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First Biological Records of Palaeoecology Changes Inferred from Pollen since 4800 cal. a B.P. in Alahake Saline Lake of North Xinjiang

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1249-1250页

作者： LI Yumei ZHANG Yun zhao long KONG zhaochen College of Earth Sciences Jilin University Changchun 130061 Jilin China State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy ofSciences Beijing 100093 China Beijing Institute of Geo-Environment Monitoring Beijing 100195 China

Objective As the resource treasury of desert biodiversity,the wetland of Betula halophila has fragile ecologic system and low stability,which causes the sudden reduction of wetland *** Alahake Saline Lake is known for an endangered species,Betula ***,palaeoecology changes of the Alahake Saline Lake have been little ***,it is necessary to

关键词： First Biological Records Alahake Saline Lake

New Evidence of “Little Ice Age” Inferred from ^(14)C and Pollen in the Kanas Wetland, Northern Xinjiang

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 246-247页

作者： LI Yumei ZHANG Yun zhao long KONG zhaochen College of Earth Sciences Jilin University State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing Institute of Geo-Environment Monitoring

“Little Ice Age”(LIA)was first introduced by Matthes in 1939 with reference to the phenomenon of cirque glacier regrowth during the *** is located in the Asian monsoon region,and monsoon circulations on ecological environment have a variety of effects on ecological environment during the ***,existing research has little documented on environmental changes based on pollen during the LIA.A 100-cm-deep section of drilling was collected at the Kanas wetland,northern *** using the data of pollen and^14C,we obtained vegetation types from the study area,which will providenew evidence of“Little Ice Age”in the Altay area.

关键词： Ice effects ^14C was has

Synthesis and characterization of nanocrystalline NaTaO_3

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Rare Metals 2006年第Z2期25卷 69-72页

作者： CHEN Jingfang HU long zhao Jianling TANG Chengchun LI Yangxian School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China School of Material Science and Engineering Hebei University of Technology Tianjin 300130 China

Tantalum pentoxide reacts actively with concentrated NaOH solution under hydrothermal conditions at 180 ℃. In the reaction between NaOH solution and Ta2O5, the structure and composition of the tantalates depend on the reaction time, and the structure evolution results in a remarkable change in light absorption. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet-visible (UV-Vis) diffused reflection spectrum were used to characterize various properties of the obtained solid products. At 180 ℃, the reaction proceeds rapidly. With the increase of time, the reflection peaks of unreacted Ta2O5 in the XRD patterns becomes weaker and weaker. Pure NaTaO3 is obtained after 60 min, which is well crystallized with a uniform cubic morphology.

关键词： NaTaO3 hydrothermal characterization crystal morphology

Visible Light-Induced[3+2]Annulation Reaction of Alkenes with Vinyl Azides:Direct Synthesis of Functionalized Pyrroles

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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： Ming Yang Xin-Yu Wang Jie Wang Yu-long zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye *** substrate scope and high functional group tolerance were demonstrated by more than 50 *** reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions

Colonization process of Arabidopsis thaliana roots by a green fluorescent protein-tagged isolate of Verticillium dahliae

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Protein & Cell 2014年第2期5卷 94-98页

作者： Pan zhao Yun-long zhao Yun Jin Tao Zhang Hui-Shan Guo State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(Beijing) Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Dear Editor, Verticillium wilt, caused by the soil-borne fungus Verticillium dahlia Klep., poses a major threat to a broad host range of more than 400 plant species, including economically impor- tant cotton, and causes serious loss of lint yield in China, the USA and may other countries （Bell, 1992; Bejorano-Alcazar et al., 1995; Zhang et al., 2012）. The colonization of cotton roots by V. dahliae in soil naturally leads to the colonization of vascular tissues in cotton （Garber and Houston, 1966; Gerik and Huisman, 1988）. Recently, the development of confocal laser scanning microscopy （CLSM） has significantly increased our knowledge of the colonization process of V. dahliae on various plant roots （Eynck et al., 2007; Vallad and Subbarao, 2008; Prieto et al., 2009; Zhang et al., 2012）. However, the comprehensive observation of the cotton living root colonization process by V. dahliae under CLSM is not likely to be practicable due to the large size of cotton roots.

关键词： Colonization process Arabidopsis thaliana roots green fluorescent

Structure identification of 4-amino-2-(arylamino)thiazole-5-carboxylic esters

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Chinese Chemical Letters 2016年第2期27卷 302-304页

作者： Hai-long zhao Hua-long Chen Jie Zhou Bai-Ling Xu Beijing Key Laboratory of Active Substance Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College

In our previous work,we found a new method by chance for the synthesis of thiazole derivatives with diversified substitutes on 2-and 5-positions of the thiazole scaffold which was published in Chinese Chemical Letters[2014,Vol.25 p.411].The structures were identified by ~1H NMR,^（13）C NMR and HRMS as 2-alkoxy-4-amino-Narylthiazole-5-carboxamides.

关键词： In ppm Structure identification of 4-amino-2 arylamino)thiazole-5-carboxylic esters HRMS

^(18)F-FDG PET/CT for malignant small intestinal neoplasms

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Nuclear Science and Techniques 2010年第2期21卷 94-98页

作者： SUN long zhao long LUO Zuoming WEI Jihong SUN Yonghong YANG Rongshui WU Hua Minnan PET Center and Department of Nuclear Medicine No1 Hospital Affiliated to Xiamen Universit） Xiamen 316003. China

In this paper, 18F-FDG PET/CT data of 19 malignant SINs (small intestinal neoplasms) were consecutively reviewed. Nnine patients accepted PET/CT scan for preoperative diagnosis and staging, while ten patients presented follow-up after treatment and restaging. The results were correlated with abdomen enhanced CT and surgical pathological findings. Abdominal pain and weight loss were the most common findings. About 16% SINs located in the duodenum, 52% in the jejunum and 32% in the ileum. Lymphoma was the most frequent neoplasms. PET/CT revealed residual or recurrent malignant SINs in 5 patients who had negative or non-definite findings by abdomen CT and demonstrated extra-abdomen metastasis in 3 patients. Clinical decisions of treatment were changed for 6 patients after PET/CT examinations. The 18F-FDG PET/CT were better than CT in accuracy, negative predictive value and positive predictive value (89.5% vs 68.4%, 100% vs 66.7%, and 81.8% vs 69.2%, respectively). Whole body 18F-FDG PET/CT may be an effective molecular imaging method for staging and restaging of malignant SINs.

关键词： CT检查 PET FDG 肠肿瘤恶性增强扫描后续处理十二指肠

Crystal Structure of Diethyl[2,3-Di(Ethoxycarbonyl)-2,3-di(p-nitrophenyl)]Succinate

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Chinese Chemical Letters 2001年第12期12卷 1131-1134页

作者： Zheng Hua WANG zhao long LI Xiao Yin HONG Department of Chemistry TsinghuaUniversityBeijing 100084

A new conformational carbon-carbon bond free radical initiator diethyl [2,3-di(ethoxycarbonyl)-2,3-di(p-nitrophenyl)] succinate (EMNPS) was synthesized and identified by elemental analysis, FAB-MS, IR and H-1 NMR spectroscopy. The analytical results of single crystal X-ray show the conformation of EMNPS tends to be a stagger gauche form, and torsion angle of the two gauche phenyls is smaller than 60 degrees. There is obvious elongation in central carbon-carbon bond length (0.161 nm). EMNPS can be decomposed into two relatively stable free radicals measured by ESR. By initiating bulk polymeriza-tion of methyl methacrylate (MMA), EMNPS shows the ability of controlling the molecular weight of polymers.

关键词： "Living" free radical polymerization Crystal structure Diethyl [2,3-di(ethoxycarbonyl)-2,3-di(p-nitrophenyl)] succinate Synthesis

Redox Polymerization of Methyl Methacrylate in the Fluorous Triphasic System

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Chinese Chemical Letters 2006年第2期17卷 258-260页

作者： Shi Zhen CHEN Yun Peng BAI zhao long LI Department of Chemistry Tsinghua University Beijing 100084

Methyl methacrylate （MMA） was polymerized by using of benzoyl peroxide （BPO） and N, N-dimethylaniline （DMA） as an redox initiator in fluorous triphasic system at room temperature. The polymerization was occurred in both initiator layer and monomer layer in a U-tube. It was found that PMMA obtained from the initiator layer with relatively narrow polydispersity.（PDI = 1.38）

关键词： Fluorous triphasic system redox polymerization methyl methacrylate.