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西藏高寒草原湿润度梯度下植物群落特征空间格局及其驱动因子

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生态学报 2024年第5期44卷 1996-2007页

作者：任世杰宋朝阳林长存刘思奇刘涛张雪梅纪宝明北京林业大学草业与草原学院北京100083

西藏高原是中国高寒生态系统类型和生物多样性均聚集的区域之一,其中以高寒典型草原和高寒草甸草原为主生态系统类型,但其系统活力、组织力和恢复力均较弱,容易受到全球气候变化的影响,表现出极强的脆弱性。目前青藏高原草地生态系统植... 详细信息

西藏高原是中国高寒生态系统类型和生物多样性均聚集的区域之一,其中以高寒典型草原和高寒草甸草原为主生态系统类型,但其系统活力、组织力和恢复力均较弱,容易受到全球气候变化的影响,表现出极强的脆弱性。目前青藏高原草地生态系统植物群落分布状况与其变化规律以及对各种环境因子的反应研究多集中于站点尺度或样带尺度,但研究结果尚有较大的不确定性。研究于西藏地区沿着不同的湿润度梯度选择14处高寒草原区样地,通过植物群落调查、土壤理化性质分析,探索草本植被群落空间格局对气候因子响应特征及其主要驱动因子,其结果为青藏高原天然草地保护和可持续利用提供基础科学数据支撑。结果表明:(1)研究区内依据湿润度分区可分为干旱区、微干区、微润区和湿润区4类;研究区1971—2021年的气候数据分析发现,北部的干旱程度在逐渐减轻,而南部在1991—2010阶段干旱化趋势逐渐加强,整个研究区的湿润度指数均在下降;(2)植物群落调查发现不同植物功能群的变化各有差异,莎草科地上生物量随湿润度增加而增加,杂类草地上生物量呈现单峰趋势,而其他植物功能群无明显规律;湿润度较高的微润区间植物群落的Shannon-Wiener指数、Simpson指数、丰富度指数、均匀度指数均高于其他湿润度区间;(3)土壤理化性质分析发现高湿润度区域的土壤含水量、全氮、硝态氮、铵态氮、速效磷含量均为最高;对各环境因子与植物群落特征指标进行相关性、主成分分析后构建结构方程模型,发现直接影响西藏高寒草原植物群落特征变化因子为湿润度,土壤含水量和土壤pH,且都表现为显著的负效应(P<0.05),同时湿润度对土壤含水量和土壤全量养分产生了显著的正向影响(P<0.05),进而影响着西藏高原高寒草原不同植物功能群的分布、多样性、地上生物量。

关键词：西藏高寒草原湿润度植物群落特征气候因子土壤理化性质

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Synthesis of two lanthanide clusters Ln^(Ⅲ)_(4)(Gd_(4) and Dy_(4)) with [2×2] square grid shape:Magnetocaloric effect and slow magnetic relaxation behaviors

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Journal of Rare Earths 2021年第9期39卷 1082-1088页

作者： Chunying Xu Zhilei Wu Chenjuan Fan Lili Yan Wenmin Wang baoming ji Henan Key Laboratory of Function-Oriented Porous Materials.College of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyang 471934China College of Chemistry and Environmental Science Hebei UniversityBaoding 071002China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University.Tianjin 300071China

Two isostructural tetranuclear lanthanide clusters named [Ln_(4)(L)_(4)(CH_(3) O)_(4)]·CH_(3) OH(Ln=Gd(Ⅲ) for 1,Dy(Ⅲ) for 2,H_(2) L=N’-(2-hydroxy-3-methoxybenzylidene)-6-(hydroxymethyl) picolinohydrazide) were successfully isolated by using a polydentate Schiff based ligand and Ln(Ⅲ) nitrate *** structures of 1 and 2 were characterized by X-ray structural analyses,they are held by four double deprotonated ligands L2-.In them all the lanthanide ions are eight-coordinated and distributed over four vertices of a parallelogram,presenting a Ln4 cluster with a strict [2 × 2] square grid *** details of magnetic analysis show that 1 displays weak anti-ferromagnetic exchange between neighboring Gd(Ⅲ) ions through carboxylate oxygen and methanol oxygen ligand ***,1 exhibits significant magnetocaloric effect with the maximum entropy change-ΔSm value of 28.5 J/(kg K) for ΔH=7.0 T at 2.0 *** compound 2,remarkable slow magnetic relaxation behaviors are observed in the presence of zero magnetic field with τ0=1.02 × 10^(-6) s and energy barrier ΔE/kB=43.24 K.

关键词： Lanthanide clusters [2×2]square grid Anti-ferromagnetic couplings Magnetocaloric effect Slow magnetic relaxation Rare earths

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Structural Study on Four co-Crystals of N-Containing Heteroaromatics with Iodofluorobenzene

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Chemical Research in Chinese Universities 2015年第1期31卷 84-90页

作者： ji baoming DENG Dongsheng WANG Weizhou WANG Ke HE Mengli College of Chemistry and Chemical Engineering Luoyang Normal University Luoyang 471022 P. R. China

N-Containing heteroaromatics 1,2,4,5-tetra（pyridin-3-yl）benzene[1,2,4,5-T（3-PY）B] and 1,2,4,5-tetra（pyridin-4-yl）benzene[1,2,4,5-T（4-PY）B] were each co-crystallized with 1,2-diiodo-tetrafluoro-benzene（1,2-DITFB）, or 1,4-diiodo-tetrafluoro-benzene（1,4-DITFB）, respectively, generating four co-crystals, namely, （1,2-DITFB）4 [1,2,4,5-T（3-PY）B]（1）, （1,2-DITFB）4.[ 1,2,4,5-T（4-PY）B]（2）, （1,4-DITFB）2.[1,2,4,5-T（3-PY）B]-CHCI3（3）, and （1,4-DITFB）-[1,2,4,5-T（4-PY）B]2CHCI3（4）. This study takes aim at providing an insight into the relative importance of fundamental solid state halogen bonding interactions（i.e., halogen..N, halogen,..halogen, and halogen...π in systems. The effects of the donor and acceptor on supramolecular assembly and the crystal structure determined interactions were discussed. The N...I halogen bonds are the main directing interactions responsible for the observed structures. In compounds 1 and 2, the donors exhibited lower-than-expected supramolecular connectivity. In spite of this, co-crystal 2 exhibits polymeric structures consisting of infinite one-dimensional（1D） double-zigzag chains of alternating electron donor and acceptor. The basic structure of co-crystals 3 and 4 is also infinite 1D chain. Therefore, the ID halogen bonded supramolecular assemblies can be obtained by matching the appropriate donor and acceptor.

关键词： Self-assembly co-Crystal Halogen bond Crystal structure

Efficient and stable deep-blue electroluminescent device based on a novel pyrene derivative with highly twisted structure

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Efficient and stable deep-blue electroluminescent device bas...

河南省化学会2016年学术年会

作者： Zhiqiang Wang Chen Xu baoming ji College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials Luoyang Normal University

A novel pyrene derivative 1-(3,5-diphenyl)phenyl-6-[2-(9-phenyl-9H-carbazol-3-yl)phenyl]pyrene(Py PC) was successfully designed and synthesized, the structure of this compound was characterized by H NMR spectrum, 13 CNMR spectrum, mass spectrum and *** chemistry calculation results show that the compound Py PC has a highly twisted noncoplanar structure. Py PC show an efficient deep-blue emission both in solution and as solid film, and has high thermal stability. A non-doped electroluminescent device ITO/NPB(20 nm)/T CTA(10 nm)/ Py PC(30 nm)/TPBI(40 nm)/Li F(1.5 nm)/Al(100 nm) was fabricated by vacuum vapor deposition using Py PC as emitting layer. This device exhibited an efficient deepblue emission with a maximum external quantum efficiency of 3.72 % and a CIE coordinate of(0.16, 0.09). In addition, this device has high stability, the electroluminescence spectra and CIE coordinates are almost identical under different luminance from 100 cd/m to 1500 cd/m,and the external quantum efficiency remains 3.46 % at a luminance of 1500 cd/m.

关键词： OLEDs Deep-blue materials Pyrene derivative Non-doped device

Porous amine-functionalized coordination polymers as cooperative and size-selective catalysts for acetylation of phenols

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Porous amine-functionalized coordination polymers as coopera...

河南省化学会2016年学术年会

作者： Dongsheng Deng Hui Guo jingzhi Yang baoming ji College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials Luoyang Normal University

Amine-functionalized porous coordination polymers(PCPs) are a burgeoning class of solid catalysts with uniform catalytic sites and open channel structures for shape- and size-selective reactions. As part of our extensive investigations of amine-based porous coordination frameworks, we reported herein on the catalytic capacity of Zn(L)(aip)(H2aip = 5-aminoisophthalic acid, L = N,N-di(pyridine-4-yl)biphenyl-4,4’-dicarboxamide) towards acetylation of various phenols with varying electronic properties and reactivities. In particular, the unique structural features of this PCPs, including non-coordinated amine groups as accessible catalytic sites and suitable channel size and shape, endow the PCPs with all of the desired features for the PCPs-catalyzed acetylation reactions, including heterogeneous catalyst,high catalytic activity, robustness, and excellent cooperative and size-selectivity.

关键词： porous coordination polymers heterogeneous catalysis cooperative catalyst acetylation reaction

Unimodal productivity-biodiversity relationship along the gradient of multidimensional resources across Chinese grasslands

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National Science Review 2022年第12期9卷 90-103页

作者： Yanfen Wang jianqing Du Zhe Pang Yali Liu Kai Xue Yann Hautier Biao Zhang Li Tang Lili jiang baoming ji Xingliang Xu jing Zhang Ronghai Hu Shutong Zhou Fang Wang Rongxiao Che Di Wang Chaoting Zhou Xiaoyong Cui Nico Eisenhauer Yanbin Hao College of Resources and Environment University of Chinese Academy of Sciences State Key Laboratory of Tibetan Plateau Earth System Environment and Resources Chinese Academy of Sciences Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of Sciences School of Grassland Science Beijing Forestry University Ecology and Biodiversity Group Department of BiologyUtrecht University Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Life Sciences University of Chinese Academy of Sciences School of Ecology and Environmental Sciences Yunnan University Institute of Biophysics Chinese Academy of Sciences Department of Medicine New York University Grossman School of Medicine Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of Sciences College of Life Sciences University of Chinese Academy of Sciences German Centre for Integrative Biodiversity Research (iDiv) Institute of Biology Leipzig University

Resources can affect plant productivity and biodiversity simultaneously and thus are key drivers of their relationships in addition to plant-plant ***,most previous studies only focused on a single resource while negle cting the nature of resource *** we integrated four essential resources for plant growth into a single metric of resource diversity(RD) to investigate its effects on the productivity-biodiversity relationship(PBR) across Chinese *** showed that habitats differing in RD have different PBRs—positive in low-resource habitats,but neutral in medium-and high-resource ones—while collectively,a weak positive PBR was observe ***,when excluding direct effects of RD on productivity and biodiversity,the PBR in high-resource habitats became negative,which leads to a unimodal instead of a positive PBR along the RD *** integrating resource effects and changing plant-plant interactions into a unified framework with the RD gradient,our work contributes to uncovering underlying me chanisms for inconsistent PBRs at large scales.

关键词： productivity–biodiversity relationship resource diversity plant strategies grassland

一类具有C_2对称性的轴手性马来酰亚胺类化合物的合成

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有机化学 2017年第10期37卷 2685-2689页

作者：符立言吉保明杜晨霞洛阳师范学院化学化工学院洛阳471022 郑州大学化学与分子工程学院郑州450001

以廉价易得的顺丁烯二酸酐和(R)-1,1'-联二萘酚(BINOL)为起始原料,通过Williamson醚合成法、Suzuki偶联反应、脱保护基等6步反应,以6.2%~16%的总收率合成了一类具有C_2对称性的轴手性酰亚胺类化合物,并通过~1H NMR,^(13)C NMR,HRMS,IR... 详细信息

以廉价易得的顺丁烯二酸酐和(R)-1,1'-联二萘酚(BINOL)为起始原料,通过Williamson醚合成法、Suzuki偶联反应、脱保护基等6步反应,以6.2%~16%的总收率合成了一类具有C_2对称性的轴手性酰亚胺类化合物,并通过~1H NMR,^(13)C NMR,HRMS,IR等手段对其结构进行了表征.

关键词：酰亚胺联萘酚有机合成手性

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Prediction of the Interaction Parameter by the Solubility Parameter for Polyglycolic Acid

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Prediction of the Interaction Parameter by the Solubility Pa...

河南省化学会2016年学术年会

作者： Siye Tang Feng Liu Ye Wang Xinxiang Cao baoming ji College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials Luoyang Normal College

The solvency power of polyglycolic acid was studied using 36 solvents. The Hansen three-dimensional solubility parameters and total parameter of polyglycolic acid were obtained by an optimization *** values of δ, δ, δ and δ for polyglycolic acid were obtained as 17.35(MPa)1/2, 8.66(MPa)1/2, 9.87(MPa)1/2 and 21.76(MPa)1/2. The optimization method is superior to the traditional experimental method because it considers the nonsolvent data also as a part of the procedure. The values of the interaction parameter and the solubility parameter "distance" between polyglycolic acid and 36 solvents have been calculated. The results of the interaction parameters accord well with the standard of complete miscibility suggested by Flory–Huggins. For the commercial polyglycolic acid used in this paper, all the data are reported for the first time.

关键词： polyglycolic acid solubility parameters interaction parameter

Two new deep-blue emitting anthracene derivatives: Synthesis,properties and non-doped electroluminescent devices

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Two new deep-blue emitting anthracene derivatives: Synthesis...

河南省化学会2016年学术年会

作者： Xiaojuan Sun Zhiqiang Wang Chen Xu baoming ji Zhiqiang Zhang Liancai Xu College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials Luoyang Normal University Department of Material and Chemical Engineering Zhengzhou University of Light Industry

Two new anthracene derivatives 9,10-bis(2-biphenyl)anthracene(BBPA) and 9,10-bis[2-(α-naphthyl)phenyl]anthracene(BNPA) were synthesized by Suzuki coupling reaction and characterized by 1H NMR,mass spectrum and elemental analysis. Quantum chemistry calculations show that these compounds have non-coplanar structures and their photophysical properties are controlled by the anthracene *** of these compounds exhibit high-efficiency blue emission in CHCl solutions. The emission spectrum of BBPA as solid film is obviously broader than that measured from CHCl solution, while the emission spectrum of BNPA as solid film does not broaden compared to that acquired from CHCl solution. Two deep-blue non-doped electroluminescent devices were fabricated employing BBPA or BNPA as emitting layer. Device based on BBPA exhibits a maximum external quantum efficiency of 2.48 % and a CIE coordinate of(0.16, 0.09), and the device based on BNPA acquired a maximum external quantum efficiency of 2.68 % and a CIE coordinate of(0.15, 0.07). In addition, both of these devices show low turn-on voltage and high stability.

关键词： Electroluminescence Deep-blue materials Anthracene derivatives Non-doped devices