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Quantifying freeze-melt dynamics of lakes on the Tibetan Plateau using Sentinel-1 synthetic aperture radar imagery

Journal of Mountain Science 2024年第3期21卷 805-819页

作者： JIN Lu CHEN Jun CAI Yu KONG Yecheng WANG Yongfeng DUAN Zheng School of Environment and Energy Engineering Anhui Jianzhu UniversityHefei 230601China Anhui Engineering and Technology Research Center for Smart City Anhui Jianzhu UniversityHefei 230601China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China Department of Physical Geography and Ecosystem Science Lund UniversityLund 22362Sweden

The ice phenology of alpine lakes on the Tibetan Plateau(TP)is a rapid and direct responder to climate changes,and the variations in lake ice exhibit high temporal frequency characteristics.MODIS and passive microwave data are widely used to monitor lake ice changes with high temporal resolution.However,the low spatial resolutions make it difficult to effectively quantify the freeze-melt dynamics of lakes.This work used Sentinel-1 synthetic aperture radar(SAR)data to derive high-resolution ice maps(about 6 days),then with the aid of Sentinel-2 optical images to quantify freeze-melt processes in three typical lakes on the TP(e.g.Selin Co,Ayakekumu Lake,and Nam Co).The results showed that three lakes had an average annual ice period of 125-157 days and a complete ice cover period of 72-115 days,from 2018 to 2022.They exhibit different ice phenology patterns.Nam Co is characterized by repeated episodes of freezing,melting,and refreezing,resulting in a prolonged freeze-up period.Meanwhile,the break-up period of Nam Co lasts for a longer duration(about 19 days),and the break-up exhibits a smooth process.Similarly,Ayakekumu Lake showed more significant inter-annual fluctuations in the freeze-up period,with deviations of up to 28 days observed among different years.Compared to the other two lakes,Selin Co experienced a relatively short freeze-up and break-up period.In short,Sentinel-1 SAR data can effectively monitor the weekly and seasonal variations in lake ice on the TP.Particularly,this data facilitates quantification of the freeze-melt dynamics.

关键词： Lake ice Sentinel-1 SAR Tibetan Plateau Climate change

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Synthesis of Thieno[3,4-b]pyrazine-based Alternating Conjugated Polymers via Direct Arylation for Near-infrared OLED Applications

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Chinese Journal of Polymer Science 2022年第2期40卷 138-146页

作者： Ze-Wang He Qiang Zhang Chen-Xi Li Hong-Ting Han Yan Lu School of Materials Science&Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials&Photoelectric DevicesMinistry of EducationTianjin University of TechnologyTianjin 300384China College of Chemistry Nankai UniversityTianjin 300071China

Three alternating conjugated polymers,namely PFTP,PCz TP,and PSi TP,which combine a thieno[3,4-b]pyrazine(TP)unit with different benzene-based donor units such as 9,9-dioctylfluorene,9-heptadecyl-9H-carbazole and 5,5-dioctyl-5H-dibenzo[b,d]silole,were synthesized in good yield(>85%)and high molecular weight up to Mn=5.82×10^(4) via direct arylation polymerization(DAr P).All the resultant polymers exhibit moderate bandgap of about 1.80 e V and strong deep red/near-infrared emitting in the solid state.Among them,the PSi TP-based electroluminescence(EL)devices with an architecture of ITO/PEDOT:PSS/PTAA/emitting layer/TPBi/Li F/Al give the best performance with a maximum luminance of 2543 cd/m^(2) at 478 m A/cm^(2).This work expands the application scope of high-performance conjugated polymers which can be synthesized by DAr P.

关键词： Thieno[3 4-b]pyrazine Alternating D-A structure Direct arylation polymerization Conjugated polymer Organic light-emitting diodes

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Transcriptome-based insights into the calcium transport mechanism of chick chorioallantoic membrane

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Food Science and Human Wellness 2022年第2期11卷 383-392页

作者： Qun Huang Ran Yang Qia Wang Hui Teng Hongbo Song Fang Geng Peng Luo School of Public Health The Key Laboratory of Environmental Pollution Monitoring and Disease ControlMinistry of EducationGuizhou Medical UniversityGuiyang 550025China College of Food Science Fujian Agriculture and Forestry UniversityFuzhou 350002China Meat Processing Key Laboratory of Sichuan Province School of Food and Biological EngineeringChengdu UniversityChengduSichuan 610106China

Chorioallantoic membrane(CAM)is responsible for respiratory gas exchange,eggshell calcium transport,embryonic acid-base equilibrium,allantoic ion,and water reabsorption during avian embryonic development.To further understand the timing of CAM gene expression during chick embryonic development,especially the calcium absorption mechanism,transcriptome quantitative comparative analysis was conducted on chick CAM during the embryonic period(E)of 9,13,17,and 20 days.A total of 6378 differentially expressed genes(DEGs)were identified.Functional enrichment analysis of DEGs showed that CAM DEGs were mainly involved in biological processes such as"ion transport regulation","immune response"and"cell cycle".Time series analysis of the differential genes showed that the functional cells of CAM began to proliferate and differentiate at E9 and the calcium content of egg embryo increased significantly at E13.Simultaneously,the observation of the ultrastructure of the eggshell showed that the interstice of the fiber layer was enlarged at E13,and the mastoid layer was partly exposed.Therefore,it is preliminarily inferred that CAM calcium transport starts at E13,and genes such as TRPV6,S100 A10,and RANKL cooperate to regulate calcium release and transport.

关键词： Incubation Chorioallantoic membrane Transcriptome Calcium transport

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Synthesis,Crystal Structure and Photoluminescent Property of a Novel Dy^(3+) Coordination Compound Containing Rare(H_2O)_(22) Clusters

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Chinese Journal of Structural Chemistry 2016年第12期35卷 1980-1986页

作者：叶燕珠吴新建张贤金汪阿恋 Department of Science Research and Training Fujian Institute of Education

A novel Dy^（3＋） coordination compound,（H_2pipz）（H_3O）[Dy（pydc）_3]·11H_2O（1,pipz = piperazine and H_2pydc = pyridine-2,6-dicarboxylic acid）,has been hydrothermally synthesized and characterized by X-ray single-crystal diffraction,elemental analysis. It is interesting that the packing structure of compound 1 contains 22-core water clusters. Compound 1 is extended into a threedimensional supramolecular structure via O···H···O hydrogen bonding interactions. Furthermore,the luminescent property of compound 1 was also investigated.

关键词： Dy3＋ coordination compound crystal structure water clusters luminescent property

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Synthesis, Structure and Property of a Novel Coordination Polymer [Tb(C_7H_3NO_4)(C_6H_4NO_2)(H_2O)]

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Chinese Journal of Structural Chemistry 2014年第12期33卷 1860-1864页

作者：叶燕珠吴新建汪阿恋 Department of Science Research and Training Fujian Institute of Education

A novel terbium(III) coordination polymer [Tb(C7H3NO4)(C6H4NO2)(H2O)] was successfully synthesized hydrothermally and characterized by single-crystal X-ray diffraction. The complex is of monoclinic, space group P21/c with a = 9.2252(11), b = 14.1477(16), c = 10.5134(12) A, β = 95.770(2)°, V = 1365.2(3) A3, Z = 4, Dc = 2.248 g·cm-3, F(000) = 880, the final R = 0.0176 and w R = 0.0411 for 2149 observed reflections with I > 2σ(I). The complex is extended into a three-dimensional network structure with 24-atom rings which are composed of Tb, C and O atoms. The complex displays green fluorescence emission in the solid state at room temperature, which corresponds to 5D4 → 7F5 transition of the Tb(III) ion.

关键词： pyridine-2,5-dicarboxylic acid,terbium,coordination polymer,luminescent property

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Sn-doped induced stable 1T-WSe_(2)nanosheets entrenched on N-doped carbon with extraordinary half/full sodium/potassium storage performance

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Rare Metals 2023年第5期42卷 1557-1569页

作者： Yan-Ru Liu Ze-Wei Lei Ren-Ping Liu Xin-Ye Li Pei-Xun Xiong Yong-Jin Luo Qing-Hua Chen Ming-Deng Wei Ling-Xing Zeng Qing-Rong Qian College of Life Science Fujian Normal UniversityFuzhou350007China Engineering Research Center of Polymer Green Recycling of Ministry of Education College of Environment and ResourcesCollege of Carbon Neutral Modern IndustryFujian Normal UniversityFuzhou350007China fujian Key Laboratory of Pollution Control and Resource Reuse Fuzhou350007China fujian Provincial Key Laboratory of Electrochemical Energy Storage Materials Fuzhou UniversityFuzhou350002China Key Laboratory of Advanced Energy Materials Chemistry Ministry of EducationCollege of ChemistryNankai UniversityTianjin300071China

At present,there have been some reports on the application of metal phase selenide(1T-MSe_(2))in the field of energy storage.In this manuscript,a stable Sn-doped metal phase tungsten selenide(1T-WSe_(2)-Sn)was elaborately fabricated in situ by a simple calcination technique.N-doping was introduced by employing chitosan as precursor and nanoreactor,the Sn-doping induces 1T phase of WSe_(2)and enlarges the layer space to promote the electron/ion transport and structural stability.The optimized 1T-WSe_(2)-Sn electrode delivers prominent cycling lifespan(285 mAh·g^(-1)at 1.0 A·g^(-1)after 900 cycles)along with decent rate capability when applied as an anode of sodium ion batteries(SIBs).The specific capacity was determined to be of 460 mAh·g^(-1)at 0.1 A·g^(-1)after 100cycles.It also displays superior capacity of 183 mAh·g^(-1)at0.5 A·g^(-1)for 200 cycles when paired with Na_(3)V_(2)(PO_(4))_(3)cathode.Applied as the anode for potassium ion batteries(PIBs),it exhibits a satisfactory specific capacity of 345mAh·g^(-1)at 0.1 A·g^(-1)after 50 cycles.

关键词： WSe_(2) Sn-doped Metal phase Sodium/potassium storage

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Conversion of Au(Ⅲ)-polluted waste eggshell into functional CaO/Au nanocatalyst for biodiesel production

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Green Energy & Environment 2022年第2期7卷 352-359页

作者： Jiadi Liu Minghuan Liu Shaoyun Chen Bingqing Wang Jin Chen Da-Peng Yang Shangzhou Zhang Wenxiao Du College of Life Science Yantai UniversityYantaiShandong Province264005China School of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantaiShandong Province264005China College of Chemical Engineering and Materials Science Quanzhou Normal UniversityQuanzhouFujian Province362000China Clinical Center for Molecular Diagnosis and Therapy The Second Affiliated Hospital of Fujian Medical UniversityQuanzhouShandong Province362000China

Developing an environmental-friendly and highly active catalyst in transesterification for biodiesel production is of great importance for a more economic biodisel process.Herein,we reported that waste eggshells were used to adsorb Au(Ⅲ) in water and convert the Au(Ⅲ)-polluted eggshells into the functional nanocatalyst-Ca O/Au for the transesterification reaction between soybean oil and methanol to the preparation of biodiesel.By coupling of Ca O and Au nanoparticles,Ca O/Au nanoparticles showed superior catalytic activity for the transesterification reaction between soybean oil and methanol.An optimum performance was observed over Ca O/Au nanocomposites in a methanol-oil molar ratio at 12:1with catalyst content of 1.0 wt% at 70°C for 3 h.Besides,the catalytic activity of Ca O/Au nanocatalyst was almost unchanged after recycling for 5 times and the yield of biodiesel still kept at 88.9%.The proof-of concept study provided us a sustainable method for utilization of waste eggshells to remedy the metal ions-polluted wastewater and the synthesis of functional nanocomposite for biodiesel production,show great potential application of waste eggshell in adsorption and catalytic reactions.

关键词： process Au(Ⅲ) catalyst

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Microstructure and mechanical properties of Gd-modified AZ80 magnesium alloys

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Rare Metals 2022年第12期41卷 4194-4200页

作者： Nan Jiang Ling-Gang Meng Xing-Guo Zhang Lei Chen Can-Feng Fang Hai Hao School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China

The micros true ture and mechanical properties of AZ80 alloy with different Gd contents were investigated.The results reveal that a minor addition of Gd could lead to a change in the type of second phase particles from Al-Mn to Al-Gd-Mn,and the primary rare earth phase is Al8GdMn4instead of Al2Gd in the AZ80-0.3Gd alloy.New strip-like Al3Gd and block-shaped Al2Gd phases are formed successively with the increase of Gd content.Al2Gd phase becomes the dominating rare earth phase in AZ80-2.0Gd and AZ80-4.0Gd alloys.Tensile test indicates that the mechanical properties are improved obviously with a proper Gd content.However,excessive Gd addition results in the decrease of mechanical properties due to the formation of coarse block-shaped Al2Gd phase.AZ80-0.9Gd alloy exhibits the optimal mechanical properties among all the experimental alloys,in which the ultimate tensile strength(UTS),yield strength(YS)and elongation are 210,130 MPa and 8.2%,respectively.

关键词： AZ80 alloy Gd Microstructure Mechanical properties

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Synthesis, Structure and Luminescent Property of an Europium(Ⅲ) Coordination Polymer

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Chinese Journal of Structural Chemistry 2014年第11期33卷 1649-1654页

作者：叶燕珠林深吴新建 Department of Science Research and Training Fujian Institute of Education College of Chemistry and Chemical Engineering Fujian Normal University

A novel europium（Ⅲ） coordination polymer, [Eu3（pydc）3（SO4）（H2O）5（ox）0.5]·3H2O（1, H2ox = oxalic acid, H2 pydc = pyridine-2,6-dicarboxylic acid）, has been synthesized hydrothermally from the self-assembly of lanthanide ions（Eu3＋） with the flexible oxalic acid and the rigid pyridine-2,6-dicarboxylic acid ligands, respectively. It crystallizes in the triclinic system, space group P1 with a = 11.225（4）, b = 12.390（5）, c = 13.752（5）A, α = 89.228（7）, β = 71.142（6）, γ = 75.552（6）°, Dc = 2.317 g/cm^3, μ = 5.480 mm^-1, F（000） = 1150, Z = 2, the final R = 0.0351 and w R = 0.0949 for 8782 observed reflections with I 〉 2σ（I）. Structural analysis reveals that complex 1 exhibits a three-dimensional metal-organic framework via π-π stacking interactions. In addition, complex 1 displays a red fluorescence emission in the solid state at room temperature, which corresponds to the 5D0 → 7F2 transition of Eu3＋ ions.

关键词： coordination polymer,lanthanide,luminescent property

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Green rapid synthesis of Cu_(2)O/Ag heterojunctions exerting synergistic antibiosis

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Chinese Chemical Letters 2022年第1期33卷 308-313页

作者： Feiyue Hu Bo Song Xiaohan Wang Shen Bao Siyang Shang Shupei Lv Bingbing Fan Rui Zhang Jingguo Li School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China People's Hospital of Zhengzhou University Henan Provincial People's HospitalZhengzhou 450003China School of Material Science and Engineering Luoyang Institute of Science and TechnologyLuoyang 471023China

Semiconductor-noble metal composite has become a research focus due to its superior performance compared with its respective component.Although various methods have been developed to synthesize semiconductor-noble metal heterostructures,most of them are relatively complex multistep and use toxic reactants of high cost and risk.In this work,a series of Cu_(2)O/Ag heterojunctions were quickly prepared in one step via simple microwave-assisted green route.XRD,SEM,TEM,EDS,XPS,etc.were used to characterize obtained products,and the results indicate a Cu_(2)O/Ag metal-semiconductor heterojunction in micro-nano size was fabricated successfully.In addition,antibacterial behavior of Cu_(2)O/Ag heterojunctions against E.coli and S.aureus were investigated.Owing to the synergistic effect of Cu_(2)O and Ag,the heterojunction exhibits much better antibacterial performance than the pristine Cu_(2)O does.This work provides new insights into the green design and fabrication of surface-modified Cu_(2)O hybrid multifunctional materials for antibacterial applications.

关键词： Cu_(2)O/Ag heterojunctions Green synthesis Microwave-assisted Antibacterial Synergistic effect

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