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Spatiotemporal evolution of C3/C4 vegetation and its controlling factors in southern ch.na since the last glacial maximum

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Science ch.na Earth Sciences 2019年第8期62卷 1256-1268页

作者： Linlin CUI jianfang HU Xu WAnG Institute of Geology and Geophysics Chinese Academy of SciencesBeijing100029China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Guanzhou Institute of Geochemistry Chinese Academy of SciencesBeijing510640China

To date, few research have been reported on the evolution of C3/C4 vegetation in southern ch.na, and the main mech.nism influencing the evolution of C3/C4 vegetation is unclear. That makes it difficult for researchers to understand the competition mech.nism of C3 and C4 plants under different climate environments and its relationship with the climate factors. It is also not conducive for researchers to assess the influence of future climate ch.nge on regional C3/C4 vegetation. Exactly, C3/C4 vegetation ch.nge in the regional-scale will have a significant impact on the global carbon cycle and agricultural ***, it is especially important to reconstruct the evolutionary history of C3/C4 vegetation in southern ch.na and clarify the influencing mech.nism of climate ch.nge. In this study, we systematically analyzed stable carbon isotope(δ13 C) of the longchain n-alkanes in sediment samples from eight lakes and four peat profiles in southern ch.na, to reconstruct the spatiotemporal evolution of C3/C4 vegetation in these regions since the Last Glacial Maximum(LGM) and to investigate the climate factors that affect the C4 plant abundance ch.nge in the research area. The integrated long-chain n-alkane(C27–C33) stable carbon isotope results of samples from Zhanjiang Huguangyan Maar Lake, Xingyun Lake, Lugu Lake and Dingnan peat showed that, from the LGM to the Early Holocene, C4 plant relative abundance exhibited a gradually increasing trend from 21% to 34%. In the Middle Holocene, the C4 plant abundance significantly declined and reached a lowest value of 10%. In space, the C4 plant abundance generally exhibited a gradually declining trend from south to north in the LGM and the Early Holocene, while it showed an opposite trend in the Holocene Climate Optimum(6.0 cal ka BP). It reflected that the main influencing factor on C4 plants spatial distribution was ch.nging from temperature to precipitation. This study indicated that temperature was the dominant facto

关键词： Stable carbon isotope Long-chain n-alkanes C3/C4vegetation Last Glacial Maximum Holocene Climate Optimum period

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Synthesis and Crystal Structure of 2-chloromethyl-1H-benzimidazole nitrate, [Clch_2(C_7H_6n_2)]nO_3

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ch.nese Journal of Structural chemistry 2003年第4期22卷 382-386页

作者： jianfang-Fang BEIFeng-Li WAnGXin LULu-De newMaterials&FunctionCoordinationchemistryLaboratory QingdaoUniversityofScienceandTechnologyQingdao266042China MaterialschemistryLaboratory NanjingUniversityofScience&TechnologyNanjing210094China

The title compound [Clch2(C7H6n2)]nO3 has been prepared and characterized by elemental analysis and X-ray studies. It crystallizes in the monoclinic system, space group P21/n with a = 7.4189(3), b =15.3064(6), c = 9.2657(3) ? b = 102.449(2)? C8H8Cln3O3, Mr = 229.62, V = 1027.44(7) 3, Z = 4, Dc = 1.484 g/cm3, F(000) = 472, = 0.363 mm-1, R = 0.0671 and wR = 0.1546. The crystal structure consists of discrete 2-chloromethyl-1H-benzimidazole cations and nO3- anions. The benzimidazole ring with the conjunction carbon atom C(1) is fairly planar, with the deviation from the least plane through the ring atoms is smaller than 0.010(3) ? The analytical results of crystal structure show that three different non-covalent interactions in the compound, nH…O intermolecular hydrogen bonds, ch…O interaction and p-p stacking interaction, play an important role in the crystal packing.

关键词： crystal structure benzimidazole cation hydrogen bond network

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Synthesis, Crystal Structure and characterization of α-(1-Benzimidazolyl)-hypnone Cobalt(Ⅱ) Complex: [CoCl(C_7H_5n_2ch_2COPh)_4]Br

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chemical Research in ch.nese Universities 2005年第4期21卷 419-422页

作者： jianfang-fang SUnPing-ping XIAOHai-lian ZHAOPu-su newMaterials＆FunctionCoordinationchemistryLaboratory QingdaoUniversityofScienceandTechnologyQingdao266042P.R.China

The crystal structure of [CoCl(C_7H_5n_2ch_2COPh)_4]Br has been determined by means of X-ray crystallography. The molecular structure consists of a discrete [CoCl(C_7H_5n_2ch_2COPh)_4]+ cation and one Br- anion. In the [CoCl(C_7H_5n_2ch_2COPh)_4]+ cation, the coordination geometry of the central Co atom is square-pyramidal with four tertiary n atoms of benzimidazole from four α-(benzimidazol-1-yl)-hypnone ligands in the basal position and one chloride anion in the apical position. In the solid state, [CoCl(C_7H_5n_2ch_2COPh)_4]+ and Br- anion possess intermolecular and intramolecular interactions, which stabilize the crystal structure. The characterization of the title compound were also carried out by using elemeutal analysis, FTIR, UV spectrometries and TG-DSC.

关键词： α-(1-Benzimidazolyl)-hypnone ligand Cobalt(Ⅱ) complex Mixed Cl^- and Br^- anion TG-DSC

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Synthesis, Crystal Structure and Spectrometry Study of chiral n-Ethyl-n'-(2',3',4',6'-tetra-O-acetyl-β-D-glycosyl)-thiocarbamide

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ch.nese Journal of Structural chemistry 2003年第5期22卷 563-567页

作者： jianfang-Fang XIAOHai-Lian SUnPing-Ping ZHAOPu-Su newMaterials&FunctionCoordinationchemistryLaboratory QingdaoUniversityofScienceandTechnologyQingdao266042China MaterialschemistryLaboratory NanjingUniversityofScienceandTechnologyNanjing210094China

The structure of chiral n-ethyl-n-(2,3,4,6-tetra-O-acetyl-b-D-glycosyl)-thio- carbamide was determined by X-ray diffraction method. It crystallizes in the monoclinic system, space group P21 with a = 7.6560(15), b = 10.311(2), c =14.181(3) ? b =100.88(3), C17H26n2O9S, Mr = 434.46, V = 1099.3(4) ?, Z = 2, Dc = 1.312 g/cm3, F(000) = 460, m = 0.196 mm-1, R = 0.0704 and wR = 0.1655. The total independent reflections were 5098, of which 1875 were observed with I ≥2s(I). The hexopyranosyl ring adopts a chair conformation. All the ring substituents are in the equatorial positions. The acetoxylmethyl group is in the gauche-gauche conformation. The S atom is in synperiplanar conformation, while the nCnC linkage is antiperiplanar. X-ray analysis shows that the absolute configuration of the chiral carbon atom at C(1) was proved to be b-form. The 1H nMR spectra and IR are in good agreement with the result of crystallography analysis. The nH…O intermolecular hydrogen bonds link the molecules into infinite chains connected by ch…O interactions.

关键词： crystal structure thiocarbamide b-D-glycopranosyl derivation hydrogen bonds chair conformation

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Synthesis and Crystal Structure of a new Dinuclear Manganese(Ⅱ) Manganese(Ⅲ) Complex of a Macrocyclic Ligand

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chemical Research in ch.nese Universities 2004年第6期20卷 725-728页

作者： jianfang-fang XIAOHai-lian XULiang-zhong PAnGLei newMaterials＆FunctionCoordinationchemistryLaboratory QingdaoUniversityofScienceandTechnologyQingdao266042P.R.China

A mixed-valence dinuclear manganese complex, [Mn ⅡMn ⅢL](ClO 4)·1/2MeOH, where L is a macrocyclic ligand derived from the cyclocondensation of sodium 2,6-diformyl-4-methylphenolate with n,n-bis(2-aminoethyl)-2-hydroxybenzyl amine, was obtained and its structure was determined by X-ray diffraction. The orange crystal is a monoclinic system with space group P2 1/c and lattice parameters a=1.1617(4), b=1.4005(3), c=1.4641(3) nm, β=113.03(2)°, and Z=2. The crystal structure shows that each pendant-arm is bonded in a bidentate fashion to the adjacent metal atom and that both the arms are on the same side of the macrocycle. The two Mn atoms are bridged by two μ 2-phenoxy oxygen atoms of the tetra-imine macrocycle, and each Mn atom, locating in a trigonal prismatic coordination environment(n 3O 3), is six-coordinated by the two imine nitrogen atoms, one tertiary nitrogen atom and a pendant phenol moiety apart from the two oxygen atoms.

关键词： Dinuclear manganese complex Macrocyclic compound Crystal structure

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nEW PRECISIOn PIEZOELECTRIC STEP ACTUATOR

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ch.nese Journal of Mech.nical Engineering 2006年第2期19卷 212-216页

作者： LIU jianfang YAnG Zhigang FAn Zunqiang ch.nG Guangming College of Mech.nical Engineering Jilin UniversityChangchun 130025 China

A new precision piezoelectric actuator is proposed to improve its drive capabilities. The actuator is based on the piezoelectric technology. It adopts the principle of bionics and works with a new method of stator initiative anchoring/loosen and a distortion structure of double-side thin flexible hinge. It solves the problem of anchoring/loosen, frequency, journey, resolution and velocity. The experiment shows that the new linear piezoelectric actuator works with high frequency （100 Hz）, high speed （502 μm/s）, large travel （〉10 mm）, high resolution （0.05 μm） and high load （100 n）. This kind of new piezoelectric actuator will be applied for large travel and high resolution driving device, optics engineering precision positioning and some micromanipulation field.

关键词： Piezoelectric step actuator Stator outside anchoring/loosen Precision Double-side thin flexible hinge Large travel

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Effect of wind-current interaction on ocean response during Typhoon KAEMI(2006)

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Science ch.na Earth Sciences 2013年第3期56卷 418-433页

作者： LIU Lei FEI jianfang ch.nG XiaoPing HUAnG XiaoGang PLA University of Science and Technology

The Weather Research and Forecasting （WRF） model, the Princeton Ocean Model （POM）, and the wave model （WAVEWATch III） are used to develop a coupled atmosphere-wave-ocean model, which involves different physical pro- cesses including air-forcing, ocean feedback, wave-induced mixing and wave-current interaction. In this paper, typhoon KAEMI （2006） has been examined to investigate the effect of wind-current interaction on ocean response based on the coupled atmosphere-ocean-wave model, i.e., considering the sea surface currents in the calculation of wind stress. The results show that the wind-current interaction has a noticeable impact on the simulation of 10 m-winds. The model involving the effect of the wind-current interaction can dramatically improve the typhoon prediction. The wind-current interaction prevents excessive momentum fluxes from being transferred into the upper ocean, which contributes to a much smaller turbulence kinetic energy （TKE）, vertical diffusivity, and horizontal advection and diffusion. The Sea Surface Temperature （SST） cooling induced by the wind-current interaction during the initial stage of typhoon development is so minor that the typhoon intensity is not very sen- sitive to it. When the typhoon reaches its peak, its winds can disturb thermocline, and the cold water under the thermocline is pumped up. However, this cooling process is weakened by the wind-current interaction, as ocean feedback delays the decay of the typhoon. Meanwhile, the temperature below the depth of 30 m shows an inertial oscillation with a period about 40 hours （-17°n） when sudden strong winds beat on the ocean. Due to faster currents, the significant wave height decreases as ignoring the wind-current interaction, while this process has a very small effect on the dominant wave length.

关键词： coupled atmosphere-wave-ocean model typhoon wave induced mixing SST cooling wave state

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Four Coordination Polymers Assembled with a new Biscarboxyl-functionalized Schiff Base Ligand

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chemical Research in ch.nese Universities 2018年第5期34卷 839-843页

作者： KAnG Dawei XIE Jingjing LIU Yingying MA jianfang Key Laboratory of Polyoxometalate Science Department of Chemistry Northeast Normal University Changchun 130024 P. R. China Inner Mongolia Key Lab of chemistry of natural Products and Synthesis of Functional Molecules College of chemistry and chemical Engineering lnner Mongolia University for the Nationalities Tongliao 028000 P. R. China

Based on a new biscarboxyl-functionalized Schiff base ligand 1,2-cyclohexanediamino-n,n＇-bis[3- methoxyl-5-（p-carboxyl-phenylazo）] salicylidene（H4L）, four polymers, [（ch3）：nH2]2.[Mn3（L）2（H2O）4]·2DMF（CP1）, [Fe2（L）（H2O）（DMF）]（CP2）, [（ch3）2nG2].[Cu（HL）]·H2O（CP3） and [ni2（L）（teta）]·2DMF·H2O（CP4）, have been synthesized（teta=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane）. In CPI, both of the internal [n202] pocket and the external carboxylate groups of L＊- anion are ligated by Mn2＋ ions, and the structure displays a layer. In CP2, the Fe^2＋ cations are linked by L4- anions to form a binuclear double chain. CP3 displays a [Cu2（I-IL）2] dimer. In CP4, the ni^2＋ ions are connected by L4- anions to form a chain. The structures are further linked by hydrogen bonds to form 2D or 3D supramolecular architectures, respectively. CP1 exhibits adsorption ability to three organic dyes.

关键词： Coordination polymer Schiffbase Carboxylic acid Dye adsorption

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Development and optimized pairing of mouse monoclonal antibodies for detecting hemagglutinin in novel H7 subtype influenza viruses

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Science ch.na(Life Sciences) 2020年第2期63卷 279-289页

作者： Huijuan Wang jianfang Zhou Dayan Wang Baoying Huang Wenjie Tan nHC Key Laboratory of Biosafety National Institute for Viral Disease Control&PreventionChinese Center for Disease Control and PreventionChina CDCBeijing 102206China

The H7 subtype avian influenza threatens public health with respect to poultry and ***,a specific and sensitive diagnostic test is essential for the management of H7 subtype influenza *** this study,five mouse monoclonal antibodies(mAbs)against hemagglutinin(HA)of influenza A/Anhui/1/2013(H7n9)were produced and characterized by the Western blot,immunofluorescence,and hemagglutination inhibition *** five specific mAbs reacted with the HA protein of H7n9 but not with that of H1 n1,H3 n2,or H5 *** the combination arrays of capture and detection antibodies,the matched pair m Abs(1 C4-coated and 2 D7-labeled)were selected and employed in a double-antibody sandwich ELISA(DASELISA).Detection limits of the sandwich ELISA were 0.45 ng mL^–1 for the HA protein derived from A/Anhui/1/2013(H7n9);or 1 and 2 HA units/50μL for A/Anhui/1/2013(H7n9)and A/GD/17 SF003/2016(H7n9),*** anti-HA mAbs against subtype H7 and the novel DAS-ELISA provide a valuable approach for specific detection of the H7 subtype influenza virus and quantification of its HA protein,especially for the novel epidemic H7n9.

关键词： influenza A H7 subtype hemagglutinin monoclonal antibodies sandwich ELISA

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Hydrothermal Synthesis and X-ray characterization of Silver(I) Complex:Diacetylthiocarbamide Silver(I) nitrate, [Ag(ch_3COnHC(S)nH_2)_2](nO_3)

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ch.nese Journal of Structural chemistry 2004年第5期23卷 486-489页

作者： jianfang-Fang XIAOHai-Lian ZHAOPu-Su MaterialschemistryLaboratory NanjingUniversityofScienceandTechnologyNanjing210094China newMaterials＆FunctionCoordinationchemistryLaboratory QingdaoUniversityofScienceandTechnologyQingdao266042China

The title compound [Ag(ch3COnHC(S)nH2)2](nO3) has been prepared by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. It crystallizes in mo-noclinic, space group P21/c with Mr = 406.20 (C6H12Ag n5O5S2), a = 12.0680(6), b = 6.8056(5), c = 18.0173(1) ? b = 111.383(4), V = 1377.9(2) 3, Z = 4, Dc = 1.958 g/cm3 , F(000) = 808, = 1.789 mm-1, R = 0.0361 and wR = 0.1015. Of 4185 reflections ((2)max = 55.00?, 3147 were unique (Rint = 0.0174) and 2820 with I > 2(I) were used to solve the structure. The silver(I) atom adopts V-shape geometry with the AgS bond distance of 2.4271(7) and 2.7229(9) , respectively. Seven atoms of one acetylthiocarbamide ligand are coplanar, while only four atoms of another acetylthio-carbamide ligand are fairly planar. The [Ag(ch3COnHC(S)nH2)2]+ cation and nitrate anion nO3- are connected by hydrogen bonds to form a three dimensional hydrogen bonding network..

关键词： crystal structure hydrothermal method diacetylthiocarbamide nitrate silver(I) hydrogen bond network

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