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Investigation of Instability in Self-pumped Ce:KNSBN Crystal

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光电子·激光 1998年第1期 75-77页

作者： liu jifang yun zhisheng li yulin (Xian Institute of Optics and Precision Mechanics Academia Sinica,Xian 710068)

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关键词： self pump phase conjugate wave reflectivity temporal intensity evolution unstable phase conjugate wave

Analysis of intron sequence variability of the conservative HMG-box of Sox9 genes in allotetraploids and their original parents

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Progress in Natural Science:Materials International 2007年第5期17卷 537-543页

作者： liu jifang, liu Shaojun , Tao Min, li Wei and liu yun (Key Laboratory of Protein Chemistry and Developmental Biology of State Education Ministry of China, College of life Sciences, Hunan Normal University, Changsha 410081, China) Key Lab. of Protein Chemistry and Developmental Biology MOE College of Life Sciences Hunan Normal University Changsha 410081 China

The Sox genes of allotetraploids and their original maternal red crucian carp (Carassius caassius red var.) and original paternal common carp (Cyprinus carpio L.) were detected by PCR with the designed primers based on the conserved HMG-box sequence in different species. Sequencing of Sox genes indicated that two Sox9 genes (Atsox9a and Atsox9b) existed in allotetraploids, while only one Sox9 gene existed in red crucian carp (Rcsox9a) and common carp (Ccsox9b) . All of the four Sox9 genes contained an intron in the HMG-box. with the sizes of 413 bp, 703 bp, 401 bp and 714 bp, respectively. Moreover, the introns obeyed the rule of "GT-AG" . A high similarity was observed between introns of Atsox9a and Rcsox9a (94.4%), Atsox9b and Ccsox9b (97.8%). Interestingly, the deduced amino acid sequences of their corresponding exons all shared 100% identity. Thus, introns of the HMG-domain of Sox9s in allotetraploids and their original parents have not only the length polymorphism but also intron variability. Our results provide significant molecular evidence for the origin and evolution of allotetraploids.

关键词： Sox9 intron genetic variability phylogenesis.

Electrochemical behavior of open-cellular structured Ti-6Al-4V alloy fabricated by electron beam melting in simulated physiological fluid:the significance of pore characteristics

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Journal of Materials Science & Technology 2022年第2期97卷 272-282页

作者： Xin Gai Rui liu yun Bai Shujun li Yang Yang Shenru Wang Jianguo Zhang Wentao Hou yulin Hao Xing Zhang Rui Yang R.D.K.Misra Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Orthopedic Surgery Peking Union Medical College Hospital(PUMCH)Peking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China Department of Metallurgical Materialsand Biomedical EngineeringThe University of Texas at El Paso500W.University AvenueEl PasoTX 79968United States

The cellular structured titanium alloys have attracted significant attention for implants because of their lower Young’s modulus,which is comparable to human bone and has the capability of providing space for bone tissue ***,there is a gap in the knowledge in regard to the relationship between the pore characteristics and the electrochemical performance of open-cellular structured titanium *** this study,we elucidate the influence of pore characteristics on the electrochemical performance of open-cellular structured Ti-6Al-4V alloys produced by electron beam melting(EBM).Intriguingly,the passive film formed on cellular structured Ti-6Al-4V alloy with a larger pore size was more stable and protective,and the corrosion performance was superior compared to the samples with a smaller pore size in phosphate buffered saline(PBS),mainly because of relatively smaller exposed surface area and unlimited flow of ***,in acidic PBS containing fluoride ions,the pore characteristics did not play an important role in the corrosion *** was considered that the protective film breaks down such that the corrosion performance of cellular structured alloys was comparable to each other in this harsh environment.

关键词： Cellular structure Ti-6Al-4V Electron beam melting Corrosion resistance Fluoride ion

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MICROSTRUCTURE AND MECHANICAL PROPERTIES OF 8090 Al-li ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第2期5卷 89-94页

作者： liu yulin ZHANG yun ZHAO Hong’en HU Zhuangqi SHI Changxu Institute of Metal Research,Academia Sinica,Shentang,China Institute of Metal Research Academia Sinica Shenyang China

The change of mechanical properties of the 8090 Al-li alloy influenced by aging is attributed to the change of δ′-phase particle size and the precipitation of S′-*** δ′-phase may easily precipitate and rapidly grow,but the S′-phase can only precipitate with a longer stage of *** precipitation of S′-phase would be promoted by cold working prior to ag- *** co-precipitation of δ′- and S′-phase could improve the strength and plastieity of the alloy,for which aging at 190℃.for 20—30 h seems to be *** addition,the precipitate free zone( PFZ)can form at high angle grain boundary and its width is over 200 nm in peak aging *** at sub-grain boundary,the formation of PFZ is difficult.

关键词： Al-li alloy aging microstructure mechanical properties

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Remote sensing of subtropical tree diversity:The underappreciated roles of the practical definition of forest canopy and phenological variation

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Forest Ecosystems 2023年第3期10卷 378-386页

作者： Yongchao liu Ruyun Zhang Chen-Feng lin Zhaochen Zhang Ran Zhang Kankan Shang Mingshui Zhao Jingyue Huang Xiaoning Wang You li yulin Zeng yun-Peng Zhao Jian Zhang Dingliang Xing Zhoushan Archipelago Observation and Research Station Institute of Eco-Chongming(IEC)Zhejiang Tiantong Forest Ecosystem National Observation Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai200241China Systematic&Evolutionary Botany and Biodiversity Group MOE Key Laboratory of Biosystems Homeostasis&ProtectionCollege of Life SciencesZhejiang UniversityHangzhou310058China Shanghai Chenshan Botanical Garden Shanghai201602China Tianmushan National Nature Reserve Management Bureau Hangzhou311311China

Tree species diversity is vital for maintaining ecosystem functions,yet our ability to map the distribution of tree diversity is limited due to difficulties in traditional field-based *** developments in spaceborne remote sensing provide unprecedented opportunities to map and monitor tree diversity more *** we built partial least squares regression models using the multispectral surface reflectance acquired by Sentinel-2 satellites and the inventory data from 74 subtropical forest plots to predict canopy tree diversity in a national natural reserve in eastern *** particular,we evaluated the underappreciated roles of the practical definition of forest canopy and phenological variation in predicting tree diversity by testing three different definitions of canopy trees and comparing models built using satellite imagery of different *** best models explained 42%–63%variations in observed diversities in cross-validation tests,with higher explanation power for diversity indices that are more sensitive to abundant *** models built using imageries from early spring and late autumn showed consistently better fits than those built using data from other seasons,highlighting the significant role of transitional phenology in remotely sensing plant *** results suggested that the cumulative diameter(60%–80%)of the biggest trees is a better way to define the canopy layer than using the subjective fixeddiameter-threshold(5–12 cm)or the cumulative basal area(90%–95%)of the biggest ***,these approaches resulted in contrasting diversity maps that call attention to canopy structure in remote sensing of tree *** study demonstrates the potential of mapping and monitoring tree diversity using the Sentinal-2 data in species-rich forests.

关键词： Canopy structure Multispectral remote sensing Seasonal phenology Subtropical forest Tree species diversity

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