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Frontiers of Agricultural Science and Engineering 2017年第4期4卷 482-492页

作者： chao sun Meng LAI Shougong ZHANG Xiaomei sun Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Research Institute of ForestryChinese Academy of Forestry State Key Laboratory of Tree Genetics and Breeding Chinese Academy of Forestry Key Laboratory of Silviculture Co-Innovation Center of Jiangxi Typical Trees Cultivation and UtilizationCollege of Forestry Jiangxi Agricultural University

Wood properties are important traits that determine quality of structural wood. With the aim of performing efficient early selection for wood properties we investigated genetic variation in 20 Larix kaempferi clones aged from 4 to 15 years for four quality traits: wood density, wall thickness to lumen area, microfibrillar angle(MFA) and modulus of elasticity(MOE). We observed that age-related trends in overall means varied for differen traits: MFA decreased with the age, while the others generally increased with the age. Phenotypic variance always showed significant differences from the age of 8 years onward, with CVG ranging from 4% to 25%. Also clonal repeatability increased steadily until 9 years old and then kept medium or higher intensity(0.4–0.8). After the age of 6, genetic correlations were generally higher than phenotypic correlations. Estimates of early selection efficiency suggested that the optimal selection age for wood density was at age 5–6 years, while it was 9–10 years for the other traits. In combination with previous results we proposed a comprehensive early selection strategy for larch clonal breeding that involved selection based on nursery rooting ability, phenology, growth traits, and wood properties.

关键词： early selection genetic variation wood properties Silvi Scan Larix kaempferi

Microstructure, Interface, and Properties of Multilayered CrN/Cr_2O_3 Coatings Prepared by Arc Ion Plating

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Journal of Materials Science & Technology 2014年第12期30卷 1193-1201页

作者： Chang-Ming Shi Tie-Gang Wang Zhi-Liang Pei Jun Gong chao sun State Key Laboratory for Corrosion and Protection (SKLCP) Institute of Metal Research Chinese Academy of Sciences

There has been much interest in developing multilayered or nanolayered physical vapor deposition（PVD） coatings identified as a group of promising protective coatings for their excellent mechanical properties and corrosion resistance. In this study, the multilayered Cr N/Cr2O3 coatings with different bilayer periods（L） were synthesized on the polished high speed steel substrates from a Cr target with the alternative atmosphere of pure nitrogen and pure oxygen by arc ion plating（AIP） technique. The results revealed that the microstructure,morphologies and properties of the multilayered coatings were strongly influenced by the bilayer period（L）.There were two kinds of interfaces in the multilayered Cr N/Cr2O3coatings： the sharp ones and the blurry ones. With reducing the value of L, the macro-particles densities decreased gradually, whereas the coating microhardness, adhesive strength and wear resistance first increased, and then decreased slightly or remained stable as the bilayer period L 〈 590 nm. The multilayered Cr N/Cr2O3 coating with the bilayer period L of 590 nm possessed the best comprehensive properties, namely the highest microhardness, the strongest adhesion, and the lowest wear rate.

关键词： Cr2O3/CrN Multilayered coating Arc ion plating Interface Mechanical properties Wear

Thiophene-based conjugated microporous polymers:synthesis,characterization and efficient gas storage

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Science China Chemistry 2017年第8期60卷 1067-1074页

作者： chao-Jing sun Xue-Qian Zhao Peng-Fei Wang Hua Wang Bao-Hang Han CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoseience and Technology Beijing 100190 China

A series of thiophene-based conjugated microporous polymers （ThPOPs） have been synthesized on the basis of ferric chloride-catalyzed oxidative coupling polymerization of muRi-thienyl monomers. The structures of ThPOPs were confirmed via solid-state t3C CP/MAS NMR spectroscopy and Fourier-transform infrared spectroscopy. The ThPOPs possess high porosities and their high Brunauer-Emmett-Teller specific surface area results vary between 350 and 1320mZg . The presence of abundant ultra-micronores at 0.50-0.63 nm allows ThPOPs efficient gas （carbon dioxide, methane, and hydrogen） adsorption.

关键词： conjugated porous organic polymers thiophene gas adsorption oxidative polymerization

Core–shell nanostructure for supra-photothermal CO_(2)catalysis

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Rare Metals 2022年第5期41卷 1403-1405页

作者： chao-Yue sun Zhen-Wei Zhao Hong Liu Hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) University of JinanJinan 250022China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China

Powered by the solar light as energy source,gas-phase photothermal carbon dioxide(CO_(2)) catalysis has recently sprung up as a promising route to convert CO_(2) molecules into value-added chemicals,feedstocks,and fue... 详细信息

关键词： catalysis dioxide convert

Dust acoustic rogue waves of fractional-order model in dusty plasma

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Communications in Theoretical Physics 2020年第12期72卷 1-17页

作者： Jun-chao sun Zong-Guo Zhang Huan-He Dong Hong-Wei Yang College of Mathematics and System Science Shandong University of Science and TechnologyQingdao 266590China School of Mathematics Statistics Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

In this paper,the fractional-order model is used to study dust acoustic rogue waves in dusty ***,based on control equations,the multi-scale analysis and reduced perturbation method are used to derive the(3+1)-dimensional modified Kadomtsev–Petviashvili(MKP)***,using the semi-inverse method and the fractional variation principle,the(3+1)-dimensional time-fractional modified Kadomtsev–Petviashvili(TF-MKP)equation is ***,the Riemann–Liouville fractional derivative is used to study the symmetric property and conservation laws of the(3+1)-dimensional TF-MKP ***,the exact solution of the(3+1)-dimensional TF-MKP equation is obtained by using fractional order transformations and the definition and properties of Bell *** on the obtained solution,we analyze and discuss dust acoustic rogue waves in dusty plasma.

关键词： time-fractional modified Kadomtsev–Petviashvili equation conservation laws dust acoustic rogue waves

Networked Control System Time Delay Compensation Based on Improved Implicit GPC 36

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Networked Control System Time Delay Compensation Based on Im...

Facile One-Pot Synthesis of ZSM-5 Aggregates with Interand Intra-Crystalline Mesopores for Methanol to Gasoline Conversion

第36届中国控制会议

作者： sun chao Zhou Ying Dai Junxiang Lin Jinxing Nanjing University of Posts and Telecommunications College of Automation

ISBN: (纸本)9781538629185

The ELM is used to predict the delay,and combines with implicit generalized predictive control（IGPC） to compensate time delay in this *** random time-delay in the networked control system（NCS） can usually deteriorate the control performance and stability of networked control *** order to solve this problem,this paper puts forward the networked time delay in a short time based on extreme learning machine（ELM）.At the same time,IGPC is used in this networked control system with the results of *** simulation results show that the method in this paper make the output of the system track the reference trajectory well and performance better than traditional generalized prediction algorithm.

关键词： networked control system implicit generalized prediction algorithm extreme learning machine time delay compensation

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Transactions of Tianjin University 2019年第1期25卷 9-22页

作者： Yaquan Wang Chunyang Fan Hongyao Li Xiao Wang Fanjun Meng chao sun Liying sun Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University

ZSM-5 aggregates consisting of superfine and hierarchical nanocrystals(combined with micropores and intra-crystalline mesopores) with an average size of 30 nm were prepared through one-pot synthesis with the assistance of anionic polyacrylamide(APAM). The resultant zeolites(AHN-ZSM-5) were characterized by XRD, ICP-OES, SEM, TEM, BET, NH_3-TPD, Py-IR, and TG analyses and evaluated in the methanol to gasoline(MTG) reaction. Characterization results show that the hierarchical ZSM-5 aggregates possessed two kinds of mesopores, namely inter-and intra-crystalline mesopores. The amount of APAM considerably influenced the mesoporosity and textural properties of AHN-ZSM-5 zeolites. With the addition of APAM in the synthesis, the AHN-ZSM-5 zeolites exhibited large mesopore volume, large external surface area, and appropriate acidity. When applied in the MTG reaction, AHN-ZSM-5 demonstrated a catalytic lifetime that was 1.6 times longer than that of conventional ZSM-5 synthesized in the absence of APAM.

关键词： Hierarchical nanocrystal Intra-crystalline mesopore ZSM-5 aggregate Anionic polyacrylamide Methanol to gasoline

Sustainable Nutrient Management in Chinese Agriculture: Challenges and Perspective

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Pedosphere 2006年第2期16卷 253-263页

作者： GAO chao sun Bo ZHANG Tao-Lin Department of Geography Nanjing University Nanjing 210093 （China）. Institute of Soil Science Chinese Academy of Sciences Nanjing 2100（78 （China）

China has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. Sustainable soil nutrient management is of paramount importance to the world's most populous country. Critical challenges the country is facing in sustaining soil fertility and in alleviating the hazardous impact of intensive fertilizer use are discussed in this paper. It is emphatically pointed out that national strategies as well as area-specific action plans with respect to scientific nutrient management are urgently needed to balance productivity and sustainability in the future. Relevant proposals for addressing those challenges are also presented.

关键词： China food security nutrient management soil fertility water quality

Spatiotemporal dynamics of the urban sprawl in a typical urban agglomeration： a case study on Southern Jiangsu, China （1983-2007）

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Frontiers of Earth Science 2014年第4期8卷 490-504页

作者： Yongxue LIU Jieli CHEN Wangyu CHENG chao sun Saishuai ZHAO Yingxia PU School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China Changzhou Land and Resources Administration Wujin District Branch Changzhou 213161 China

China has experienced urbanization at an unprecedented rate over the past decades. Against this background, this paper demonstrates the multi-level spatiotemporal urban sprawl process from 1983 to 2007 on the perspective of urban agglomeration with a case study in Southern Jiangsu. Based on a combination of eight rounds of satellite images from 1983 to 2007, the presented results suggest the following three main findings：（1） At the prefecture-city level, the urban sprawl in Southern Jiangsu has presented significantly divergent growth patterns, with more than half of this vast growth occurring in the Suzhou prefecture-level city. （2） At the county level, clear spatial differentiations exist in the direction of the urban sprawl. The centroids of all county seats in the Suzhou and Wuxi prefecture-level cities have an eastward tendency （Shanghai oriented）, while those of the county seats in the Changzhou prefecture-level city tend to be westward （Nanjing oriented）. （3） At the township level, two convergent groups have gradually formed over time; namely, the low density urban zone in the western hilly land and the high density urban zone around the three central downtown areas. The urban areas close to urban cores tend to merge, showing a high-density convergent growth pattern, as do the western and southwestern townships in Southern Jiangsu, showing a low-density convergent growth pattern. All of these findings may be valuable for researchers and local authorities in providing reference for regional coordinated growth, environmental management, and urban planning decision-making.

关键词： Southem Jiangsu urban sprawl spatiotemporal dynamics rapid urbanization areas