Synthesis and fluorescent properties in complexes of Eu( Ⅲ), Tb( Ⅲ), and Sm( Ⅲ) with β-diketone and 2,2′-bipyridine

Three new rare earth ternary complexes, RE(PB)_3bpy (RE=Sm^(3+) , Eu^(3+) , and Tb^(3+) ), were synthesized by the reaction of 1-(p-phenylethynyl- phenyl)-1,3-butanedione (HPB) and 2,2′-bipyridine (bpy) with rare earth chloride RECl_3 , respectively, in alcohol solution. The compositions were characterized by means of infrared (IR) spectra, chemical analysis, elemental analysis, and thermodynamic analysis. Luminescent properties of the three complexes were studied. At room temperature, under UV light excitation, the Sm^(3+) , Eu^(3+) , and Tb^(3+) complexes exhibit characteristic emission of the central ions. The fluorescence spectra show that the fluorescence emission intensity of Eu^(3+) complex is the strongest. The narrow strongest emission band of Eu^(3+) complex is considered to be a valuable material with bright red fluorescence.

Crystal Structure and Luminescence Property of Lanthanide Complexes with 2-Fluorobenzoic Acid and 2,2′-Bipyridine

The two compounds of [Ln（2-FBA）3·2,2＇-bpy ]2（2-FBA = 2-fluorobenzoato, 2,2＇-bpy = 2,2＇-bipyridine, Ln = Eu（1 ）, Dy（2）） were synthesized and their structures were determined by X-ray diffraction method. Crystallized complexes 1 and 2 are isomorphous, monoelinie system with P21/n space group. The two complexes are binuclear molecule with an inversion center. The two lanthanide ions are linked by four bridged 2-FBA ligands and each lanthanide ion is further bonded to one chelated bidentate 2-FBA ligand and one 2,2＇-bipyridine molecule. The coordination number of metal ion is eight. The europium complex exhibits strong red fluorescence. ^5D0→^7Fj（j = 1 - 4） transition emission of Eu^3＋ ion was observed.

Synthesis,crystal structure and fluorescence of a new europium complex with 2-bromobenzoate and 2,2'-bipyridine

A new complex of {[Eu2(2-BrBA)6(2,2’-bpy)2]2·CH3CH2OH·H2O} (2-BrBA=2-bromobenzoate; 2,2’-bpy=2,2’-bipyridine) was prepared by solvent method and characterized with X-ray single-crystal diffraction, IR spectroscopy, UV spectroscopy, and fluorescence spectroscopy. The complex crystallized in triclinic crystal system, Pī space group, with a=1.17196(4) nm, b=2.36142(9) nm, c=2.59151(9) nm, α=113.266(2)°, β=101.100(2)°, and γ=94.400(2)°. Two independent dinuclear molecules were contained in the asymmetric unit. The two molecules were similar to each other. Each Eu(Ⅲ) ion was nine-coordinated with seven oxygen atoms from five 2-BrBA ligands and two nitrogen atoms from 2,2’-bpy molecule. The carboxylate groups acted as bidentate-chelating, bidentate-bridging and chelating-bridging coordination modes. The complex adopted a distorted monocapped square-antiprism coordination geometry. Five peaks at 579, 591, 613, 652, and 697 nm appeared in the fluorescence spectrum, corresponding to 5D0→7F0, 5D0→7F1, 5D0→7F2, 5D0→7F3, and 5D0→7F4 transition emissions of the Eu(Ⅲ) ion, respectively.

Hydrothermal Synthesis and Crystal Structure of a New One-dimensional Nickel(Ⅱ) Complex with 2-Pyridinecarboxyic Acid and 4,4′-Bipyridine Ligands

A new metal-organic coordination polymer [Ni[（2-pya）2（4,4′-bipy）]n·6nH2O （2-pya = 2-pyridinecarboxylic acid, 4,4′-bipy = 4,4′-pyridine） 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group I4 1/α with a = b = 22.5642（19）, c = 10.7118（18） A, V = 5453.8（11） A^3, C22H28N4NiO10, Mr= 567.19, Dc = 1.382 g/cm^3, μ（MoKα） = 0.769 mm^-1, F（000） =2368, Z = 8, the final R = 0.0572 and wR = 0.1254 for 1401 observed reflections （I 〉 2σ（I））. It exhibits a one-dimensional chain-like structure by mixed ligands of 2-pyridinedicarboxylic acid and 4,4′-pyridine.

Synthesis and Crystal Structure of a Cu(Ⅱ) Complex with Reduced Schiff-base N-(2-Hydroxybenzyl)-D,L-alanine and 4,4'-Bipyridine

A new complex [Cu2（sala）2（H20）2（4,4＇-bipy）]＇H20 （sala = N-（2-hydroxybenzyl）- D,L-alaninate, 4,4＇-bipy = 4,4＇-bipyridine） has been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. The complex crystallizes in monoclinic system, space group C2/c with a = 42.44（3）, b = 10.416（8）, c = 15.487（13） ./k, fl = 97.455（14）°, C30H36Cu2N4O9, Mr = 723.71, V = 6789（9） A3, Dc = 1.416 g/cm3, Z = 8, F（000） = 2992, μ（MoKa） = 1.308 mm-1, R = 0.0493 and wR = 0.1004 for 4878 observed reflections （I 〉 2σ（I））. Structural analysis shows that each copper（II） atom displays a distorted square-based pyramidal coordination geometry with two oxygen atoms and one nitrogen atom from one N-（2-hydroxybenzyl）-D,L-alaninate, one nitrogen atom from 4,4＇-bipyridine ligand and one water molecule. 4,4＇-Bipyridine ligand bridges two Cu（II） ions to form a dinuclear compound. The molecular structure is extended into a one-dimensional wavy chain through hydrogen bonds. These 1D chains are further expanded into 2D networks through hydrogen bonds.

Synthesis, Crystal Structure and Catalytic Activity of a Bimetallic Rhodium Complex with 1,5-Cyclooctadiene and 2,2'-Bipyridine

A new complex [Rh（COD）（2,2＇-bipy）]·[Rh（COD）Cl2]（COD = 1,5-cyclooctadiene, 2,2＇-bipy = 2,2＇-bipyridine） has been synthesized and characterized by elemental analyses, NMR and single-crystal X-ray diffraction. The complex crystallizes in triclinic system, space group P1 with a = 7.4782（14）, b = 10.1400（11）, c = 16.6982（14） , α = 103.494（11）, β = 91.996（13）, γ = 103.829（12）o, C26H32Cl2N2Rh2, Mr = 649.26, V = 1190.0（3）3, Dc = 1.812 g/cm3, Z = 2, F（000） = 652, μ（Mo Kα） = 1.629 mm-1, R = 0.0286 and w R = 0.0463 for 3718 observed reflections（I 2σ（I））. The complex was linked to form 1D chains by hydrogen bonding interaction（C–H···Cl）, and further to construct a 2D layer structure by π···π stacking interactions between the pyridine rings of 2,2＇-bipy ligands. The hydroformylation catalyzed by the title complex was also studied.

Hydrothermal Synthesis and Crystal Structure of a New One-dimensional Cobalt(Ⅱ) Complex with 2-Pyridinecarboxyic Acid and 4,4′-Bipyridine Ligands

A new metal-organic coordination polymer [Co（2-pya）2（4,4＇-bipy）]2n-[（4,4＇- bipy）0.5· H2O]2n （2-pya = 2-pyridinecarboxylic acid, 4,4＇-bipy = 4,4＇-bipyridine） 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group I41/a with a = b = 22.719（2）, c = 10.710（2）/k, V = 5527.8（14） A3, C54H46N10Co2O10, Mr= 1112.87, Dc = 1.337 g/cm3,μ（MoKa） = 0.665 mm-1, F（000） = 2296, Z = 4, the final R = 0.0633 and wR = 0.1096 for 1261 observed reflections （I 〉 2σ（I））. It exhibits a one-dimensional chain-like structure constructed by mixed ligands of 2-pyridinedicarboxylic acid and 4,4＇-bipyridine.

OXIDATION OF ALKYLBENZENES CATALYZED BY IRON( Ⅱ,Ⅲ)-1,10-PHENANTHROLINE AND 2, 2'-BIPYRIDINE COMPLEXES

Oxidation of alkybenzenes PhCH_2R(R=H, CH_3, C_2H_5 and n-C_3H_7) under 1 atm. of O_2 or air catalyzed by iron(Ⅱ, Ⅲ)-2,2'-bipyridine and 1,10-phenanthroline complexes, affords the aryl-substituted ketones and alcohols with the conversion of 15.00％～34.58％ containing of 97.60％～99.80％ ketones and alcohols. The turnover numbers of these catalysts are over 3500 mol-cat. ^(-1)for 3.5 h.

Synthesis,Crystal Structure and Bioactivity of a Pd(Ⅱ) Complex with Demethylcantharate and 2,2′-Bipyridine

A novel crystal with the molecular formula [Pd（DCA）（bipy）]2 [Pd（bipy）Cl2 ]·6.75H2O was formed by PdCl2 with disodium demethylcantharate （Na2 （DCA）,DCA2= 7-oxa-bicyclo[2.2.1]heptane-2,3-bicarboxylate） and 2,2-bipyidine （bipy） through the hydrothermal method.The complex was characterized by elemental analysis and infrared spectroscopy.The structure of the complex was determined by single-crystal X-ray diffraction,which is of triclinic system,space group P1 with a=13.6818（7）,b=14.8426（8）,c=15.0043（8）,α=97.319（3）,β=92.521（3）,γ=105.776（2）°,V=2898.4（3） 3,Dc=1.545 g·cm-3,Z=1,F（000）=1420,S=0.852,the final R=0.0525 and wR=0.1777 for 13634 observer reflections （I〉2σ（I））.The binding reaction of the complex with ct-DNA and bovine serum albumin （BSA） was studied by fluorescence spectroscopy.The results indicated that the complex binds to ct-DNA via the partial intercalation.The binding constant K A of the complex interaction with BSA was 3.98×10 5 L·mol-1 and one binding site would be formed.The antiproliferative activity of the complex against human hepatoma cells （SMMC7721） in vitro is much higher than that of Na 2 （DCA）.

Synthesis and Crystal Structure of a New Mononuclear Cu(Ⅱ) Complex with 4,4'-Dimethyl-2,2'-bipyridine

A new mononuclear copper (II) complex, [Cu(dbpy)2Cl]OH0.5CH3OH2H2O (dbpy = 4,4?dimethyl-2,2?bipyridine) (C24.50H31ClCuN4O3.50, Mr = 536.52) has been synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in monoclinic, space group P2/c with a = 13.383(6), b = 7.653(3), c = 14.164(6) ? b = 105.395(8), V = 1398.7(10) 3, Z = 2, Dc = 1.274 g/cm3, m = 0.908 mm-1, F(000) = 560 and R = 0.0773 for 1467 observed reflections with I>2s(I). Each copper(II) ion is coordinated by two dbpy and one Cl- ion and the coordination geometry can be described as a distorted trigonal bipyramidal arrange- ment.

Investigation of Intermolecular C-H···Halogen Hydrogen Bonded Supramolecular Assemblies in Three Copper(Ⅰ) Complexes Formed by 3,3'-Dimethoxy-6,6'-dimethyl-2,2'-bipyridine Ligand

Three new crystalline compounds 1-3 were successfully obtained by the reactions of 3,3＇-dimethoxy-6,6＇-dimethyl-2,2＇-bipyridine ligand（dmbp） with the corresponding Cu（Ⅰ） salts.Crystal data for 1：orthorhombic Pbca,a = 18.5858（12）,b = 8.1821（5）,c = 20.6066（13） ,V = 3133.7（3） 3,Z = 8,Dc = 1.843 g/cm3,F（000） = 1696,μ = 3.366 mm-1,the final R = 0.0223 and wR = 0.0542.Crystal data for 2：Orthorhombic Pbca,a = 18.7883（16）,b = 8.3249（7）,c = 19.0294（17） ,V = 2976.4（4） 3,Z = 8,Dc = 1.731 g/cm3,F（000） = 1552,μ = 4.154 mm-1,the final R = 0.0279 and wR = 0.0680.Crystal data for 3：monoclinic P21/c,a = 13.812（10）,b = 9.910（7）,c = 23.444（17） ,β = 104.3350（10）°,V = 3090（4） 3,Z = 4,Dc = 1.476 g/cm3,F（000） = 1408,μ = 1.588 mm-1,the final R = 0.0479 and wR = 0.1081.The results of X-ray crystallographic analysis revealed that C14H16ICuN2O2（1） and C14H16BrCuN2O2（2） are isostructural compounds with the dimers connected by C-H···halogen hydrogen bonds to generate a three-dimensional（3D） supramolecular network in 1 and a two-dimensional（2D） sheet structure in 2,respectively,while the mononuclear complex C28H32Cl2Cu2N4O4（3） is ionic.In 3,the [Cu（dmbp）2]＋ cations and [ClCuCl]-anions are connected by C-H···Cl hydrogen bonds to form a one-dimensional（1D） chain along the a axis.Therefore,in the three complexes,the C-H···halogen hydrogen bonds dominate their crystal structures.Additionally,The UV luminescent properties of complexes 1-3 were investigated.

Synthesis and Characterization of New Palladium（ll） Complexes Containing 4,5-dimethyl-2,2＇-bipyridine： X-ray Crystal Structure of Bis（4-methyl pyrdine）-4,5- dimethyl-2,2＇-bipyridine palladium （11） Perchlorate

New heteroleptic and homoleptic complexes of the type[Pd（4,5-dmbipy）C12], [Pd（4,5-dmbipy）L2], and [Pd（4,5-dimebipy）2]2＋ （L = Pyridine or 4-methylpyridine（4-picoline）, bipy = 2,2＇-bipyridine, and 4,5-dimebipy = 4,5-dimethyl-2,2＇-bipyridine） were synthesized and characterized by IH NMR and elemental analysis. The crystal structure of bis（4-methylpyridine）-4,5- dimethyl-2,2＇-bipyridinepalladium（II）perchlorate [Pd（4,5-dmbipy）（4-pic）2]（CIO4）2 was also determined by single crystal X-ray diffraction. This complex crystallized in the triclinic crystal system and space group PI with a = 9.562 （2）, b = 11.326 （4）, c = 15.0120 （10） A°; α = 70.940°, β= 77.60 （2）, γ= 67.86 （2） and z = 4. The Pd （II） in square planar environment showed a small distortion towards tetrahedral through one coordinated bipyridine ring twisting with respect to the other.

Two New Organic Supramolecular Complexes Based on 2,3,6,7-Tetrahydroxyl-9,10-dimethyl-9,10-dihydro-9,10-ethanoanthracene and 4,4′-Bipyridine or 4,4′-Bipyridinylethane

Two new organic supramolecular cocrystal complexes C18H18O4·C10H8N2（I） and C18H18O4·C12H10N2（II）（C18H18O4 = 2,3,6,7-tetrahydroxyl-9,10-dimethyl-9,10-dihydro-9,10-ethanoanthracene（LH4）, C10H8N2 = 4,4＇-bipyridine（bpy） and C12H10N2 = 4,4＇-bipyridinylethane（bpe）） have been obtained by mixing LH4 with corresponding bpy or bpe ligand. The two complexes have been determined by X-ray crystal structure analysis, elemental analysis and IR analysis. Compound I crystallizes in the orthorhombic Pnma with a = 9.7078（4）, b = 22.4974（10）, c = 20.6272（9） V = 4505.0（3）3, Mr = 454.51, Dc. = 1.340 g·cm^-3, μ = 0.09 mm-1, F（000） = 1920, Z = 8, R = 0.0503 and wR = 0.1360. Compound II crystallizes in monoclinic C2/c with a = 29.944（6）, b = 9.820（2）, c = 22.643（5） , V = 5048.4（18）3, Mr = 480.54, Dc. = 1.265 g cm^–3, μ = 0.084 mm^–1, F（000） = 2032, Z = 8, R = 0.0548 and wR = 0.1600. X-ray single-crystal structure analysis shows that two-dimensional（2D） layer supramolecular structures are formed through hydrogen bonds and π-π interactions in the two complexes. IR analysis also indicates that there are only associated hydroxyl groups in the two complexes.

Two New Cu(Ⅱ) Coordination Polymers Based on 2,5-Furandicarboxylic Acid and 2,2'-bipyridine:Synthesis and Crystal Structure

Two new Cu（II） coordination polymers, [Cu（FDA）（BPY）（H20）]n （1） and {[Cu（FDA）（BPY）（H2O）].2H2O}n （2） （H2FDA = 2,5-furandicarboxylic acid, BPY = 2,2＇-bipyridine）, have been synthesized and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. Compound 1 crystallizes in monoclinic, space group P21/c, with a = 7.5915（15）, b = 8.4050（17）, c = 24.204（6） A, β = 99.05（3）°, V= 1525.1（6） A3, Dc = 1.706 g/crn3, C16HI2CuN206, Mr = 391.82, F（000） = 796, μ（MoKa） = 1.470 mm-l, Z = 4, R = 0.0633 and wR = 0.1059 for 2389 observed reflections （1 〉 2a（I））, R = 0.0738, and wR = 0.1098 for all data. Complex 2 belongs to triclinic space group PI with a = 8.8660（18）, b = 8.9112（18）, c = 12.525（3） A, a = 88.41（3）, β = 69.38（3）, γ = 66.95（3）°, V = 845.2（3） A3, Dc = 1.681 g/cm3, CI6HI6CuN2Os, Mr. = 427.85, F（000） = 438, μ（MoKα） = 1.342 mm-1, Z = 2, R = 0.0290 and wR = 0.0690 for 2767 observed reflections （I 〉 2σ（I））, R = 0.0329 and wR = 0.0706 for all data. Complexes 1 and 2 are both coordination polymers with one-dimensional chain structures bridged by the protonated FDA ligands, which are assembled into three-dimensional supramolecular structures through hydrogen bonding interactions and π-π packing interactions between the chains.

Metal-directed Assembly of Two Distinct Coordination Polymers with 2,5-Furandicarboxylic Acid and 4,4'-Bipyridine

By using solvothermal method, two new metal coordination polymers based on 2,5-furandicarboxylic acid（H2FDA） ligand and 4,4＇-bipyridine（bipy）, [Cu（FDA）（4,4＇-bipy）（DMF）]n·solvent（1） and {[Zn（4,4＇-bipy）（FDA）（DMF）]·DMF}n（2）, were produced and characterized by single-crystal X-ray diffraction analyses, elemental analyses, IR and powder X-ray diffraction. Compound 1 crystallizes in monoclinic space group P21/c with a = 11.104（2）, b = 10.396（2）, c = 18.772（4） , β = 96.20（3）o, V = 2154.2（7） 3, Dc = 1.378 g/cm^3, C19H17 Cu N3O6, Mr = 446.90, F（000） = 916, μ（Mo Kα） = 1.05 mm^-1, Z = 4, R = 0.0691 and wR = 0.1341 for 3537 observed reflections（I 2σ（I））, and R = 0.1062 and w R = 0.1482 for all data. Compound 2 crystallizes in monoclinic space group C2/c with a = 29.779（6）, b = 9.6417（19）, c = 17.292（3）, β = 105.69（3）°, V = 4779.9（16） 3, Dc = 1.445 g/cm^3, C22H22N4O7 Zn, Mr = 519.81, F（000） = 2144, μ（Mo Kα）= 1.08 mm^-1, Z = 8, R = 0.0641 and w R = 0.1007 for 2985 observed reflections（I 2σ（I））, and R = 0.1028 and w R = 0.1112 for all data. Different coordination geometry of metal ions, square pyramid of Cu2＋ and trigonal bipyramid of Zn2＋, bring about different orientations of FDA2- ligands as well as 4,4＇-bipyridine ligands, and furthermore distinct assembly structures for 1 and 2. The thermal stabilities of 1 and 2 are also investigated.

pH Dependent Supramolecules Based on Co-crystallization of Pyrazine-2,3,5,6-tetracarboxylic Acid with 4,4＇-Bipyridine through Intermolecular Hydrogen Bonds

Co-crystallization of pztcH_4 with 4,4＇-bipyridine（4,4＇-bipy） in pH = 3-4 and 1-2 gave two new binary molecular adducts： [（4,4＇-bipy H2）（pztc H2）]（1） and [（4,4＇-bipy H2）（pztcH3）（Cl）]·4H2O（2）, respectively. Compounds 1 and 2 have been characterized by IR, elemental analysis, NMR and X-ray single-crystal diffraction. Compound 1 crystallizes in triclinic, space group P1 with a = 5.7752（12）, b = 7.9126（16）, c = 9.4492（19） ？, α = 97.49（3）, β = 107.71（3）, γ = 94.52（3）o, V = 404.62（14） A^3, Z = 1, μ = 0.137 mm^1, Dc = 1.692 Mg/m^3, C18H12N4O8, Mr = 412.32, F（000） = 212, S = 1.025, R = 0.0360 and wR = 0.0973. Compound 2 crystallizes in monoclinic, space group C2/c with a = 17.093（3）, b = 7.7665（16）, c = 18.414（4） A, β = 113.36（3）o, V = 2244.1（8） A^3, Z = 4, μ = 0.244 mm^-1, Dc = 1.542 Mg/m^3, C18H21ClN4O12, Mr = 520.84, F（000） = 1080, S = 1.021, R = 0.0343 and wR = 0.0978. In compound 1, pztc H22- anions self-formed 2-D sheets by strong Oacid-H···Oacidhydrogen bonds, which are further extended to form a 3-D supramolecular network bridged with 4,4？-bipy via N-H···Oacid interactions. In compound 2, besides the 1-D chain constructed by pztc H3-itself through strong H-bond Oacid-H···Oacid, the other chain is constructed with 4,4？-bipy H22＋, Cl-anion and water molecules by moderate H-bonds and Ow-H···Cl and N-H···Ow. The two chains are linked with μ3-connected water molecules resulting from the combination of strong synthon-assisted H-bonding Oacid-H···Ow to afford an interlaced 3-D network.

Effects of axylitol-casein complex on insulin resistance and gut microbiota composition in high-fat-diet+streptozotocin-induced type 2 diabetes mellitus mice

This study investigated the effects of a xylitol-casein non-covalent complex(XC)on parameters related to type 2 diabetes mellitus(T2DM),in addition to related changes in gut microbiome composition and functions.High-fat-diet(HFD)+streptozotocin(STZ)-induced T2DM mice were treated with xylitol(XY),casein(CN),and XC,after which fecal samples were collected for gut microbiota composition and diversity analyses based on 16S rRNA high-throughput sequencing and multivariate statistics.XC decreased body weight and improved glucose tolerance,insulin sensitivity,pancreas impairment,blood lipid levels,and liver function in T2DM mice compared to XY-and CN-treated mice.Furthermore,XC modulated theα-diversity,β-diversity and gut microbiota composition.Based on Spearman’s correlation analysis,the relative abundances of Alistipes,Bacteroides,and Faecalibaculum were positively correlated and those of Akkermansia,Lactobacillus,Bifidobacterium,and Turicibacter were negatively correlated with the phenotypes related to the improvement of T2DM.In conclusion,we found that XC alleviated insulin resistance by restoring the gut microbiota of T2DM mice.Our results provide strong evidence for the beneficial effects of XC on T2DM and motivation for further investigation in animal models and,eventually,human trials.

Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration

Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain lateral comparison profile and seismic reflection structures in the 2D seismic section, which can provide references for future worldwide exploration. Microbial mounds with larger buildups and thicker vertical reservoirs are typically targeted on the windward margin, while small-sized microbial mounds and flats with better lateral connections are typically focused on the leeward margin.

The Impact of Storyline Complexity on L2 Learners’Written Performance

Task-based Language Teaching(TBLT)research has provided ample evidence that cognitive complexity is an important aspect of task design that influences learner’s performance in terms of fluency,accuracy,and syntactic complexity.Despite the substantial number of empirical investigations into task complexity in journal articles,storyline complexity,one of the features of it,is scarcely investigated.Previous research mainly focused on the impact of storyline complexity on learners’oral performance,but the impact on learners’written performance is less investigated.Thus,this study aims at investigating the effects of narrative complexity of storyline on senior high school students’written performance,as displayed by its complexity,fluency,and accuracy.The present study has important pedagogical implications.That is,task design and assessment should make a distinction between different types of narrative tasks.For example,the task with single or dual storyline.Results on task complexity may contribute to informing the pedagogical choices made by teachers when prioritizing work with a specific linguistic dimension.

Octa-membered Water Ring Chain Based on Sulfonic Group in Ni(II) Complex with 2-[(E)-(2-Oxidophenyl)methyleneamino] Ethanesulfonato and 2,2′-Bipyridinyl

The title compound, [Ni（tssb）（2,2-bipy）2].5（H2O） 1 （tssbH2 =2-[（E）-（2-oxido- phenyl）methyleneamino]ethanesulfonato, 2,2-bipy = 2,2＇-bipyridinyl）, belongs to orthorhombic, space group Pbcn with a = 20.3983（18）, b = 17.6929（15）, c = 17.0897（15） nm, V= 6167.8（9） nm^3, Mr= 688.38, Z = 8, De = 1.481 g.cm^-3, F（000） = 2880,μ = 0.758 mm-1 and S =1.099. Each NiIr atom is six-coordinated by one N and one O atoms from one tssb^2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-mem- bered water ring which presents a 1D chain by sulfonic group.