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-f...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.展开更多
Reconstituting membrane proteins in liposomes and determining their structure is a common method for determining membrane protein structures using single-particle cryo-electron microscopy(cryo-EM).However,the strong s...Reconstituting membrane proteins in liposomes and determining their structure is a common method for determining membrane protein structures using single-particle cryo-electron microscopy(cryo-EM).However,the strong signal of liposomes under cryo-EM imaging conditions often interferes with the structural determination of the embedded membrane proteins.Here,we propose a liposome signal subtraction method based on single-particle two-dimensional(2D)classification average images,aimed at enhancing the reconstruction resolution of membrane proteins.We analyzed the signal distribution characteristics of liposomes and proteins within the 2D classification average images of protein–liposome complexes in the frequency domain.Based on this analysis,we designed a method to subtract the liposome signals from the original particle images.After the subtraction,the accuracy of single-particle three-dimensional(3D)alignment was improved,enhancing the resolution of the final 3D reconstruction.We demonstrated this method using a PIEZO1-proteoliposome dataset by improving the resolution of the PIEZO1 protein.展开更多
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 p...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.展开更多
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 ...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.展开更多
A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP ...A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP polymer was characterized by NMR, IR, and UV-visible spectroscopy. The reaction of PVA-DNP with sodium methoxide was followed by NMR and UV-visible spectroscopy. Evidence of polymer bound spirocyclic SIGMA complex, C-1 and C-3 polymer bound DNP-methoxy SIGMA complexes and the formation and C-1 methoxy complex of 2,4-dinitroanisole was observed.展开更多
Eight complexes of rare earth with 2 mercaptobenthiazole, RELCl 2·RE(OH) 3· x H 2O (L=2 mercaptobenthiazole, RE= La~Gd, Y, except for Pm, x =0, 2~4), were synthesized in unhydrous ethanol and char...Eight complexes of rare earth with 2 mercaptobenthiazole, RELCl 2·RE(OH) 3· x H 2O (L=2 mercaptobenthiazole, RE= La~Gd, Y, except for Pm, x =0, 2~4), were synthesized in unhydrous ethanol and characterized by elemental analyses, IR spectra and thermal analyses. The results show that the ligand is coordinated to the RE ion through both the exocyclic sulfur and the thiazole nitrogen. The vulcanizing properties of the La complex as accelerator were studied in the traditional tire rubber, which indicate that the cross linked rubber accelerated by the rare earth complex has good physical and dynamic mechanical properties by comparison.展开更多
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....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.展开更多
Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTP...Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTPY)(H2O)]n·2nH2O(5), and [Co(HBTC)(PYTPY)(H2O)2](6),(H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4'-(4-pyridyl)-2,2':6',2''-terpyridine, DMF = N,N?-dimethylformamide), have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional(3D) supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties.展开更多
Metal (Me=Fe(III), Mo(VI), Mn(II), Co(II), Ni(II), Zn(II) and Cu(II)) 2-hydroxy-1-naphthaldehyde thiosemicarbazone complexes (MeHNT) were synthesized and used as mimic-enzyme catalysts to mimic the active group of hor...Metal (Me=Fe(III), Mo(VI), Mn(II), Co(II), Ni(II), Zn(II) and Cu(II)) 2-hydroxy-1-naphthaldehyde thiosemicarbazone complexes (MeHNT) were synthesized and used as mimic-enzyme catalysts to mimic the active group of horseradish peroxidase (HRP). The results showed that Fe-HNT, Mo-HNT are effective catalysts, which have similar catalytic activity as HRP. The sequence of catalytic activities of tested biomimic peroxidas is Mo-HNT > Fe-HNT > Zn-HNT > Ni-HNT > Mn-HNT. Among them, Fe-HNT is used as a mimic-enzyme catalyst in determination of ascorbic acid and glucose by coupling the catalytic reaction of glucose oxidase.展开更多
Two new metal-organic complexes [Cd2(1,4-BDC)(4-pytyp)(H2O)4]·(1,4-BDC)(1) and [Cu2(1,4-BDC)(4-pytyp)2(H2O)2]·(1,4-BDC)·8H2O(2)(4-pytyp = 4'-(4''-pyridyl)-2,2':6',2''-terp...Two new metal-organic complexes [Cd2(1,4-BDC)(4-pytyp)(H2O)4]·(1,4-BDC)(1) and [Cu2(1,4-BDC)(4-pytyp)2(H2O)2]·(1,4-BDC)·8H2O(2)(4-pytyp = 4'-(4''-pyridyl)-2,2':6',2''-terpyridine, 1,4-H2 BDC = 1,4-benzenedicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The scrutiny of single-crystal structure reveals that complex 1 forms to a 3D supramolecular network linked by π-π stacking interactions and hydrogen bonds. X-ray diffraction analysis reveals that complex 2 exhibits a 3D supramolecular network linked through complicated hydrogen bonds. The thermogravimetric analysis and photoluminescent properties of 1 and 2 are discussed in detail.展开更多
Two novel supramolecular complexes,[M4L12]·(HPO4)·(PO4)2(L = 2,2'-dibenzi-midazole,M = Co and Ni) were synthesized by the hydrothermal method and characterized by elemental analysis,IR,UV,and TG-TGA,a...Two novel supramolecular complexes,[M4L12]·(HPO4)·(PO4)2(L = 2,2'-dibenzi-midazole,M = Co and Ni) were synthesized by the hydrothermal method and characterized by elemental analysis,IR,UV,and TG-TGA,and the crystal structures were determined by single-crystal X-ray diffraction.The results showed that both of them belong to the cubic system and space group I 4 3d.Crystal parameters of C168H121Co4N48O12P3(1):a = b = c = 2.5104(6) nm,V = 15.820(7) nm3,Mr = 3332.75,Z = 4,Dc = 1.399 Mg/m3,μ = 0.521 mm-1,F(000) = 6852,S = 1.011,the final R = 0.0248 and wR = 0.0663 for 2120 observed reflections(I 2σ(I)) and R = 0.0315 and wR = 0.0706 for all data.Crystal parameters of C168H121Ni4N48O12P3(2):a = b = c = 2.4977(5) nm,V = 15.581(5) nm3,Mr = 3331.87,Z = 4,Dc = 1.420 Mg/m3,μ = 0.587 mm-1,F(000) = 6868,S = 1.074,the final R = 0.0443 and wR = 0.1364 for 1774 observer reflections(I 2σ(I)) and R = 0.0647 and wR = 0.1492 for all data.Each of them consisted of four M(II) cations,twelve 2,2'-dibenzimidazole ligands,one monohydrogen phosphate anion and two phosphate anions in the single cell.The central M(II) cation,coordinated with six alkaline nitrogen atoms from three 2,2'-dibenzimidazole ligands,displayed the expected distorted-octahedral geometry.The 3D supramolecular system was formed by the hydrogen bond N-H...O and π-π stacking interaction between neighboring single cells.Complex 1 showed two irreversible single-electron reduction processes of the central metal ion at-0.06 and-0.42 V in DMF solution.展开更多
Two new metal-organic complexes,{[Co2(bptc)(DPPZ)2(H2O)2]·H2O}n 1 and {[Co2(ccm)2(DPPZ)2]·2H2O}n 2,were obtained by the hydrothermal reactions of Co(NO3)2·6H2O with chelating ligand dipyrido...Two new metal-organic complexes,{[Co2(bptc)(DPPZ)2(H2O)2]·H2O}n 1 and {[Co2(ccm)2(DPPZ)2]·2H2O}n 2,were obtained by the hydrothermal reactions of Co(NO3)2·6H2O with chelating ligand dipyrido[3,2-a:2',3'-c]phenazine(DPPZ) and the corresponding carboxylic acid,namely,3,3',4,4'-benzophenonetetracarboxylic acid(H4bptc) or 2-carboxycinnamic acid(H2ccm),respectively.The complexes were structurally characterized by single-crystal X-ray diffraction,elemental analyses,IR spectra,and thermal gravimetry.1 presents unique chiral chain structures,which are further consolidated into three-dimensional supramolecular frameworks via noncovalent bonds,such as hydrogen bonding and π-π interactions.2 features infinite double-chain structures,which are connected by strong π-π interactions to result in three-dimensional supramolecular architectures.展开更多
A series of new nickel(Ⅱ)complexes with 2-aminomethylpyridine ligands,(2-PyCH_2NHAr)_2NiBr_2(Ar=2,6- dimethylphenyl 2a;2,6-diisopropylphenyl 2b,2,6-difluorophenyl 2c),have been synthesized and used as catalyst precur...A series of new nickel(Ⅱ)complexes with 2-aminomethylpyridine ligands,(2-PyCH_2NHAr)_2NiBr_2(Ar=2,6- dimethylphenyl 2a;2,6-diisopropylphenyl 2b,2,6-difluorophenyl 2c),have been synthesized and used as catalyst precursors for ethylene polymerization in the presence of methylaluminoxane(MAO).The catalysts containing ortho-alkyl-substituents afford high molecular weight branched polyethylenes as well as a certain amount of oligomers.Enhancing the steric bulk of the alkyl substituent of the catalyst resulted in...展开更多
Two new three-dimensional supramolecular complexes, namely, [Cd(cba)2(bib)]n(1) and [Zn(cba)2(bib)]2 n(2)(Hcba = 2-chlorinebenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane)were hydrothermally designed and synthesized...Two new three-dimensional supramolecular complexes, namely, [Cd(cba)2(bib)]n(1) and [Zn(cba)2(bib)]2 n(2)(Hcba = 2-chlorinebenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane)were hydrothermally designed and synthesized. Their structures were determined by elemental analyses, IR spectroscopy, TG, fluorescence spectroscopy, single-crystal and powder X-ray diffraction. Complex 1 exhibits a one-dimensional zigzag chain and complex 2 shows a zero-dimensional structure, which were further extended into three-dimensional supramolecular structures through hydrogen bonds and π-π stacking interactions.展开更多
基金supported by the “Thirteenth Five Year” National Science and Technology Plan Project of China (2018YFC1603703,2018YFC1604302)National Natural Science Foundation of China (2013BAD18B03)+1 种基金Shenyang Technological Innovation Project (Y170-028)LiaoNing Revitalization Talents Project (XLYC1902083)
文摘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.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.32241023 and 92254306)the Fund from the Tsinghua–Peking Joint Center for Life SciencesBeijing Frontier Research Center for Biological Structure。
文摘Reconstituting membrane proteins in liposomes and determining their structure is a common method for determining membrane protein structures using single-particle cryo-electron microscopy(cryo-EM).However,the strong signal of liposomes under cryo-EM imaging conditions often interferes with the structural determination of the embedded membrane proteins.Here,we propose a liposome signal subtraction method based on single-particle two-dimensional(2D)classification average images,aimed at enhancing the reconstruction resolution of membrane proteins.We analyzed the signal distribution characteristics of liposomes and proteins within the 2D classification average images of protein–liposome complexes in the frequency domain.Based on this analysis,we designed a method to subtract the liposome signals from the original particle images.After the subtraction,the accuracy of single-particle three-dimensional(3D)alignment was improved,enhancing the resolution of the final 3D reconstruction.We demonstrated this method using a PIEZO1-proteoliposome dataset by improving the resolution of the PIEZO1 protein.
基金jointly funded by projects supported by the National Natural Science Foundation of China(Grant No.41872150)the Joint Funds of the National Natural Science Foundation of China(Grant No.U19B6003)Major Scientific and Technological Projects of CNPC during the 13th five-year plan(No.2019A-02-10)。
文摘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.
文摘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.
文摘A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP polymer was characterized by NMR, IR, and UV-visible spectroscopy. The reaction of PVA-DNP with sodium methoxide was followed by NMR and UV-visible spectroscopy. Evidence of polymer bound spirocyclic SIGMA complex, C-1 and C-3 polymer bound DNP-methoxy SIGMA complexes and the formation and C-1 methoxy complex of 2,4-dinitroanisole was observed.
文摘Eight complexes of rare earth with 2 mercaptobenthiazole, RELCl 2·RE(OH) 3· x H 2O (L=2 mercaptobenthiazole, RE= La~Gd, Y, except for Pm, x =0, 2~4), were synthesized in unhydrous ethanol and characterized by elemental analyses, IR spectra and thermal analyses. The results show that the ligand is coordinated to the RE ion through both the exocyclic sulfur and the thiazole nitrogen. The vulcanizing properties of the La complex as accelerator were studied in the traditional tire rubber, which indicate that the cross linked rubber accelerated by the rare earth complex has good physical and dynamic mechanical properties by comparison.
文摘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.
基金Supported by the National Natural Science Foundation of China(No.21576112)Natural Science Foundation of Jilin Province(20150623024TC-19,20170520147JH)the Science and Technology Development Plan of Siping City(2015049)
文摘Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTPY)(H2O)]n·2nH2O(5), and [Co(HBTC)(PYTPY)(H2O)2](6),(H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4'-(4-pyridyl)-2,2':6',2''-terpyridine, DMF = N,N?-dimethylformamide), have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional(3D) supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties.
文摘Metal (Me=Fe(III), Mo(VI), Mn(II), Co(II), Ni(II), Zn(II) and Cu(II)) 2-hydroxy-1-naphthaldehyde thiosemicarbazone complexes (MeHNT) were synthesized and used as mimic-enzyme catalysts to mimic the active group of horseradish peroxidase (HRP). The results showed that Fe-HNT, Mo-HNT are effective catalysts, which have similar catalytic activity as HRP. The sequence of catalytic activities of tested biomimic peroxidas is Mo-HNT > Fe-HNT > Zn-HNT > Ni-HNT > Mn-HNT. Among them, Fe-HNT is used as a mimic-enzyme catalyst in determination of ascorbic acid and glucose by coupling the catalytic reaction of glucose oxidase.
基金Supported by the Program for New Century Excellent Talents in University(NCET-10-0176)the Natural Science Foundation of Jilin Province(No.20130521019JH)the fund of Jilin Provincial Education Department of China(No.2014154)
文摘Two new metal-organic complexes [Cd2(1,4-BDC)(4-pytyp)(H2O)4]·(1,4-BDC)(1) and [Cu2(1,4-BDC)(4-pytyp)2(H2O)2]·(1,4-BDC)·8H2O(2)(4-pytyp = 4'-(4''-pyridyl)-2,2':6',2''-terpyridine, 1,4-H2 BDC = 1,4-benzenedicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The scrutiny of single-crystal structure reveals that complex 1 forms to a 3D supramolecular network linked by π-π stacking interactions and hydrogen bonds. X-ray diffraction analysis reveals that complex 2 exhibits a 3D supramolecular network linked through complicated hydrogen bonds. The thermogravimetric analysis and photoluminescent properties of 1 and 2 are discussed in detail.
基金Project Supported by the Science & Technology Innovation Foundation of Henan Province (No. 092102310309)
文摘Two novel supramolecular complexes,[M4L12]·(HPO4)·(PO4)2(L = 2,2'-dibenzi-midazole,M = Co and Ni) were synthesized by the hydrothermal method and characterized by elemental analysis,IR,UV,and TG-TGA,and the crystal structures were determined by single-crystal X-ray diffraction.The results showed that both of them belong to the cubic system and space group I 4 3d.Crystal parameters of C168H121Co4N48O12P3(1):a = b = c = 2.5104(6) nm,V = 15.820(7) nm3,Mr = 3332.75,Z = 4,Dc = 1.399 Mg/m3,μ = 0.521 mm-1,F(000) = 6852,S = 1.011,the final R = 0.0248 and wR = 0.0663 for 2120 observed reflections(I 2σ(I)) and R = 0.0315 and wR = 0.0706 for all data.Crystal parameters of C168H121Ni4N48O12P3(2):a = b = c = 2.4977(5) nm,V = 15.581(5) nm3,Mr = 3331.87,Z = 4,Dc = 1.420 Mg/m3,μ = 0.587 mm-1,F(000) = 6868,S = 1.074,the final R = 0.0443 and wR = 0.1364 for 1774 observer reflections(I 2σ(I)) and R = 0.0647 and wR = 0.1492 for all data.Each of them consisted of four M(II) cations,twelve 2,2'-dibenzimidazole ligands,one monohydrogen phosphate anion and two phosphate anions in the single cell.The central M(II) cation,coordinated with six alkaline nitrogen atoms from three 2,2'-dibenzimidazole ligands,displayed the expected distorted-octahedral geometry.The 3D supramolecular system was formed by the hydrogen bond N-H...O and π-π stacking interaction between neighboring single cells.Complex 1 showed two irreversible single-electron reduction processes of the central metal ion at-0.06 and-0.42 V in DMF solution.
基金Supported by the National Natural Science Foundation of China (No. 60978059)Program for New Century Excellent Talents in University (NCET-10-0176)the Natural Science Foundation of Jilin Province (No. 20090527)
文摘Two new metal-organic complexes,{[Co2(bptc)(DPPZ)2(H2O)2]·H2O}n 1 and {[Co2(ccm)2(DPPZ)2]·2H2O}n 2,were obtained by the hydrothermal reactions of Co(NO3)2·6H2O with chelating ligand dipyrido[3,2-a:2',3'-c]phenazine(DPPZ) and the corresponding carboxylic acid,namely,3,3',4,4'-benzophenonetetracarboxylic acid(H4bptc) or 2-carboxycinnamic acid(H2ccm),respectively.The complexes were structurally characterized by single-crystal X-ray diffraction,elemental analyses,IR spectra,and thermal gravimetry.1 presents unique chiral chain structures,which are further consolidated into three-dimensional supramolecular frameworks via noncovalent bonds,such as hydrogen bonding and π-π interactions.2 features infinite double-chain structures,which are connected by strong π-π interactions to result in three-dimensional supramolecular architectures.
基金the National Natural Science Foundation of China(Nos.20674097,20734004)the Ministry of Education of China(Foundation for Ph.D.Training).
文摘A series of new nickel(Ⅱ)complexes with 2-aminomethylpyridine ligands,(2-PyCH_2NHAr)_2NiBr_2(Ar=2,6- dimethylphenyl 2a;2,6-diisopropylphenyl 2b,2,6-difluorophenyl 2c),have been synthesized and used as catalyst precursors for ethylene polymerization in the presence of methylaluminoxane(MAO).The catalysts containing ortho-alkyl-substituents afford high molecular weight branched polyethylenes as well as a certain amount of oligomers.Enhancing the steric bulk of the alkyl substituent of the catalyst resulted in...
基金supported by the Science and Technology development plan of Jilin Province(2015052006JH)Science and technology research project of Education Department of Jilin Province(2016219)+1 种基金Center for Science and Technology Innovation on Target recognition and photocatalytic degradation Materials of Jilin Province(20180623042TC)Science and technology development plan of Siping city(2013055)
文摘Two new three-dimensional supramolecular complexes, namely, [Cd(cba)2(bib)]n(1) and [Zn(cba)2(bib)]2 n(2)(Hcba = 2-chlorinebenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane)were hydrothermally designed and synthesized. Their structures were determined by elemental analyses, IR spectroscopy, TG, fluorescence spectroscopy, single-crystal and powder X-ray diffraction. Complex 1 exhibits a one-dimensional zigzag chain and complex 2 shows a zero-dimensional structure, which were further extended into three-dimensional supramolecular structures through hydrogen bonds and π-π stacking interactions.