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New chaotical image encryption algorithm based on Fisher–Yatess scrambling and DNA coding

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Chinese Physics B 2019年第4期28卷 121-130页

作者： Xing-Yuan Wang Jun-Jian Zhang Fu-Chen Zhang guang-hui cao School of Information Science and Technology Dalian Maritime University Faculty of Electronic Information and Electrical Engineering Dalian University of Technology College of Mathematics and Statistics Chongqing Technology and Business University School of Electronics & Information Engineering Liaoning University of Technology

Based on the Fisher–Yatess scrambling and DNA coding technology, a chaotical image encryption method is proposed. First, the SHA-3 algorithm is used to calculate the hash value of the initial password, which is used as the initial value of the chaotic system. Second, the chaotic sequence and Fisher–Yatess scrambling are used to scramble the plaintext,and a sorting scrambling algorithm is used for secondary scrambling. Then, the chaotic sequence and DNA coding rules are used to change the plaintext pixel values, which makes the ciphertext more random and resistant to attacks, and thus ensures that the encrypted ciphertext is more secure. Finally, we add plaintext statistics for pixel-level diffusion to ensure plaintext sensitivity. The experimental results and security analysis show that the new algorithm has a good encryption effect and speed, and can also resist common attacks.

关键词： Fisher–Yatess scrambling chaotic sequence DNA coding image encryption

Linking anisotropy with Fe_3C distribution in AISI 1045 steel

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1293-1303页

作者： Ke-chang Shen Gui-hua Li Yi-min Sun Yong-gang Wang Ying-jie Li guang-hui cao Wei-min Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University Shandong Institute of Metrology School of Materials Science and Engineering Shanghai University

The anisotropy of the microstructure, thermal expansion behavior, corrosion resistance and magnetic properties of AISI 1045 steel was investigated. The distribution of Fe3C lameUae in the investigation plane parallel to the radial directions of molds was observed to differ from that in the investigation plane perpendicular to the radial directions by transmission electron microscopy. The lattice constants a0 of α-Fe deduced from the XRD patterns of samples prepared using a sand （S）-mold and cut parallel to the radial direction of the mold （S//） and using a metal （M）-mold and cut parallel to the radial direction （M//）, the corrosion resistance measured using an electrochemical work- station, and the magnetic permeability obtained by vibrating sample magnetometry also indicated the existence of anisotropy in the tested samples. The anisotropic change of corrosion potential （Eeorr）, pitting potential （Epit） and magnetic permeability （μ） of the samples was observed to depend on the orientation factorF200 of α-Fe in the measured samples, which is controlled by the distribution of Fe3C lamellae in the eutectoid structure.

关键词： carbon steel microstructure anisotropy lattice constants

Unraveling brain aging through the lens of oral microbiota

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Neural Regeneration Research 2025年第7期20卷 1930-1943页

作者： Qinchao Hu Si Wang Weiqi Zhang Jing Qu guang-hui Liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijingChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijingChina University of Chinese Academy of Sciences BeijingChina Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijingChina Aging Biomarker Consortium BeijingChina State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Beijing Institute for Stem Cell and Regenerative Medicine BeijingChina

The oral cavity is a complex physiological community encompassing a wide range of *** of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative *** studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention *** this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and *** also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

关键词： Alzheimer's disease brain aging multiple sclerosis neurodegeneration neurodegenerative diseases oral microbiota Parkinson's disease periodontitis bacteria Porphyromonas gingivalis

Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-hui Zhang Zhi-Lai Zhan guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

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酚醛树脂对NBR性能的影响

特种橡胶制品 2017年第6期38卷 23-26页

作者：张志广谢竞慧曹政陈彦北株洲时代新材料科技股份有限公司湖南株洲412007

针对酚醛树脂(PF)改性后的丁腈橡胶(NBR)胶料进行了FT-IR分析、物理性能分析和动态力学性能分析。结果表明,NBR和PF发生了化学反应,生成了-O-醚键;随着PF用量从0份增加到50份,NBR/PF的硬度逐渐增大,拉断伸长率、热空气老化后的硬度变化... 详细信息

针对酚醛树脂(PF)改性后的丁腈橡胶(NBR)胶料进行了FT-IR分析、物理性能分析和动态力学性能分析。结果表明,NBR和PF发生了化学反应,生成了-O-醚键;随着PF用量从0份增加到50份,NBR/PF的硬度逐渐增大,拉断伸长率、热空气老化后的硬度变化、拉伸强度变化率、拉断伸长率变化率逐渐降低,拉伸强度、撕裂强度、回弹性和低温脆性温度先增大后减小,压缩永久变形和相对体积磨耗量先减小后增大,NBR/PF损耗因子(tanδ)的峰值逐渐降低,玻璃化转变温度(Tg)呈现向高温方向移动的趋势;当PF用量为50份时,NBR/PF的Tg比PF用量为30份时NBR/PF的Tg稍低。

关键词： NBR 酚醛树脂物理性能动态力学性能

中国式现代化对西方中心主义文明观的破题与超越

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保山学院学报 2025年第01期44卷 22-28页

作者：曹鏸中国农业大学马克思主义学院

从文明观的视角出发，中国式现代化代表着具有悠久历史传统的中华文明与马克思主义相结合，以全新形态进入当代人类文明体系中。中国式现代化从话语解构和范式升维两路径实现了西方中心主义文明观的现实批判，在复原现代化本真含义、打... 详细信息

从文明观的视角出发，中国式现代化代表着具有悠久历史传统的中华文明与马克思主义相结合，以全新形态进入当代人类文明体系中。中国式现代化从话语解构和范式升维两路径实现了西方中心主义文明观的现实批判，在复原现代化本真含义、打破消费主义幻境、回击话语启示陷阱三方面破解了西方中心主义文明观的现代化迷障，实现对资本逻辑和西方现代化模板的话语解构，并在“自我-他者-世界”三重向度上构成了对西方中心主义文明观发展范式、合作范式、文明范式的超越升华。

关键词：中国式现代化西方中心主义文明观现代化

Identification of sand and dust storm source areas in Iran

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Journal of Arid Land 2015年第5期7卷 567-578页

作者： cao hui LIU Jian WANG Guizhou YANG guang LUO Lei Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences International Ecosystem Management Partnership United Nations Environment Programme University of Chinese Academy of Sciences Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences

Sand and dust storms （SDS） are common phenomena in arid and semi-arid areas. In recent years, SDS frequencies and intensities have increased significantly in Iran. A research on SDS sources is important for understanding the mechanisms of dust generation and assessing its socio-economic and environmental impacts. In this paper, we developed a new approach to identify SDS source areas in Iran using a combination of nine related datasets, namely drought events, temperature, precipitation, location of sandy soils, SDS frequency, hu- man-induced soil degradation （HISD）, human influence index （HII）, rain use efficiency （RUE） and net primary pro- ductivity （NPP） loss. To identify SDS source areas, we firstly normalized these datasets under uniform criteria in- cluding layer reprojection using Lambert conformal conic projection, data conversion from shapefile to raster, Min-Max Normalization with data range from 0 to 1, and data interpolation by Kriging and images resampling （resolution of 1 km）. After that, a score map for the possibility of SDS sources was generated through overlaying multiple datasets under average weight allocation criterion, in which each item obtained weight equally. In the score map, the higher the score, the more possible a specific area could be regarded as SDS source area. Exceptions mostly came from large cities, like Tehran and Isfahan. As a result, final SDS source areas were mapped out, and Al-Howizeh/Al-Azim marshes and Sistan Basin were identified as main SDS source areas in Iran. The SDS source area in Al-Howizeh/Al-Azim marshes still keeps expanding. In addition, Al-Howizeh/Al-Azim marshes are now suf- fering rapid land degradation due to natural and human-induced factors and might totally vanish in the near future. Sistan Basin also demonstrates the impacts of soil degradation and wind erosion. With appropriate intensity, dura- tion, wind speed and altitude of the dust storms, sand particles uplifting from this area might have developed

关键词： sand and dust storm weight allocation criterion Kriging interpolation score map AI-Howizeh/AI-Azim marshes Sistan Basin

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： Jin-Peng Wang Guo-Cui Mao hui-Lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-cao （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

Unveiling pairing mechanism in quasi-one-dimensional Cr-based superconductors

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Science Bulletin 2017年第3期62卷 206-207页

作者： guang-Han cao Department of Physics Zhejiang University Hangzhou 310027 China

Superconductivity is a macroscopic quantum phenomenon in which electron pairing(or Cooper pairing)plays a crucial role for its *** Cooper pairing is mediated by electron-phonon interactions in most of simple metals and alloys which are widely called conventional *** are a few classes of superconductors,however,in which the electron pairing

关键词：电子配对超导体电子-声子相互作用准一维机制铬基 Cooper 量子现象