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Coordination-Assembled Lanthanide-Organic Ln3L3 Sandwiches or Ln4L4 Tetrahedron: Structural Transformation and Luminescence Modulation

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Chinese Journal of Chemistry 2019年第7期37卷 657-662页

作者： Shao-jun Hu Xiao-Qing Guo Li-peng Zhou Li-Xuan Cai Qing-fu Sun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences FuzhouFujian 350002 China College of Chemistry Fuzhou University Fuzhou Fujian 350108 ChinaState Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences FuzhouFujian 350002 China University of Chinese Academy of Sciences Beijing 100049 ChinaState Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences FuzhouFujian 350002 China

Photo-functional supramolecular lanthanides assemblies have shown great potential in the materials and biomedical *** new tri(tridentate) ligands (L3 and L4) highlighting small variation of the connection position to the central tridentate linkers have been designed,which leads to the emergent formation of either Ln3L3-type sandwich structures or Ln4L4-type tetrahedral ***,nonlinear enhancement of lanthanide luminescence based on the modulation of inter-ligand charge-transfer states has been revealed on the mix-ligand Ln3L3 *** results provide important guidance for structure-design and photoluminescence optimization of supramolecular lanthanide-organic assemblies.

关键词： Structural Transformation Luminescence Modulation

Exact Solution of a Backward Scattering Kondo Model

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Chinese Physics Letters 1996年第9期13卷 703-706页

作者： WANG Yu-peng PU fu-ke Cryogenic Laboratory Chinese Academy of SciencesBeijing 100080 Department of Physics Guangzhou Teachers’CollegeGuangzhou 510400 Institute of Physics Chinese Academy of SciencesBeijing 100080

To specify the difference between the one-dimensional Kondo problem and the three-dimensional Kondo problem,we consider a model which describes the interaction between one-dimensional free electrons and a magnetic *** ansatz exact results and scaling analysis show that if J_(F)>-|J_(B)|,the Kondo screening *** is no ferromagnetic Kondo screening in such a system but the long range antiferromagnetic Kondo coupling is *** soon as the Coulomb interaction is introduced,the crossovers between the scaling trajectories in the parameter region J_(F)<-|J_(B)|and the trajectories in other parameter regions arise and ferromagnetic Kondo screening may occur.

关键词： Kondo ferromagnetic scaling

Total Synthesis of Nucleoside Antibiotics Amicetin,Plicacetin,and Cytosaminomycin A-D

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Chinese Journal of Chemistry 2021年第10期39卷 2679-2684页

作者： Jiqiang fu peng Xu Biao Yu State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang310024 China

Main observation and conclusion Amicetin and congeners constitute a small family of complex pyrimidine nucleosides,which exhibit strong antibiotic activities against Gram-positive bacteria and notably against strains of Mycobacterium ***,we report chemical synthesis of a series of disaccharide congeners of the amicetin family,including amicetin,plicacetin,and cytosaminomycin A—*** is the first time for successful synthesis of amicetin,the prototypical member,and *** synthetic approach employs glycosyl N-phenyltrifluoroacetimidate and thioglycoside donors to construct the characteristic aminodeoxydisaccharides consisting ofα-(1→4)-glycosidic linkage,uses gold(I)-catalyzed N-glycosylation to furnish 2-deoxy-β-nucleosides,and finally exploits amidation and global deprotection to complete the *** is noteworthy that the 3-O-protecting group in the 2-deoxydisaccharide donors is found to be crucial for a successful N-glycosylation to assemble the cytosaminomycin disaccharide nucleosides.

关键词： Total synthesis Glycosylation Nucleoside Amicetin Cytosaminomycin

A recessive gene controlling male sterility sensitive to short daylength/low temperature in wheat(Triticum aestivum L.)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第11期12卷 943-950页

作者： Xiao-dong CHEN Dong-fa SUN De-fu RONG jun-hua peng Cheng-dao LI College of Plant Science and Technology Huazhong Agricultural University Wuhan 430070 China Shayang Agricultural Research Institute Shayang 448200 China Wuhan Botanical Garden Chinese Academy of Sciences Wuhan 430074 China Department of Agriculture Government of Western Australia South Perth WA 6151 Australia

Utilization of a two-line breeding system via photoperiod-thermo sensitive male sterility has a great potential for hybrid production in wheat （Triticum aestivum L.）. 337S is a novel wheat male sterile line sensitive to both short daylength/Iow temperature and long daylength/high temperature. Five F2 populations derived from the crosses between 337S and five common wheat varieties were developed for genetic analysis. All Fl＇s were highly fertile while segregation occurred in the F2 populations with a ratio of 3 fertile：l sterile under short daylength/Iow temperature. It is shown that male sterility in 337S was controlled by a single recessive gene, temporarily designated as wptms3. Bulked segregant analysis （BSA） coupled with simple sequence repeat （SSR） markers was applied to map the sterile gene using one mapping population. The wptms3 gene was mapped to chromosome arm 1BS and flanked byXgwm413 and Xgwm182 at a genetic distance of 3.2 and 23.5 cM, respectively. The accuracy and efficiency of marker-assisted selection were evaluated and proved essential for identifying homozygous recessive male sterile genotypes of the wptms3 gene in F2 generation.

关键词： Heterosis wptms3 Short daylength/Iow temperature sensitive male sterility Molecular mapping Triticum aestivum

Wetland and habitat dynamics in the evolving landscape of the Middle Yangtze River Basin

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Journal of Geographical Sciences 2025年第1期 88-111页

作者： YANG peng SUN Kaiya ZHU Yanchao XIA jun HUANG Heqing SONG Jingxia SHI Xiaorui LU Xixi Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information Engineering China University of Geosciences Department of Geography National University of Singapore State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

Wetlands play a critical role in the global environment. The Middle Yangtze River Basin(MYRB), known for its abundant wetland resources, has experienced notable changes resulting from the complex interplay of environmental factors. Therefore, we investigated the spatiotemporal characteristics of wetland ecological quality in the MYRB from 2001 to *** the random forest(RF) regression algorithm and patch-generated land-use simulation(PLUS) model, we forecasted variations in wetland habitat quality and their determinants under the Shared Socioeconomic Pathway-Representative Concentration Pathway(SSPRCP) framework from 2035 to 2095. The main findings are as follows:(1) The RF algorithm was optimal for land-use and land-cover(LULC) classification in the MYRB from 2001 to 2020,when notable changes were observed in water bodies and buildings. However, the forested area exhibited an increase and decrease of 3.9% and 1.2% under the SSP1-2.6 and SSP5-8.5 scenarios, respectively, whereas farmland exhibited a diminishing trend.(2) Wetlands were primarily concentrated in the central and eastern MYRB, with counties in the southwest exhibiting superior ecological-environmental quality from 2001 to 2020. Notably,wetland coverage revealed significantly high level, significant changes, frequent but relatively minor changes under the SSP1-2.6, SSP2-4.5, and SSP 5-8.5 scenarios, respectively.(3)Regions with lower habitat quality were primarily concentrated in urbanized areas characterized by frequent human activities, indicating a clear degradation in habitat quality across different scenarios. In conclusion, we established a foundational framework for future investigations into the eco-hydrological processes and ecosystem quality of watersheds.

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A design study on the CSNS LEBT pre-chopper

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 231-235页

作者： LIU HuaChang OUYANG Huafu peng jun HUANG Tao GONG KeYun XU TaoGuang fu ShiNian Institute of High Energy Physics P.O.Box 918Beijing 100049China

The China Spallation Neutron Source (CSNS) front end incorporates a pre-chopper in the Low Energy Beam Transport line (LEBT) that will remove a 530 ns section of beam at approximately 1 MHz rate, which is the RF frequency of the ring at injection. It's one of the most critical devices for properly controlling the injecting beam loss. Physical designing of the pre-chopper is carried out, and the RFQ itself is used as the beam dump of the chopper system. In order to examine the reliability of the pre-chopper design, the beam study of a similar chopper system is successfully performed. The results of physical design and experiments are presented.

关键词： pre-chopper rise/fall time electromagnetic shield

Electrochemical Properties of Tungsten-Alloying-Modified AISI 430 Stainless Steel as Bipolar Plates for PEMFCs used in Marine Environment

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 920-927页

作者： Jin-Long Cui Zhen-Dong Yao Yong-fu Cui fu-peng Cheng Ting Xiao Hong-Liang Sun Ru-Jin Tian jun-Cai Sun Institute of Materials and Technology Dalian Maritime University College of Materials Science and Engineering Dalian Jiaotong University

To improve the corrosion resistance and surface electrical conductivity of AISI 430 stainless steel （430 SS） as bipolar plates for proton exchange membrane fuel cells （PEMFCs） used in marine environment, a tungsten alloying layer has been successfully prepared on 430 SS substrate via the plasma surface diffusion alloying technique. The tungsten- modified （W-modified） 430 SS displays a 7-8 Ixm tungsten alloying layer with a body-centered-cubic structure. The W-modified surface also shows a better hydrophobicity with contact angle of 93.5~ and a lower interfacial contact resistance compared with the untreated 430 SS. The potentiodynamic and potentiostatic polarization and electrochemical impedance spectroscopy measurements show that the corrosion resistance of 430 SS is obviously improved in simulated PEMFC environment （0.05 M H2SO4 ＋ 2 ppm HF ＋ 0.01 M NaC1 solution at 70℃）, after the plasma surface diffusion alloying process.

关键词： Tungsten alloying layer Corrosion resistance Proton exchange membrane fuel cell Interfacial contact resistance Bipolar plates

Accuracy of endoscopic ultrasound-guided needle aspiration specimens for molecular diagnosis of non-small-cell lung carcinoma

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World Journal of Clinical Cases 2020年第21期8卷 5139-5148页

作者： Wei Su Xiang-Dong Tian peng Liu De-jun Zhou fu-Liang Cao Department of Endoscopy Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin’s Clinical Research Center for CancerTianjin 300060China

BACKGROUND Endoscopic ultrasonography-guided fine-needle aspiration(EUS-FNA)and endobronchial ultrasound-guided transbronchial needle aspiration(EBUS-TBNA)are highly sensitive for diagnosing and staging lung *** recent years,targeted therapy has shown great significance in the treatment of non-small cell lung carcinoma(NSCLC).Using these minimally invasive techniques to obtain specimens for molecular testing will provide patients with a more convenient diagnostic *** To evaluate the feasibility and accuracy of tissue samples obtained using EUSFNA and EBUS-TBNA for molecular diagnosis of *** A total of 83 patients with NSCLC underwent molecular testing using tissues obtained from EUS-FNA or EBUS-TBNA at the Tianjin Medical University Cancer Hospital from January 2017 to june *** enrolled patients underwent chest computed tomography or positron emission tomography/computed tomography prior to *** detected abnormal expression of EGFR,KRAS,MET,HER2,ROS1 and anaplastic lymphoma kinase *** patients failed to complete molecular testing due to insufficient tumor *** clinical features,puncture records,molecular testing results and targeted treatment in the remaining 81 patients were *** In a total of 99 tissue samples obtained from 83 patients,molecular testing was successfully completed in 93 samples with a sample adequacy ratio of 93.9%(93/99).Biopsy samples from two patients failed to provide test results due to insufficient tumor *** the remaining 81 patients,62 cases(76.5%)were found to have adenocarcinoma,11 cases(13.6%)had squamous cell carcinoma,3 cases(3.7%)had adenosquamous carcinoma and 5 cases(6.2%)had NSCLC-not otherwise *** results of molecular testing showed EGFR mutations in 21 cases(25.9%),KRAS mutations in 9 cases(11.1%),ROS-1 rearrangement in 1 case(1.2%)and anaplastic lymphoma kinase-positive in 5 cases(6.2%).Twentyfour patients with positive results received targeted ther

关键词： Endobronchial ultrasound-guided transbronchial needle aspiration Endoscopic ultrasonography-guided fine-needle aspiration Non-small cell lung carcinoma Molecular diagnosis Targeted therapy

Influences of Inflow Condition on Non-Axisymmetric Flows in Turbine Exhaust Hoods

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Journal of Thermal Science 2008年第4期17卷 305-313页

作者： Jing-Lun fu Jian-jun LIU Institute of Engineering ThermophysicsChinese Academy of Sciences Beijing 100190 China

The complex 3D flow in a steam turbine exhaust hood model with different inlet swirl and inlet total pressure radial distributions has been simulated by employing CFX-5 and analyzed in this paper. It＇s found that the inlet tangential flow angle at hub has a negative effect on the exhaust hood performance, while a negative gradient of inlet total pressure radial distribution has a positive impact on the hood performances. It＇s also numerically con- firmed that a proper distribution of total pressure at hood inlet can successfully eliminate the negative effects caused by the inappropriate inlet swirl distribution and improve the hood aerodynamic performance.

关键词： turbine exhaust hood inflow conditions non-axisymmetric flow