiation, and/or genome rearrangement. Quantitative proteomic analyses identified 338 proteins with homologs associated with conjugation and/or somatic nuclear development in other ciliates, including dicer-like proteins, Hsp90 proteins, RNA polymerase Ⅱ and transcription elongation factors, ribosomal-associated proteins, and ubiquitin-related proteins. Four of these homologs belong to the PIWI family, each with different expression patterns identified and confirmed by RT-qPCR,which may function in small RNA-mediated genome rearrangement. Proteins involved in the nonhomologous end-joining pathway are induced early during meiosis and accumulate in the developing new somatic nucleus, where more than 80% of the germline sequences are eliminated from the somatic genome. A number of new candidate genes and proteins likely t

关键词： sexual reproduction transcriptomic proteomic genome rearrangement PIWI NHEJ

Constraints on holographic QCD phase transitions from PTA observations

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical science and Technology Ningbo University Max Planck institute for Gravitational Physics (Albert Einstein institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Bifunctional bridging capping layer enables 24.5% efficiency of perovskite solar cells with polymer-based hole transport materials

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science China Chemistry 2025年第1期68卷 350-359页

作者： Can Zhu Yiyang Wang Lei Meng Beibei Qiu Jing Li Shucheng Qin Ke Hu Xin Jiang Wenbin Lai Minchao Liu Zhe Liu Chenxing Lu Jinyuan Zhang Yongfang Li Beijing National Laboratory for Molecular sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences School of Chemical science University of Chinese Academy of Sciences Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province College of Physics and Electronic Information Engineering Zhejiang Normal University Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of Sciences Laboratory of Advanced Optoelectronic Materials College of Chemistry Chemical Engineering and Materials ScienceSoochow University

Developing a bridge capping layer between perovskite and hole transport layer materials（HTMs） in the n-i-p perovskite solar cells（pero-SCs） is an effective approach to modify the morphology of HTMs and passivate the perovskite ***, we select the quinoxaline-based bifunctional passivation agent, quinoxalin-6-yl-methylamine hydrochloride（Qx MACl）,as the bridging layer, and a D-A copolymer PBQ12 containing the same quinoxaline unit as an HTM for the n-i-p pero-SCs. Due to the π-π stacking among the common quinoxaline units in the bridge layer and HTM, Qx MACl induces the π-π stacking of the PBQ12 film and improves the film morphology of HTMs with better conductivity. Additionally, Qx MACl can effectively passivate the perovskite surface, and PBQ12 possesses appropriate energy levels and high hole mobility. The pero-SCs based on FAPbI3with PBQ12/Qx MACl treatment showed a higher power conversion efficiency（PCE） of 24.05% and outstanding stability, maintaining 95.4% and 92.1% of its initial PCE after 750 h of storage and after over 800 h of thermal annealing at 85 °C, respectively. To further enhance the PCE of the PBQ12/Qx MACl-based devices, we developed a non-metal ion dopant for the PBQ12 HTM. Through trace doping of PBQ12 HTM by the non-metal ion dopant, the PCE of the PBQ12/Qx MACl-based devices reached 25.24%（the calibrated PCE of 24.55% by the National institute of Metrology, China）.

关键词： D-A copolymer, hole transport materials, bifunctional bridge capping layer, passivation perovskite solar cells

Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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science China Earth sciences 2025年第1期68卷 111-127页

作者： Zhi-Wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG Qing XIA Xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine science and Engineering Guangdong Laboratory (Guangzhou) State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Traffic & Transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service

Multi-Stage-Based Siamese Neural Network for Seal Image Recognition

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Computer Modeling in Engineering & sciences 2025年第1期142卷 405-423页

作者： Jianfeng Lu Xiangye Huang Caijin Li Renlin Xin Shanqing Zhang Mahmoud Emam School of Computer science and Technology Hangzhou Dianzi UniversityHangzhou310018China Shangyu institute of science and Engineering Hangzhou Dianzi UniversityShaoxing312300China Faculty of Artificial Intelligence Menoufia UniversityShebin El-Koom32511Egypt

Seal authentication is an important task for verifying the authenticity of stamped seals used in various domains to protect legal documents from tampering and *** seal inspection is commonly audited manually to ensure document ***,manual assessment of seal images is tedious and laborintensive due to human errors,inconsistent placement,and completeness of the *** image recognition systems are inadequate enough to identify seal types accurately,necessitating a neural network-based method for seal image ***,neural network-based classification algorithms,such as Residual Networks(ResNet)andVisualGeometryGroup with 16 layers(VGG16)yield suboptimal recognition rates on stamp ***,the fixed training data categories make handling new categories to be a challenging *** paper proposes amulti-stage seal recognition algorithmbased on Siamese network to overcome these ***,the seal image is pre-processed by applying an image rotation correction module based on Histogram of Oriented Gradients(HOG).Secondly,the similarity between input seal image pairs is measured by utilizing a similarity comparison module based on the Siamese ***,we compare the results with the pre-stored standard seal template images in the database to obtain the seal *** evaluate the performance of the proposed method,we further create a new seal image dataset that contains two subsets with 210,000 valid labeled pairs in *** proposed work has a practical significance in industries where automatic seal authentication is essential as in legal,financial,and governmental sectors,where automatic seal recognition can enhance document security and streamline validation ***,the experimental results show that the proposed multi-stage method for seal image recognition outperforms state-of-the-art methods on the two established datasets.

关键词： Seal recognition seal authentication document tampering siamese network spatial transformer network similarity comparison network