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Journal of Electronics(China) 2010年第4期27卷 453-457页

作者： sun yufa du yan shao yong Key Lab. of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China

The Asymptotic Waveform Evaluation (AWE) technique is an extrapolation method that provides a reduced-order model of linear system and has already been successfully used to analyze wideband electromagnetic scattering problems. As the number of unknowns increases, the size of Method Of Moments (MOM) impedance matrix grows very rapidly, so it is a prohibitive task for the computation of wideband Radar Cross Section (RCS) from electrically large object or multi-objects using the traditional AWE technique that needs to solve directly matrix inversion. In this paper, an AWE technique based on the Characteristic Basis Function (CBF) method, which can reduce the matrix size to a manageable size for direct matrix inversion, is proposed to analyze electromagnetic scattering from multi-objects over a given frequency band. Numerical examples are presented to il-lustrate the computational accuracy and efficiency of the proposed method.

关键词： Method of Moments (MOM) Radar Cross Sections (RCS) Characteristic Basis Func-tion (CBF) method Asymptotic Waveform Evaluation (AWE) Multi-objects

Extraction and kinetic analysis of Pb and Sr from the leaching residue of zinc oxide ore

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 201-209页

作者： Xiao-yi Shen Yuan-yong Liang Hong-mei shao Yi sun yan Liu Yu-chun Zhai Key Laboratory for Ecological Utilization of Multimetallic Mineral of Ministry of Education School of MetallurgyNortheastern UniversityShenyang 110819China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang 110159China

NH4HCO3 conversion followed by HCl leaching was performed and proven to be effective in extracting Pb and Sr from zinc extracted *** mechanism and operating conditions of NH4HCO3 conversion,including molar ratio of NH4HCO3 to zinc extracted residual,NH4HCO3 concentration,conversion temperature,conversion time,and stirring velocity,were discussed,and operating conditions were optimized by the orthogonal *** results indicate that NH4HCO3 conversion at temperatures ranging from 25 to 85°C follows the shrinking unreacted core model and is controlled by inner diffusion through the product *** extraction ratios of Pb and Sr under optimized conditions reached 85.15%and 87.08%,***,the apparent activation energies of Pb and Sr were 13.85 and 13.67 kJ·mol^−1,respectively.

关键词： zinc extraction residual NH4HCO3 conversion HCl leaching Pb Sr reaction mechanism kinetics

Improvement in corrosion resistance of Mg_(97)Zn_(1)Y_(2)alloy by Zr addition

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China Foundry 2024年第6期21卷 634-640页

作者： Di-qing Wan Yu-meng sun yan-dan Xue shao-yun Dong Guo-liang Han Yu Wang Fan yang Hao Tang yong-yong Wang School of Materials Science and Engineering East China Jiaotong UniversityNanchang 330013China

Magnesium alloys,known for their exceptional lightweight properties,have presented challenges in various applications due to their limited corrosion *** this study,the corrosion resistance of Mg_(97)Zn_(1)Y_(2)magnesium alloys was enhanced by incorporating Zr elements into the Mg_(97)Zn_(1)Y_(2)matrix,which is distinguished by long periodic stacking ordered(LPSO)*** show that Mg_(97)Zn_(1)Y_(2)-xwt.%Zr(x=0,0.1,0.3,0.6)alloys containing Zr exhibit reduced hydrogen evolution rates and decreased corrosion levels compared with that without Zr,when immersed in a 3.5wt.%NaCl *** of 0.3wt.%Zr results in the most significant improvement,with a corrosion rate as low as 2.261 mL·cm^(-2),representing an 86%reduction from 16.438 mL·cm^(-2)of the base ***,alloys with Zr additions demonstrate a more positive corrosion potential and lower corrosion current density than does the matrix alloy(64.92μA·cm^(-2)).The lowest corrosion current density,21.61μA·cm^(-2),occurs with the addition of 0.3wt.%*** introduction of Zr induces a change in the microstructure of the LPSO phases,increasing the charge transfer resistance within the alloy and thus effectively improving its corrosion resistance.

关键词： magnesium alloys alloying corrosion resistance zirconium

Bioinspired zinc-mediated umpolung thiolation of alkyl electrophiles: reaction development, scope and mechanism

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Science China Chemistry 2024年第3期67卷 898-907页

作者： Yuenian Xu yan Zhang yong Liu Wen-Wu sun Jie Huang Hui He Yingjie Wu Wen Liu shao-Fei Ni Xu-Qiong Xiao Xinxin shao College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China School of Pharmaceutical Sciences South-Central Minzu UniversityWuhan 430074China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guang-dong Province Shantou UniversityShantou 515063China

Zinc-promoted umpolung thiolation of alkyl electrophiles with masked sulfur transfer reagents in the absence of nickel or copper catalysis is described. This protocol proceeds via a SET process of Zn to electrophilic sulfur reagent followed by insertion of Zn into disulfide and nucleophilic thiolation, providing straightforward access to a wide range of alkyl sulfides with broad substrate scope. A neutral TMEDA-ligated four-coordinated zinc thiolate with tetrahedra geometry was synthesized, isolated and fully characterized by NMR, IR and X-ray analysis. More importantly, the chemical reactivity of this active intermediate has been investigated, enabling the construction of C-Se, C-Te, Sb-S and Bi-S bonds to prepare valuable sulfur-containing molecules and beyond.

关键词： umpolung thiolation C(sp^(3))-S bond formation masked sulfur reagents reductive coupling

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Research progress of CO_(2)oxidative dehydrogenation of propane to propylene over Cr-free metal catalysts

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Rare Metals 2022年第7期41卷 2129-2152页

作者： Zhong-Yu Wang Zhen-Hong He Long-Yao Li shao-yan yang Meng-Xin He yong-Chang sun Kuan Wang Jian-Gang Chen Zhao-Tie Liu Shaanxi Key Laboratory of Chemical Additives for Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and TechnologyXi’an 710021China School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi’an 710119China

CO_(2)-assisted oxidative dehydrogenation of propane(CO_(2)-ODHP)is an attractive strategy to offset the demand gap of propylene due to its potentiality of reducing CO_(2)emissions,especially under the demands of peaking CO_(2)emissions and carbon *** introduction of CO_(2)as a soft oxidant into the reaction not only averts the over-oxidation of products,but also maintains the high oxidation state of the redox-active ***,the presence of CO_(2)increases the conversion of propane by coupling the dehydrogenation of propane(DHP)with the reverse water gas reaction(RWGS)and inhibits the coking formation to prolong the lifetime of catalysts via the reverse Boudouard *** effective catalyst should selectively activate the C–H bond but suppress the C–C ***,to prepare such a catalyst remains ***-based catalysts are always applied in industrial application of DHP;however,their toxic properties are harmful to the *** this aspect,exploring environment-friendly and sustainable catalytic systems with Cr-free is an important *** this review,we outline the development of the CO_(2)-ODHP especially in the last ten years,including the structural information,catalytic performances,and mechanisms of chromium-free metal-based catalyst systems,and the role of CO_(2)in the *** also present perspectives for future progress in the CO_(2)-ODHP.

关键词： Propane Dehydrogenation Propylene CO_(2) Chromium-free metals Catalytic performance

Integrative analyses of RNA editing,alternative splicing,and expression of young genes in human brain transcriptome by deep RNA sequencing

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Journal of Molecular Cell Biology 2015年第4期7卷 314-325页

作者： Dong-Dong Wu Ling-Qun Ye yan Li yan-Bo sun Yi shao Chunyan Chen Zhu Zhu Li Zhong Lu Wang David MIrwin yong EZhang Ya-Ping Zhang State Key Laboratory of Genetic Resources and Evolution Yunnan Laboratory of Molecular Biology of Domestic AnimalsKunming Institute of ZoologyChinese Academy of SciencesKunming 650223China Kunming College of Life Science University of Chinese Academy of SciencesKunming 650204China University of Chinese Academy of Sciences BeijingChina Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina Laboratory for Conservation and Utilization of Bio-resource Yunnan UniversityKunming 650091China Department of Laboratory Medicine and Pathobiology University of TorontoTorontoCanada Banting and Best Diabetes Centre University of TorontoTorontoCanada

Next-generation RNA sequencing has been successfully used for identification of transcript assembly,evaluation of gene expression levels,and detection of post-transcriptional *** these large-scale studies,additional comprehensive RNA-seq data from different subregions of the human brain are required to fully evaluate the evolutionary patterns experienced by the human brain ***,we provide a total of 6.5 billion RNA-seq reads fromdifferent subregions of the human brain.A significant correlation was observed between the levels of alternative splicing and RNA editing,which might be explained by a competition between the molecularmachineries responsible for the splicing and editing of *** protein-coding genesdemonstrate biased expression to the neocortical and non-neocortical regions during evolution on the lineage leading to *** found that a significantly greater number of young human protein-coding genes are expressed in the putamen,a tissue that was also observed to have the highest level of RNA-editing *** putamen,which previously received little attention,plays an important role in cognitive ability,and our data suggest a potential contribution of the putamen to human evolution.

关键词： RNA editing human brain transcriptome young gene human brain evolution

Syntheses, Structures and Photoluminescence of Novel Lanthanide-organic Frameworks Based on 1, 4-Bis(3,5-dicarboxylic pyrazol-1-ylmethyl) Benzene

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Chinese Journal of Structural Chemistry 2020年第5期39卷 960-966页

作者： LI Chuang HE yong-Ke shao Na XIONG Gang WU Shuang-yan YOU Li-Xin sun Ya-Guang The Key Laboratory of Inorganic Molecule-based Chemistry of Liaoning Province College of Applied ChemistryShenyang University of Chemical TechnologyShenyang 110142China

Two isomorphic 3D lanthanide metal-organic frameworks,{[Tb(L)0.5(OX)0.5(H2 O)2DMF]·DMF}n(1)and{[Dy(L)0.5(OX)0.5(H2 O)2 DMF]·DMF}n(2),have been prepared under solvothermal conditions based on l,4-bis(3,5-dicarboxylicpyrazol-1-ylmethyl)benzene(H4 L),oxalis acid(H2 OX)and lanthanide *** 1 crystallizes in monoclinic system,space group P21/c with a=9.418(15),b=15.23(2),c=14.47(2)?,β=100.07(3)°,V=2044(5)?3,Z=4,Mr=590.3 g/mol,Dc=1.919 g/cm^3,μ=3.524 mm-1,F(000)=1168,R=0.0893 and wR=0.1902 for 3486 observed reflections(I>2σ(I)).In compound 1,the central terbium(Ⅲ)ions are coordinated with eight atoms,and two neighboring terbium(Ⅲ)ions are linked together by one bridging oxalic acid group to give rise to a[Tb2(OX)(L)4]***[Tb2(OX)(L)4]unit connects to the surrounding six identical ones by the oxygen atoms bridging to lead to a 3D *** 1 exhibits strong luminescent emissions at the solid state owing to the antenna effect of the ligand.

关键词： lanthanide-organic frameworks luminescent emission antenna effect

A 2-bp frameshift deletion at GhDR,which encodes a B-BOX protein that co-segregates with the dwarf-red phenotype in Gossypium hirsutum L.

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Journal of Integrative Agriculture 2023年第7期22卷 2000-2014页

作者： WANG Xue-feng shao Dong-nan LIANG Qian FENG Xiao-kang ZHU Qian-hao yanG yong-lin LIU Feng ZHANG Xin-yu LI yan-jun sun Jie XUE Fei Key Laboratory of Oasis Eco-Agriculture College of AgricultureShihezi UniversityShihezi 832000P.R.China CSIRO Agriculture and Food CanberraACT 2601Australia Cotton Research Institute Shihezi Academy of Agriculture SciencesShihezi 832000P.R.China

Plant architecture and leaf color are important factors influencing cotton fiber *** this study,based on genetic analysis,stem paraffin sectioning,and phytohormone treatments,we showed that the dwarf-red(DR)cotton mutant is a gibberellin-sensitive mutant caused by a mutation in a single dominant locus,designated *** bulked segregant analysis(BSA)and genotyping by target sequencing(GBTS)approaches,we located the causative mutation to a~197-kb genetic interval on chromosome A09 containing 25 annotated *** on gene annotation and expression changes between the mutant and normal plants,GH_A09G2280 was considered to be the best candidate gene responsible for the dwarf and red mutant phenotypes.A 2-nucleotide deletion was found in the coding region of GhDR/GH_A09G2280 in the DR mutant,which caused a frameshift and truncation of *** is a homolog of Arabidopsis AtBBX24,and encodes a B-box zinc finger *** frameshift deletion eliminated the C-terminal nuclear localization domain and the VP domain of GhDR,and altered its subcellular localization.A comparative transcriptome analysis demonstrated downregulation of the key genes involved in gibberellin biosynthesis and the signaling transduction network,as well as upregulation of the genes related to gibberellin degradation and the anthocyanin biosynthetic pathway in the DR *** results of this study revealed the potential molecular basis by which plant architecture and anthocyanin accumulation are regulated in cotton.

关键词： cotton BBX dwarf anthocyanin gibberellin

X-ray-activated long persistent phosphors featuring strong UVC afterglow emissions

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Light(Science & Applications) 2018年第1期7卷 222-232页

作者： yan-Min yang Zhi-yong Li Jun-Ying Zhang Yue Lu shao-Qiang Guo Qing Zhao Xin Wang Zi-Jun yong Hong Li Ju-Ping Ma Yoshihiro Kuroiwa Chikako Moriyoshi Li-Li Hu Li-yan Zhang Li-Rong Zheng Hong-Tao sun College of Physics Science and Technology Hebei University071002 BaodingChina College of Chemistry Chemical Engineering and Materials ScienceSoochow University215123 JiangsuChina Department of Physics Beihang University100191 BeijingChina Department of Physical Science Hiroshima UniversityHigashihiroshimaHiroshima 739-8526Japan Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences201800 ShanghaiChina Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences100049 BeijingChina

Phosphors emitting visible and near-infrared persistent luminescence have been explored extensively owing to their unusual properties and commercial interest in their applications such as glow-in-the-dark paints,optical information storage,and in vivo ***,no persistent phosphor that features emissions in the ultraviolet C range(200–280 nm)has been known to exist so ***,we demonstrate a strategy for creating a new generation of persistent phosphor that exhibits strong ultraviolet C emission with an initial power density over 10 milliwatts per square meter and an afterglow of more than 2 *** characterizations coupled with first-principles calculations have revealed that structural defects associated with oxygen introduction-induced anion vacancies in fluoride elpasolite can function as electron traps,which capture and store a large number of electrons triggered by Xray ***,we show that the ultraviolet C afterglow intensity of the yielded phosphor is sufficiently strong for *** discovery of this ultraviolet C afterglow opens up new avenues for research on persistent phosphors,and it offers new perspectives on their applications in terms of sterilization,disinfection,drug release,cancer treatment,anti-counterfeiting,and beyond.

关键词： ultraviolet fluoride visible

Three minor new compounds from the aerial parts of Leonurus japonicus

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Chinese Chemical Letters 2015年第8期26卷 1000-1003页

作者： Wei-Mao Zhong Zhao-Meng Cui Zhi-Ke Liu yan yang Da-Rong Wu shao-Hua Liu Hui Long Han-Dong sun yong-Jun Dang Wei-Lie Xiao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Molecular Medicine Ministry of Education and Department of Biochemistry and Molecular Biology Fudan University Shanghai Medical College Chengdu No.1 Pharmaceutical Group Co. Ltd.

Phytochemical investigation of the aerial parts of Leonurus japonicus led to the isolation of one new labdane diterpenoid, leojaponin D （1） and two new ionone derivatives, leojaponones A and B （2 and 3）, together with seven known diterpenoids （4-10）. Their structures were elucidated by extensive 1D and 2D NMR spectroscopic data and by comparison with data reported in the literature. Selected isolates were evaluated their effects on lurkat IL2 secretino.

关键词： Leonurus japonicus Diterpenoid lonone derivative Jurkat IL2 secretion