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A Novel Total Synthesis of (±)Shikonin

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Chinese Chemical Letters 2006年第7期17卷 871-873页

作者： De Feng XU xiao juan GUO zhao Hui XU Shao Shun LI School of Pharmacy Shanghai Jiaotong University Shanghai 200030

A novel total synthesis of （±）shikonin 1 was presented. The key intermediate 6 was achieved by the formylation of 1,8：4,5-bis（methylenedioxy）naphthalene 5 with N-methylformanilide in good yield. It was first reported that the addition of prenyllithium to 2-formyl-1,8：4,5- bismethylenedioxy naphthalene 6 gave 2-（1-hydroxy-4-methylpentyl） 1,8：4,5-bis（methylenedioxy） naphthalene 8 in 45% yield and 2-（1-hydroxy-2,2-dimethyl-3-butenyl）-1,8：4,5-bis（methylenedioxy）naphthalene 9 in 48% yield. After the electrooxide deprotection of 8, （±）shikonin 1 was prepared in high yield.

关键词： (±)Shikonin total synthesis prenyllithium.

Synthesis and Crystal Structure of 4,4′-Diamino-N,N′-diethyl Bisbenzenesulfamide

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Chinese Journal of Structural Chemistry 2007年第2期26卷 177-183页

作者： WANG Li-Min PAN xiao-juan FAN zhao-Yu YANG Liu-Bo LIU Lian TIAN He Laboratory for Advanced Materials Institute of Fine ChemicalsEast China University of Science and Technology Shanghai 200237 China

A new compound of 4,4＇-diamino-N,V＇-diethyl bisbenzenesulfamide （C18H26N4O4S2, Fw = 426.55） has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to the monoclinic system, space group P21/c with a = 10.0623（9）, b = 13.6759（13）, c =15.5309（14） A, β = 100.482（2）°, V= 2101.6（3） A^3, Dc = 1.348 g/cm^3, F（000） = 904, μ = 0.285 mm^-1, Z = 4, the final R = 0.0512 and wR = 0.1363 for 3485 observed reflections with I 〉 2σ（I）. The structure of the title compound is pseudo secondary axisymmetric, and the two sulfamide-groups show distorted tetrahedral configurations.

关键词： 4,4'-diamino-N,V'-diethyl bisbenzenesulfamide synthesis crystal structure

HETEROAROMATIC POLYMERS—HIGH TEMPERATURE POLYPYRROLONES DERIVED FROM 2,6-BIS(3',4'-DIAMINOPHENYL)-4-BIPHENYLPYRIDINE AND VARIOUS AROMATIC DIANHYDRIDES

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Chinese Journal of Polymer Science 2005年第5期23卷 521-529页

作者： Hai-xia Yang Jin-gang Liu xiao-juan zhao Yan-feng Li Lin Fan Shi-yong Yang School of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 China Laboratory of Advanced Polymer Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

A new type of aromatic tetraarnine containing biphenyl moiety in the side chain was synthesized via a modified Chichibabin＇s reaction. 3-Nitro-4-acetamidoacetophenone was reacted with 4-phenyl benzaldehyde in the presence of ammonium acetate to obtain 2,6-bis（3＇,4＇-diaminophenyl）-4-biphenyl pyridine （DPPA）. A series of polypyrrolones （PPys） were prepared using tetraamine and various aromatic dianhydrides via a two-step cyclization procedure. All the PPys show excellent high temperature stabilities with the initial decomposition temperatures of 530-549℃ and residual weight ratio of 49%-80% at 750℃ in nitrogen. The polymers exhibit no apparent glass transition temperatures （Tgs） except PPy-1 （Tg= 327℃）, which is derived from tetraamine DPPA and 2,2-bis[4-（3＇,4＇-dicarboxyphenoxy）-phenyl]propane dianhydride （BPADA）. In addition, the polymers have acceptable mechanical properties with the tensile strength of 65-94 MPa. The PPy films show excellent hydrolysis-resistance in alkaline aqueous medium and could maintain most of the properties even after boiling in 10% aqueous sodium hydroxide solution for a week.

关键词： Tetraamine Polypyrrolone Pyridine High temperature polymers Film Hydrolysis-resistance.

Absolute measurement of radiant power for synchrotron radiation monochromatized X-rays

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Radiation Detection Technology and Methods 2020年第1期4卷 97-105页

作者： Fan Li Yi-Dong zhao Pei-Wei Wang Lei Zheng Si-Ming Guo Ji Wang Kun Tang xiao-juan zhao Jian-Min Li Institute of High Energy Physics Chinese Academy of SciencesBeijingChina National Institute of Metrology BeijingChina University of Chinese Academy of Sciences BeijingChina

Purpose Absolute measurement of radiant power in the X-ray region is essential for many applications in astrophysics,spectroscopy,and X-ray *** paper presents a dependable method of absolute measurement of radiant power for synchrotron radiation monochromatized *** A free-air ionization chamber was examined closely and employed as the detector in the present *** measuring principle was discussed,and the correction factors were *** measurement of radiant power for synchro-tron radiation monochromatized X-rays in the region of 6-20 keV was performed using the free-air ionization chamber at Beijing Synchrotron Radiation *** a verification and an important application,photodiodes were calibrated against the free-air ionization *** Relative standard uncertainties of absolute measurement using free-air ionization chamber are about 1%.Calibration of photodiodes within the photon energy range from 6 to 20 keV has relative standard uncertainties below 1.5%.Conclusion The free-air ionization chamber is qualified to be used in many disciplines to support the measurement of opti-cal radiation.

关键词： Absolute measurement Radiant power Free-air ionization chamber Synchrotron radiation X-ray

OsEIL1 and OsEIL2,two master regulators of rice ethylene signaling,promote the expression of ROS scavenging genes to facilitate coleoptile elongation and seedling emergence from soil

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Plant Communications 2024年第3期5卷 93-105页

作者： Jinzhu Qiao Ruidang Quan juan Wang Yuxiang Li Dinglin xiao Zihan zhao Rongfeng Huang Hua Qin Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China National Key Facility of Crop Gene Resources and Genetic Improvement Beijing 100081China

Successful emergence from the soil is a prerequisite for survival of germinating seeds in their natural *** rice,coleoptile elongation facilitates seedling emergence and establishment,and ethylene plays an important role in this ***,the underlying regulatory mechanism remains largely ***,we report that ethylene promotes cell elongation and inhibits cell expansion in rice coleoptiles,result-ing in longer and thinner coleoptiles that facilitate seedlings emergence from the *** analysis showed that genes related to reactive oxygen species(ROS)generation are upregulated and genes involved in ROS scavenging are downregulated in the coleoptiles of ethylene-signaling *** investiga-tions showed that soil coverage promotes accumulation of ETHYLENE INSENSITIVE 3-LIKE 1(OsEIL1)and OsEIL2 in the upper region of the coleoptile,and both OsEIL1 and OsEIL2 can bind directly to the promoters of the GDP-mannose pyrophosphorylase(VTC1)gene OsVTC1-3 and the peroxidase(PRX)genes OsPRX37,OsPRX81,OsPRX82,and OsPRX88 to activate their *** leads to increased ascorbic acid content,greater peroxidase activity,and decreased ROS accumulation in the upper region of the *** of ROS accumulation promotes coleoptile growth and seedling emergence from *** deepen our understanding of the roles of ethylene and ROS in controlling coleoptile growth,and this information can be used by breeders to produce rice varieties suitable for direct seeding.

关键词： ethylene ROS coleoptile growth emergence rate rice

Attractor for the Extensible Beam Equation with Nonlocal Weak Damping on Time–Dependent Space

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1115-1126页

作者： Chun Xiang zhao Feng juan MENG Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013P.R.China School of Mathematics and Physics Jiangsu University of TechnologyChangzhou 213001P.R.China

In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at *** the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condition(C_(t))method and more detailed *** results obtained essentially improve and complete some previous works.

关键词： Time-dependent attractor extensible beams equation nonlocal weak damping

A novel Ce_(0.485)Zr_(0.485)Y_(0.03)O_(2) composite oxide with surface doping of Y and its application in Pd-only three-way catalyst

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Rare Metals 2024年第2期43卷 749-757页

作者： Zheng zhao Wei-Xin zhao Yong-Qi Zhang Mei-Sheng Cui Yong-Ke Hou Dong-Ming Chen juan-Yu Yang Zong-Yu Feng xiao-Wei Huang National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.GRINM Group Corporation LimitedBeijing100088China Griem Hi-Tech Co.Ltd. Langfang065000China Rare Earth Functional Materials(Xiong’an)Innovation Venter Co.Ltd. Baoding071700China

The ceria-zirconia compound oxide-supported noble metal Pd(Pd@CZ)is widely used in three-way ***,the surface structure of CZ plays an important role in catalytic activity of ***,how to regulate the surface structure of CZ and clarify the structure–activity relationship is still a *** this paper,a strategy is proposed to develop high activity Pd@CZ nanocatalysts by tuning Y doping sites in *** precipitate-deposition method is developed to prepare the novel Ce_(0.485)Zr_(0.485)Y_(0.03)O_(2) composite with surface doping of Y(CZ-Y-S).In addition,the Pd@CZ-Y-S(Pd supported on CZ-Y-S)exhibits superior catalytic activity for HC,CO,and NO oxide,wherein,for CO and C_(3)H_(6) oxidation,the low-temperature activity of Pd@CZ-Y-S is still 20%higher than that of Pd@CZ-Y-B(Y bulk doping)and commercial Pd@CZ after 1000℃/4 h *** effect mechanism is further studied by density functional theory(DFT)*** with Pd@CZ-Y-B,Pd@CZ-Y-S shows the lower CO oxide reaction energy barriers due to the weaker adsorption strength of *** Y surface doping strategy could provide valuable insights for the development of highly efficient Pd@CZ catalyst with extensive applications.

关键词： Rare earth Ceria-zirconia-supported Pd Surface doping Experiment and theory Catalytic application

Enhanced electrical performance in CaBi_(4)Ti_(4)O_(15)ceramics through synergistic chemical doping and texture engineering

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Journal of Materiomics 2024年第2期10卷 471-479页

作者： Le zhao Guohao Li xiao Zhai Weijie Kuai Yuzhi Zhai Gang Tian Zhigang Gai Minglei zhao juan Du Hongjun Zhang Limei Zheng School of Information and Automation Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan250100China Center for Optics Research and Engineering(CORE) Key Laboratory of Laser and Infrared System of Ministry of EducationShandong UniversityQingdaoShandong266237China College of Materials Science and Engineering Liaocheng UniversityLiaocheng252059China Functional Materials and Acoustooptic Instruments Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080China

High-temperature piezoelectric materials with excellent piezoelectricity,low dielectric loss and large resistivity are highly desired for many industrial sectors such as aerospace,aircraft and nuclear *** a synergistic design strategy combining microstructural texture and chemical doping is employed to optimize CaBi 4Ti 4O15(CBT)ceramics with bismuth layer *** textured microstructure with an orientation factor of 80%e82%has been successfully achieved by the spark plasma sintering ***,by doping MnO_(2),both advantages of hard doping and sintering aids are used to obtain the excellent electrical performance of d_(33)=27.3 pC/N,tandδ-0.1%,Q_(31)~2,307 and electrical re-sistivityρ~6.5×10^(10)Ω·*** to 600℃,the 0.2%(in mass)Mn doped CBT ceramics still exhibit high performance of d_(33)=26.4 pC/N,r~1.5×10^(6)Ω·cm and tandδ~15.8%,keeping at an applicable level,thus the upper-temperature limit for practical application of the CBT ceramics is greatly *** work paves a new way for developing and fabricating excellent high-temperature piezoelectric materials.

关键词： CaBi_(4)Ti_(4)O_(15) Piezoelectricity Mechanical quality factor Resistivity

Current understanding of ELF4 deficiency:a novel inborn error of immunity

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World Journal of Pediatrics 2024年第5期20卷 444-450页

作者： Hong-Qiang Du xiao-Dong zhao Department of Rheumatology&Immunology National Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChongqing Key Laboratory of Child Rare Diseases in Infection and ImmunityChildren’s Hospital of Chongqing Medical UniversityZhongshan Er Road 136Yuzhong DistrictChongqingChina

Background ELF4 deficiency has been recently recognized as a novel disorder within the spectrum of inborn errors of immunity(IEIs),specifically categorized as a“disease of immune dysregulation.”Cases of this condition,reported by our team and others,are very limited *** such,our current knowledge of this new disease remains *** review aims to provide a brief overview of the clinical manifestations,pathogenesis,and treatment strategies for this novel *** sources A comprehensive review was conducted after an extensive literature search in the PubMed/Medline database and websites concerning transcriptional factor ELF4 and reports concerning patients with ELF4 *** search strategy was“ELF4 OR ETS-related transcription factor Elf-4 OR EL4-like factor 4 OR myeloid Elf-1-like factor”as of the time of manuscript *** The current signature manifestations of ELF4 deficiency disorder are recurrent and prolonged oral ulcer,abdominal pain,and diarrhea in pediatric *** some cases,immunodeficiency and autoimmunity can also be *** Sanger sequencing or whole exome sequencing can be used to detect variation in ELF4 *** blotting for ELF4 expression of the patient’s cells can confirm the pathogenic effect of the *** fully confirm the pathogenicity of the variant,further functional test is strongly *** and biologics are the mainstream management of ELF4 deficiency *** Pediatric males presenting with recurring ulcerations in digestive tract epithelium with or without recurrent fever should be suspected of *** atypical presentations are prominent,variations in ELF4 gene should be carefully evaluated functionally due to the complex nature of ELF4 *** of treating DEX includes use of glucocorticoid and biologics and more precise treatment needs more patients to identify and further mechanistic study.

关键词： ELF4 transcription factor Immune dysregulation Inborn errors of immunity Mechanism Recurrent infections