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Effects of site conditions on growth and wood properties of Populus×euramericana cv.'74/76'

Journal of Forestry Research 2023年第2期34卷 401-414页

作者： Jianmin Fan Changjun Ding Shijie Wang Changming Ma Chao Zhang Yongtan Li Jinmao Wang Minsheng Yang Xiaohua su Forest Department Forestry CollegeHebei Agricultural UniversityBaoding 071000People’s Republic of China Research Institute of Forestry Chinese Academy of ForestryBeijing 100091People’s Republic of China Hebei Key Laboratory for Tree Genetic Resources and Forest Protection Baoding 071000People’s Republic of China Forestry College Hebei Agricultural UniversityBaoding 071000People’s Republic of China

The growth and wood properties of 240 individual Populus×euramericana cv.’74/76’(hereafter poplar 107)trees planted in Hebei Plain,China was *** annual increments in height,breast height diameter and volume,as well as cellulose,hemicellulose and lignin contents,shrinkage,density,bending strength and modulus of elasticity in the heart wood and sap *** factors influencing growth and wood properties were analyzed using correlation and stepwise regres *** results show that the coefficients of variation(CVs)of growth traits ranged from 10.6 to 22.4%.The CVs of the chemical properties of heartwood ranged from 4.3 to 30.2%,and for sap wood from 3.2 to 27.5%.The CVs of the physical and mechanical properties of heartwood ranged from 8.6 to 31.7%,and for sapwood from 6.4 to 29.9%.The results of one-way ANOVA showed that there were significant differences in growth traits and wood properties among *** pH,total and available phosphorus,total potassium,and soil organic matter were key soil factors affecting growth and wood properties of poplar 107,whereas mean annual ground temperatures and precipitation were the main climatic *** better cultivate poplar 107,area with less annual rainfall,slightly higher temperature and soil pH value close to neutral should be selected.

关键词： Poplar clone Environmental factors Growth Wood density Mechanical properties Wood chemical composition

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Exploring the impact of Nafion modifier on electrocatalytic CO_(2) reduction over Cu catalyst

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Journal of Energy Chemistry 2024年第1期88卷 543-551,I0012页

作者： Yingshi su Yonghui Cheng Zhen Li Yanjia Cui Caili Yang Ziyi Zhong Yibing Song Gongwei Wang Lin Zhuang College of Chemistry&Chemical Engineering and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou UniversityShantou 515063GuangdongChina College of Chemistry and Molecular Sciences Hubei Key Lab of Electrochemical Power SourcesWuhan UniversityWuhan 430072HubeiChina The Institute for Advanced Studies Wuhan UniversityWuhan 430072HubeiChina Department of Chemistry Engineering Guangdong Technion-Israel Institute of Technology(GTIIT)Shantou 515063GuangdongChina Technion-Israel Institute of Technology(IIT) Haifa 32000Israel

Nafion as a universal polymer ionomer was widely applied for nanocatalysts electrode ***,the effect of Nafion on electrocatalytic performance was often overlooked,especially for CO_(2)***,the key roles of Nafion for CO_(2)RR were systematically studied on Cu nanoparticles(NPs)*** found that Nafion modifier not only inhibit hydrogen evolution reaction(HER)by decreasing the accessibility of H_(2)O from electrolyte to Cu NPs,and increase the CO_(2)concentration at electrocatalyst interface for enhancing the CO_(2)mass transfer process,but also activate CO_(2)molecule by Lewis acid-base interaction between Nafion and CO_(2)to accelerate the formation of^(*)CO,which favor of C–C coupling for boosting C_(2)product *** to these features,the HER selectivity was suppressed from 40.6%to 16.8%on optimal Cu@Nafion electrode at-1.2 V versus reversible hydrogen electrode(RHE),and as high as 73.5%faradaic efficiencies(FEs)of C_(2)products were achieved at the same applied potential,which was 2.6 times higher than that on bare Cu electrode(~28.3%).In addition,Nafion also contributed to the long-term stability by hinder Cu NPs morphology ***,this work provides insights into the impact of Nafion on electrocatalytic CO_(2)RR performance.

关键词： Nafion modifier CO_(2)reduction Cu nanoparticles In situ ATR-SEIRAS C_(2)product

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Predictions for production of superheavy nuclei with Z=105–112 in hot fusion reactions

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Nuclear Science and Techniques 2018年第11期29卷 166-173页

作者： Xiao-Bin Yu Long Zhu Zhi-Han Wu Fan Li Jun su Chen-Chen Guo Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

Abstract The effects of mass asymmetry on the production of superheavy nuclei(SHN),within the dinuclear system model,are investigated in this *** is observed that the fusion probability decreases with decreasing mass asymmetry.A total of 192 possible combinations of projectiles from O to Ti and targets with half-lives longer than30 days for producing SHN^(264)Db,^(265)Db,^(267)Sg,^(268)Bh,268Sg,^(269)Bh,^(271)Hs,^(271)Mt,^(272)Hs,^(272)Mt,^(273)Mt,^(274)Ds,275Ds,^(275)Rg,^(276)Ds,^(276)Rg,^(277)Rg,^(278)Cn,^(279)Cn,and^(280)Cn are ***,the optimal combinations and incident energies for synthesizing these nuclei are *** of the cross sections for production of SHNare larger than 10 pb;therefore,the process can be carried out with the available experimental equipment.

关键词： DNS model Systematic study Fusion reaction superheavy nuclei Evaporation residue cross section

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Potential role of Th17 cells in the pathogenesis of inflammatory bowel disease

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World Journal of Gastroenterology 2009年第46期15卷 5784-5788页

作者： Zhan-Ju Liu Praveen K Yadav Jing-Ling su Jun-Shan Wang Ke Fei Department of Gastroenteroiogy Shanghai Tenth People'sHospital Tongji University Shanghai 200072 China Department of Thoracic surgery Shanghai TenthPeople's Hospital Tongji University Shanghai 200072 China

The etiopathology of inflammatory bowel disease （IBD） remains elusive. Accumulating evidence suggests that the abnormality of innate and adaptive immunity responses plays an important role in intestinal inflam- mation. IBD including Crohn＇s disease （CD） and ulcerative colitis （UC） is a chronic inflammatory disease of the gastrointestinal tract, which is implicated in an inappropriate and overactive mucosal immune response to luminal flora. Traditionally, CD is regarded as a Thl- mediated inflammatory disorder while UC is regarded as a Th2-1ike disease. Recently, Th17 cells were identified as a new subset of T helper cells unrelated to Thl or Th2 cells, and several cytokines [e.g. interleukin （IL）-21, IL-23] are involved in regulating their activation and differentiation. They not only play an important role in host defense against extracellular pathogens, but are also associated with the development of autoimmunity and inflammatory response such as IBD. The identification of Th17 cells helps us to explain some of the anomalies seen in the Thl/Th2 axis and has broadened our understanding of the immunopathological effects of Th17 cells in the development of IBD.

关键词： Crohn's disease Inflammatory bowel disease Interleukin-17 Interleukin-23 Th17 cells Ulcerative colitis

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Rutile in HP Rocks from the Western Tianshan,China:Mineralogy and Its Economic Implications

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Journal of Earth Science 2018年第5期29卷 1049-1059页

作者： Wen su Jilei Li Qian Mao Jun Gao Xin Liu Fei Chen Xiao-Mei Ge State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Beijing Institute of Geology for Mineral Resources Beijing 100012China

Rutile is a common Ti-bearing accessory mineral in high pressure （HP） metamorphic rocks of the western Tianshan. Distribution of rutile in the HP rocks varies from 0.5% in the greenschist to 30% in the rutile-bearing vein. Rutile can be subdivided into three groups based on the variation of trace elements： The first group has an averaged Zr content of 18 ppm-44 ppm and Hf content of 0.8 ppm-2.4 ppm, which correspond to occurrence of rutile from vein; the second group Zr of 59 ppm-63 ppm, Hf of 3.5 ppm-3.7 ppm; and the third group Zr of 150 ppm-160 ppm and Hf of 3.9 ppm, corresponding to rutile in the matrix of blueschist and eclogite, respectively. Rutile has been retrograded to ilmenite and titanite partly or completely, reducing the value of the ore. But rutile of HP rocks in the western Tianshan usually has the lowest content of uranium （〈1 ppm U）, which might become an attractive raw material for the Ti industry. Therefore, rutile-bearing HP rocks in the western Tianshan as a mineral resource will be the focus of considerable attention.

关键词： Ti resource rutile HP vein eclogite western Tianshan.

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Performance optimization for high speed axial piston pump considering cylinder block tilt

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Chinese Journal of Aeronautics 2023年第9期36卷 437-450页

作者： Haogong XU Junhui ZHANG Shoujun ZHAO Junyuan CHEN Weidi HUANG Xiaochen HUANG Fei LYU Qi su Bing XU State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China Beijing Institute of Precision Mechatronics and Controls Beijing 100076China Jiangsu Jinling Intelligent Manufacturing Research Institute Co LtdNanjing 210006China

Increasing the rotating speed is considered as an efficient approach to upgrade the power-to-weight ratio in an axial piston pump,but penalized by more leakage and more severe wear resulting from the adverse cylinder block *** studies mainly focused on the bearing characteristic of the valve plate/cylinder block pair,but the spline coupling also plays a key role in the undesired cylinder block tilt,which has been little studied.A theoretical model for the rotating assembly is presented to investigate the effect of the spline coupling length on the cylinder block tilt and the performance of the valve plate/cylinder block pair.A typical high-speed axial piston pump with the displacement of 5.2 mL/r at 10000 r/min was studied by simulation and *** shows that the optimal spline coupling length is one value increased by 2 mm from the original,bringing a remarkable leakage reduction under the high-speed condition by decreasing the cylinder block tilting *** experiment result matches well with the *** influences of the spline coupling on the cylinder block tilt and the leakage were demonstrated.

关键词： Cylinder block tilt High-speed axial piston pump Leakage Spline coupling Wear

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Friction compensation for an m-Level telescope based on high-precision LuGre parameters identification

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Research in Astronomy and Astrophysics 2021年第1期21卷 185-197页

作者： Yan-Rui su Qiang Wang Fa-Bao Yan Yong-Mei Huang School of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209China Laboratory for ElectromAgnetic Detection Institute of Space SciencesShandong UniversityWeihai 264209China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China

Friction torque severely weakens the tracking accuracy and low-speed stability of an m-level TCS(telescope control system).To solve this problem,a friction compensation method is proposed,based on high-precision LuGre friction model parameters *** with dynamometer calibration,we first design a DOB(disturbance observer)to acquire high-accuracy TCS friction value in real ***,the PSO-GA(a hybrid algorithm combined particle swarm optimization algorithm and genetic algorithm)optimization algorithm proposed effectively and efficiently realizes the LuGre model parameters *** addition,we design a TCS controller including DOB and LuGre model parameters identification based on double-loop PID controller for practical *** verification tests indicate that the accuracy of DOB calibrated can reach 96.94%of the real measured *** azimuth axis operates in the speed cross-zero work mode,the average positive peak to tracking error reduces from 0.8926"to 0.2252"and the absolute average negative peak to tracking error reduces from 0.8881"to 0.3984".Moreover,the azimuth axis tracking MSE reduces from 0.1155"to 0.0737",which decreases by 36.2%.Experimental results validate the high precision,facile portability and high real-time ability of our approach.

关键词： telescopes instrumentation:detectors methods:analytical

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Waste to wealth: Oxygen-nitrogen-sulfur codoped lignin-derived carbon microspheres from hazardous black liquors for high-performance DSSCs

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Journal of Energy Chemistry 2023年第8期83卷 549-563,I0013页

作者： Wenjie Cheng Caichao Wan Xingong Li Huayun Chai Zhenxu Yang Song Wei Jiahui su Xueer Tang Yiqiang Wu College of Materials Science and Engineering Central South University of Forestry and TechnologyChangsha 410004HunanChina School of Biomedical Engineering The University of SydneySydneyNew South Wales 2006Australia The University of Sydney Nano Institute The University of SydneySydneyNew South Wales 2006Australia

Carbon materials are effective substitutes for Pt counter electrodes(CEs) in dye-sensitized solar cells(DSSCs). However, many of these materials, such as carbon nanotubes and graphene, are expensive and require complex preparation process. Herein, waste lignin, recycled from hazardous black liquors,is used to create oxygen-nitrogen-sulfur codoped carbon microspheres for use in DSSC CEs through the facile process of low-temperature preoxidation and high-temperature self-activation. The large number of ester bonds formed by preoxidation increase the degree of cross-linking of the lignin chains, leading to the formation of highly disordered carbon with ample defect sites during pyrolysis. The presence of organic O/N/S components in the waste lignin results in high O/N/S doping of the pyrolysed carbon,which increases the electrolyte ion adsorption and accelerates the electron transfer at the CE/electrolyte interface, as confirmed by density functional theory(DFT) calculations. The presence of inorganic impurities enables the construction of a hierarchical micropore-rich carbon structure through the etching effect during self-activation, which can provide abundant catalytically active sites for the reversible adsorption/desorption of electrolyte ions. Under these synergistic effects, the DSSCs that use this novel carbon CE achieve a quite high power-conversion efficiency of 9.22%. To the best of our knowledge, the value is a new record reported so far for biomass-carbon-based DSSCs.

关键词： Lignin Carbon microspheres Codoping Hierarchical pores DSSCs

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Effect of Heat Treatment on Reversed Austenite in Cr15 super Martensitic Stainless Steel

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Journal of Iron and Steel Research International 2013年第5期20卷 61-65页

作者： JIANG Wen ZHAO Kun-yu YE Dong LI Jun LI Zhi-dong su Jie Department of Materials Science and Engineering Kunming University of Science and Technology Institute for Structural Materials Central Iron and Steel Research Institute

The effect of different heat treatments on the reversed austenite in Cr15 super martensitic stainless steel was investigated. The experimental results indicate that the microstructure of the steel is composed of tempered martensite and diffused reversed austenite after quenching at 1 050 ℃ and tempering from 550 to 750 ℃. The volume fraction and size of reversed austenite increase with increasing tempering temperature and both of them reach the maximum value at 700 ℃. The volume fraction and size of reversed austenite decrease when the temperature is above 700 ℃. The transmission electron microscope （TEM） results indicate that the orientation relationship between tempered martensite and reversed austenite belongs to Kurdjmov-Sach （K-S） relationship.

关键词： reversed austenite martensite heat treatment Cr15 super martensitic stainless steel

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Synthesis and Crystal Structure of 1,4-Bis-(benztriazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene

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Chinese Journal of Structural Chemistry 2005年第3期24卷 279-282页

作者： CAI Yue-Peng HE Guang-Ping CAI Yi ZHANG Chi su Cheng-Yong KANG Bei-Sheng Dearment of Chemistr South China Normal UniversiyGuanzhou 510631China School of Chemisiry and Chemical Engineering Sun Yer-sen UniversitGuangzhou 510275China School of Pharmacaceutical Sciences Anhui Collegeof Traditional Chinese MedicineHefei 230038China

The title compound 1,4-bis(benztriazol-1-ylmethyl)-2,4,5,6-trimethylbenzene crys- tallizes in the monoclinic system, space group Pbca with a = 9.842(5), b = 9.455(5), c = 22.165(12) ?, V = 2062.6(18) ?3, Dc = 1.277 g/cm3, Z = 4, C24H24N6, Mr = 396.49, μ(MoKa) = 0.079 mm-1 and F(000) = 840. The structure was refined to R = 0.0662 and wR = 0.1891 for 1163 observed reflections (I > 2σ(I)). The title molecule has trans-conformation about the central phenyl ring. The zigzag-like molecules are connected by face-to-face π…π stacking to form an infinite 2D layer.

关键词： bis(benztriazol-1-ylmethyl)-2 4 5 6-trimethylbenzene synthesis crystal structure face-to-faceπ…πinteraction 2D layer

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