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Rice science 2007年第4期14卷 289-294页

作者： HAO Hu-lin WEI You-zhang YANG xiao-e feng Ying wu Chun-yong Key Laboratory of Environment Remediation and Ecosystem Health Ministry of Education College of Natural Resource and Environment Science Zhejiang University Hangzhou 310029 China

In a pot experiment, effects of N fertilizer application on the concentrations of Fe, Mn, Cu and Zn in shoot of rice and the quality of brown rice were studied. In the treatments with N fertilizer application, the concentrations of Fe, Mn, Cu and Zn in most parts of rice shoot increased compared with control （no N fertilizer application）. This indicated that the transportation ability of microelements from root to shoot in rice was improved with N fertilizer application. Effect of N fertilizer on IR68144 was similar to that of on IR64, but the concentrations of the microelements in plant differed, suggesting that the characteristic expression of the two rice genotypes was not controlled by the amount of N fertilizer supplied. The concentrations of those microelements in brown rice increased at first and then decreased with increasing N fertilizer application, reaching the highest at 160 kg/ha, at which the Fe, Mn, Cu and Zn concentrations in brown rice increased by 28.96%, 41.34%, 58.31% and 16.0% for IR64, and by 22.16%, 13.75%, 8.75% and 20.21% for IR68144 compared with control, respectively. Moreover, N fertilizer promoted the accumulation of protein, decreased the accumulation of amylose in grain, and enhanced gel consistency of brown rice. These results indicate that appropriate N fertilizer management could increase micronutrient contents in grain and improve nutrition quality of rice.

关键词： rice nitrogen fertilizer microelement quality trait nutrient concentration protein content amylose content

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming wu Lin He Lin-Sen Ye xiao-feng Yang Jia-Jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

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通过亲和性调控实现可控自由基羰基化反应

有机化学 2022年第9期42卷 3007-3009页

作者：张有灿吴小锋中国科学院大连化学物理研究所清洁能源国家实验室大连116023 莱布尼茨催化研究所德国罗斯托克18059

基于一氧化碳(CO)作为廉价且丰富的C1源的羰基化反应已成为合成羰基化合物的最有效方法之一,在工业和学术界备受关注,并取得了令人瞩目的进展[1].其中过渡金属催化烯烃的羰基化反应是一个重要的策略用于合成包括β-内酰胺[2]、醛[3]、... 详细信息

基于一氧化碳(CO)作为廉价且丰富的C1源的羰基化反应已成为合成羰基化合物的最有效方法之一,在工业和学术界备受关注,并取得了令人瞩目的进展[1].其中过渡金属催化烯烃的羰基化反应是一个重要的策略用于合成包括β-内酰胺[2]、醛[3]、烷基羧酸及其衍生物[4-5]等羰基化合物;另外,过渡金属催化芳基卤化物环化羰基化也能用于合成含氮杂环酰胺[6]和含氮杂环酮[7].

关键词：含氮杂环羰基化反应羧酸及其衍生物过渡金属催化羰基化合物亲和性自由基环化

The Hilbert expansion of the Boltzmann equation in the incompressible Euler level in a channel

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Science China Mathematics 2025年第1期68卷 39-88页

作者： Feimin Huang Weiqiang Wang Yong Wang feng xiao Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and StatisticsHunan Normal University

The study of the hydrodynamic limit of the Boltzmann equation with physical boundary is a challenging problem due to the appearance of the viscous and Knudsen boundary *** this paper,the hydrodynamic limit from the Boltzmann equation with the specular reflection boundary condition to the incompressible Euler equations in a channel is *** on the multi-scaled Hilbert expansion,the equations with boundary conditions and compatibility conditions for interior solutions,and viscous and Knudsen boundary layers are derived under different scaling,***,some uniform estimates for the interior solutions,and viscous and Knudsen boundary layers are *** the help of the L2-L∞framework and the uniform estimates obtained above,the solutions to the Boltzmann equation are constructed by the truncated Hilbert expansion with multiscales,and hence the hydrodynamic limit in the incompressible Euler level is justified.

关键词： Boltzmann equation incompressible Euler equations hydrodynamic limit Hilbert expansion specular reflection boundary condition viscous boundary layer Knudsen boundary layer

AMSOSININE,A NEW INDOLE ALKALOID FROM AMSONIA SINENSIS

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Chinese Chemical Letters 1991年第4期2卷 297-298页

作者： Hong Mei LIU xiao Zhang feng Bin wu Qi Tai ZHENG Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing 100050

Amsosinine,a new indole alkaloid was isolated from Amsonia *** structure and relative configuration have been determined by detailed spectral *** X-ray crystal structure analysis fur- ther confirms our assignments.

关键词： Am AMSOSININE,A NEW INDOLE ALKALOID FROM AMSONIA SINENSIS

Interferon-gamma and tumor necrosis factor-alpha synergistically enhance the immunosuppressive capacity of human umbilical-cordderived mesenchymal stem cells by increasing PD-L1 expression

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World Journal of Stem Cells 2023年第8期15卷 787-806页

作者： Zhuo Chen Meng-Wei Yao Zhi-Lin Shen Shi-Dan Li Wei Xing Wei Guo Zhan Li xiao-feng wu Luo-Quan Ao Wen-Yong Lu Qi-Zhou Lian Xiang Xu Xiang Ao Department of Stem Cell&Regenerative Medicine State Key Laboratory of TraumaBurn and Combined InjuryDaping HospitalArmy Medical UniversityChongqing 400042China College of Basic Medical Sciences Army Medical UniversityChongqing 400038China Department of Orthopedics Daping HospitalArmy Medical UniversityChongqing 400042China Department of Hepatobiliary Surgery The First Affiliated Hospital of Wenzhou Medical UniversityThe South of Shangcai VillageWenzhou 325005Zhejiang ProvinceChina Department of Medicine Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong 999077China Department of Orthopedics 953 Hospital of PLA ArmyShigatse Branch of Xinqiao HospitalArmy Medical UniversityShigatse 857000Tibet Autonomous RegionChina

BACKGROUND The immunosuppressive capacity of mesenchymal stem cells(MSCs)is dependent on the“license”of several proinflammatory factors to express immunosuppressive factors such as programmed cell death 1 ligand 1(PD-L1),which determines the clinical therapeutic efficacy of MSCs for inflammatory or immune *** MSCs,interferon-gamma(IFN-γ)is a key inducer of PD-L1 expression,which is synergistically enhanced by tumor necrosis factor-alpha(TNF-α);however,the underlying mechanism is *** To reveal the mechanism of pretreated MSCs express high PD-L1 and explore the application of pretreated MSCs in ulcerative *** We assessed PD-L1 expression in human umbilical-cord-derived MSCs(hUC-MSCs)induced by IFN-γand TNF-α,alone or in ***,we performed signal pathway inhibitor experiments as well as RNA interference experiments to elucidate the molecular mechanism by which IFN-γalone or in combination with TNF-αinduces PD-L1 ***,we used luciferase reporter gene experiments to verify the binding sites of the transcription factors of each signal transduction pathway to the targeted gene ***,we evaluated the immunosuppressive capacity of hUC-MSCs treated with IFN-γand TNF-αin both an in vitro mixed lymphocyte culture assay,and in vivo in mice with dextran sulfate sodium-induced acute *** Our results suggest that IFN-γinduction alone upregulates PD-L1 expression in hUC-MSCs while TNF-αalone does not,and that the co-induction of IFN-γand TNF-αpromotes higher expression of ***-γinduces hUCMSCs to express PD-L1,in which IFN-γactivates the JAK/STAT1 signaling pathway,up-regulates the expression of the interferon regulatory factor 1(IRF1)transcription factor,promotes the binding of IRF1 and the PD-L1 gene promoter,and finally promotes PD-L1 *** TNF-αalone did not induce PD-L1 expression in hUCMSCs,the addition of TNF-αsignificantly enhanced IFN-γ-induced JAK/STAT1/IRF1 ***-αup

关键词： Human umbilical-cord-derived mesenchymal stem cells Programmed cell death 1 ligand 1 Immunomodulation Interferon-gamma Tumor necrosis factor-alpha Ulcerative colitis

Palladium-catalyzed oxidative double alkoxycarbonylation of ethylene toward succinic acid derivatives

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Green Carbon 2024年第2期2卷 205-208页

作者： Zhi-Peng Bao Cunyao Li Li Yan Yunjie Ding xiao-feng wu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China Leibniz-Institut für Katalyse e.V. Rostock 18059Germany

Employing biodegradable plastics is one of the choices to solve white pollution *** succinate(PBS),as a biodegradable plastic with good stability and heat resistance,is produced by polymerization of succinic acid and butylene ***,inadequate supply of the direct upstream material succinic acid restricts the development of this *** this work,we provide a carbonylative strategy to construct succinic acid derivatives from carbon monoxide(CO),ethylene and *** reaction catalyzed by palladium catalyst under oxidative conditions.

关键词： Ethylene Alcohols Palladium Carbonylation Succinic acid derivatives

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China Chemistry 2025年第1期68卷 257-263页

作者： Jiapian Huang Chenxin Wang Xu Wang xiaoyu Zhou Wei xiao Jie wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

关键词： β-chiral sulfones chiral cyclic sulfinamides sulfur dioxide insertion asymmetric radical cyclization stereoselectivity

Bi对铸造Al-Mg_2Si金属基复合材料组织与干摩擦磨损性能的影响(英文)

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中国有色金属学会会刊：英文版 2013年第6期23卷 1532-1542页

作者：武晓峰张广安伍复发辽宁工业大学材料科学与工程学院锦州121001

研究不同Bi含量的添加对Al-15Mg2Si原位金属基复合材料组织与干磨擦磨损性能的影响。结果表明,Bi的适量添加对复合材料中的初生和共晶Mg2Si相具有明显的变质效果。含Bi复合材料的磨损率和摩擦系数都小于无Bi复合材料的。Bi改变了复合材... 详细信息

研究不同Bi含量的添加对Al-15Mg2Si原位金属基复合材料组织与干磨擦磨损性能的影响。结果表明,Bi的适量添加对复合材料中的初生和共晶Mg2Si相具有明显的变质效果。含Bi复合材料的磨损率和摩擦系数都小于无Bi复合材料的。Bi改变了复合材料的磨损机理,1%Bi的添加使其从磨粒磨损、粘着磨损和疲劳磨损转变为微弱磨粒磨损和粘着磨损,4%Bi的添加有效地抑制了摩擦表面初生Mg2Si颗粒裂纹的产生,避免了粘着磨损和疲劳磨损,使复合材料的磨损成为单一的微弱磨粒磨损。含Bi复合材料耐磨性能的改善是Bi对Mg2Si相的变质作用和Bi颗粒自润滑作用的综合结果。

关键词： Al-Mg2Si复合材料铸造 Bi添加干摩擦性能

单电子还是双电子?反应底物决定的铁催化未活化烷基卤代物与胺、酰胺和吲哚的酰胺化反应机理

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Chinese Journal of Catalysis 2023年第4期47卷 121-128页

作者：艾汉均赵丰乾吴小锋莱布尼茨催化研究所德国罗斯托克中国科学院大连化学物理研究所辽宁大连116023

铁廉价,储量丰富,铁基催化剂具有独特的催化活性,其催化的羰基化反应备受化学家关注.烷基溴类化合物具有较高的解离能,酰胺和吲哚类化合物具有弱亲核性,上述性质使其发生羰基化转化具有一定的挑战性.本文发展了一种铁催化的酰胺化反应,... 详细信息

铁廉价,储量丰富,铁基催化剂具有独特的催化活性,其催化的羰基化反应备受化学家关注.烷基溴类化合物具有较高的解离能,酰胺和吲哚类化合物具有弱亲核性,上述性质使其发生羰基化转化具有一定的挑战性.本文发展了一种铁催化的酰胺化反应,使用羰基铁催化剂前体,在反应体系中原位生成低价态的活性铁催化中心,并对烷基类底物进行活化.随后发生一氧化碳对碳铁键的插入、酰基铁的生成、亲核试剂的进攻等反应,最后生成目标产品.在该催化体系作用下,未活化的烷基卤代物可以与胺、酰胺和吲哚发生反应,得到较高收率的酰胺、酰亚胺和N-酰基吲哚等化合物,并表现出较好的官能团兼容性.实验发现,含有天然产物骨架的原料也能够高效转化.在反应机理方面,本文进行了分子内、分子间自由基捕捉等研究,结合已报道的谱学研究结果,推断出低价态铁催化中心的存在.结合实验数据以及反应机理研究结果认为,该反应的反应历程是由底物决定的:当以烷基碘类化合物为原料时,经历的是单电子转移(自由基)过程;当以烷基溴类化合物时,经历的是双电子转移过程.综上,本文发展了一种铁催化的烷基卤代物的酰胺化反应,为烷基酰胺合成提供一定参考.

关键词：铁催化羰基化偶联烷基卤代物酰胺酰亚胺