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Science China Chemistry 2007年第6期50卷 784-789页

作者： wang jingping MA PengTao NIU JingYang Institute of Molecular and Crystal Engineering School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China Institute of Molecular and Crystal Engineering School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China Institute of Molecular and Crystal Engineering School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China

A new organic-inorganic hybrid polyoxometalate based on Dawson-like polyoxotungstate anion [SbW18O60]9, formulated [Co(2,2′-bpy)3]2[Co(2,2′-bpy)2Cl][Co(2,2′-bpy)2]H2[SbW18O60]·4H2O (2,2′-bpy= 2,2′-bipyridine) has been synthesized from Sb2O3, Na2WO4, CoCl2, and 2,2′-bipyridine materials by hydrothermal method, and which was characterized by elemental analyses, IR, XPS, EPR, TG, and X-ray single crystal diffraction. Structure analysis shows that the polyoxoanion self-assembled under hydrothermal conditions consists of a Dawson-like polyoxotungstate cluster anion [SbW18O60]9 en- capsulating a pyramidal {SbO3} group within the {W18} cluster cage. EPR spectra show that the high-spin octahedral CoII and low-spin CoII ions coexist in the title compound. Magnetic properties in- dicate that the compound is antiferromagnetic.

关键词： polyoxometalate, Dawson-like, crystal structure, hydrothermal synthesis

Synthesis,structural characterization and properties of a 3D infinitely extended structural rare earth coordination compound of K_3{[Sm(H_2O)_7]_2Na[α-SiW_(11)O_(39)Sm(H_2O)_4]_2}·14 H_2O

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Science China Chemistry 2005年第4期48卷 343-351页

作者： wang jingping ZHAO Junwei NIU Jingyang Institute of Molecule and Crystal Engineering School of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China Institute of Molecule and Crystal EngineeringSchool of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China Institute of Molecule and Crystal EngineeringSchool of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475001China

A 3D infinitely extended structural rare earth coordination compound with a formula of K3{[Sm(H2O)7]2Na[a-SiW11O39Sm(H2O)4]2}·14H2O has been synthesized by reaction of Sm2O3,HClO4,NaOH with a-K8SiW11O39·nH2O,and characterized by IR,UV spectra,ICP,TG-DTA,cyclic voltammetry,variable-temperature magnetic susceptibility and X-ray single-crystal diffrac-tion.X-ray single-crystal diffraction indicates that the title compound crystallizes in a triclinic lat-tice,Pi space group,with a = 1.2462(3) nm,b = 1.2652(3) nm,c = 1.8420(4) nm,α = 87.45(3)°,β = 79.91(3)°,γ = 82.57(3)°,Z = 1,R1 = 0.0778,wR2 = *** analysis reveals that Sm3+(1) coordination cation has incorporated into the vacant site of [α-SiW11O39]8? entity,forming the [α-SiW11O39Sm(H2O)4]5? *** two adjacent [a-SiW11O39Sm(H2O)4]5? subunits are combined with each other through two Sm(1)-O-W bridges accompanying the formation of dim-mer structural unit [α-SiW11O39Sm(H2O)4]210? of the title *** neighboring dimmer structural units [α-SiW11O39Sm(H2O)4]210? are linked to form the 1D chainlike structure by means of two Sm3+(2) and a Na+(1) coordination *** K+(1) cations connect the 1D packing chains constructing the 2D netlike structure,and adjacent netlike layers are also grafted by K+(2) cations to build the novel 3D infinitely extended *** result of TG-DTA curves manifests that the decomposition temperature of the title polyanionic framework is 554℃.The cyclic volt-ammetry measurements show that the title polyanion has the two-step redox processes in aqueous solution with pH = *** temperature magnetic susceptibility indicates the title compound obeys the Cruie-Weiss Law in the higher temperature range from 110 to 300 K,while in the lower temperature range from 2 to 110 K the comparatively strong antiferromagnetism in-teractions can be observed.

关键词： silicotungstic acid, Keggin structure, crystal structure, polyoxometalates, rare earth metal.

Synthesis,crystal structure and characterization of a 2-D network organic-inorganic hybrid polymer with [α-BW_(12)O_(40) ]^(5) as building blocks

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Science China Chemistry 2006年第5期49卷 437-444页

作者： wang jingping LI Jie NIU Jingyang Institute of Molecular and Crystal Engineering Institute of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China Institute of Molecular and Crystal Engineering Institute of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China Institute of Molecular and Crystal Engineering Institute of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China

A two-dimensional network compound [Ce(DMF)4(H2O)][α-BW12O40]·H2O·(HDMA)2 (HDMA = protoned dimethylamine, DMF = N,N-dimethylformamide) was synthesized from α-H5BW12O40·nH2O, Ce(NO3)3·6H2O and DMF and characterized by IR, UV spectra and TG-DTA. The result of the X-ray single crystal diffraction indicates that the crystal is monoclinic, space group P21/n, with unit cell dimensional: a = 1.1983(3), b = 2.4216(5), c = 1.9517(4) nm, β = 92.91(3)°, Z = 4, R1 = 0.07710, wR2 = 0.1416. Structural analysis indicates that every [Ce(DMF)4(H2O)]3+ building block is surrounded by three adjacent [α-BW12O40]5- polyanions, meanwhile, every [α-BW12O40]5- polyanion interconnects with three neighboring [Ce(DMF)4(H2O)]3+ subunits, by making use of which two-dimensional network structure can be constructed. The result of thermogravimetric analysis manifests that the title compound has two-stage weight loss and the decomposition temperature of the title polyanionic framework is 560℃ . The electrochemical analysis shows the title polyanion has three-step redox processes in the pH = 4―7 media.

关键词： borotungstic acid, network structure, polyoxometalates, crytal structure.

Synthesis and crystal structure of an organic-inorganic complex [Cu(DMF)_3(H_2O)_2]_2[SiMo_(12)O_(40)]·2H_2O

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Rare Metals 2007年第4期26卷 377-384页

作者： wang jingping DU Xiaodi DUAN Xianying NIU Jingyang Institute of Molecule and Crystal Engineering School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China

The synthesis and crystal smacture of an polyoxometalate-based organic-inorganic complex [Cu（DMF）3（H2O）212[SiMo12O40].2H2O （DMF = N, N-dimethyl formamide） is described in this article. It was characterized using elemental analysis, thermal analysis, infrared, ultraviolet, and electron spin resonance spectroscopic studies. The X-ray crystallography analysis showed that the copper centers are pentacoordinated to show the square pyramidal geometry, and the polyanion [SiMo12O40]4- which is semi-coordinated to the copper（I/） centers prevents the existence of a sixth ligand. In addition, the intracationic hydrogen interaction enhanced the stability of the copper coordination cation.

关键词： inorganic chemistry polyoxometalate crystal structure organic-inorganic complex Keggin structure

The spatiotemporal scale effect on vegetation interannual trend estimates based on satellite products over Qinghai-Tibet Plateau

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Journal of Geographical Sciences 2023年第5期33卷 924-944页

作者： MA Dujuan WU Xiaodan wang jingping MU Cuicui College of Earth and Environmental Sciences Lanzhou UniversityLanzhou730000China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiGuangdong611930China University Cooperation of Polar Research Beijing100875China

The trend estimate of vegetation change is essential to understand the change rule of the *** studies were mainly focused on quantifying trends or analyzing their spatial distribution ***,the uncertainties of trend estimates caused by spatiotemporal scale effects have rarely been *** response to this challenge,this study aims to investigate spatiotemporal scale effects on trend estimates using Moderate-Resolution Imaging Spectroradiometer(MODIS)Normalized Difference Vegetation Index(NDVI)and Gross Primary Productivity(GPP)products from 2001 to 2019 in the Qinghai-Tibet Plateau(QTP).Moreover,the possible influencing factors on spatiotemporal scale effect,including spatial heterogeneity,topography,and vegetation types,were *** results indicate that the spatial scale effect depends more on the dataset with a coarser spatial resolution,and temporal scale effects depend on the time span of ***,the trend estimates on the 8-day and yearly scale are much closer than that on the monthly *** addition,in areas with low spatial heterogeneity,low topography variability,and sparse vegetation,the spatiotemporal scale effect can be ignored,and vice *** results in this study help deepen the consciousness and understanding of spatiotemporal scale effects on trend detection.

关键词： spatiotemporal scale effect satellite dataset trend estimates NDVI influencing factors GPP

Self-assembly of DNA molecules at bio-interfaces and their emerging applications for biomedicines

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Nano Research 2023年第12期16卷 13014-13028页

作者： Jing Li jingping wang Ling Chen Yuhang Dong Haonan Chen Guangjun Nie Feng Li College of Chemistry Beijing University of Chemical TechnologyBeijing 100029China CAS Center for Excellence in Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China

Interfacial assembly has been intensively investigated in fabricating biomaterials and nanodevices for various ***,due to the precise sequence programmability,unique molecular recognition ability,and good biocompatibility,deoxyribonucleic acid(DNA)has been explored as superior building blocks to assemble at bio-interface for manipulating biological *** the best of our knowledge,the advances in this area have not been systematically *** provide an overview of the area,in this review,the recently developed DNA assembly strategies on bio-interfaces were well summarized,and their representative works are exampled to illustrate how to rationally and elaborately design DNA molecules to realize functional integration and emerging of novel biological functionalities with high controllability and ***,the biomedical applications of DNA assembly at bio-interface are categorially *** fascinating and unique advantages of DNA assembly systems are fully discussed in the exemplified applications to show the distinguished perspective of DNA in the future *** the end of this review,the current limitations and challenges in applications and potential improvement strategies for DNA assembly at bio-interface are fully *** future development direction is *** envision that this review will help scientists in the interdisciplinary fields gain a more comprehensive understanding of the DNA assembly at bio-interface,and therefore jointly promote the advances in this field.

关键词： deoxyribonucleic acid nanotechnology self-assembly interfacial assembly biomedicine

Evaluation of several recently developed sampling strategies within the coarse pixel scale for validation of coarse-resolution satellite albedo products

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International Journal of Digital Earth 2022年第1期15卷 2319-2334页

作者： Rongqi Tang Xiaodan Wu jingping wang Qicheng Zeng Zheng Li Jianguang Wen College of Earth and Environmental Sciences Lanzhou UniversityLanzhouPeople’s Republic of China State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China

Due to the spatial heterogeneity and the spatial scale mismatch between in situ and satellite-based measurements,optimal ground sampling should be made to increase the representativeness of in situ observations. Therefore,many ground sampling strategies have been proposed,but their performance within the coarse pixel has not been evaluated. Hence,this study evaluated four typical methods regarding their ability to obtain pixel scale ground ‘truth’. Random combination (RC) performs best,with the always fewest samples to satisfy representativeness errors (REs) of 3% in the case of a small number of samples. When the goal of sampling is to obtain in situ measurements with REs close to 0 at the expense of increasing the number of samples,cumulative representativeness sampling (CRS) is more effective than RC in less heterogeneous areas. Geo-statistical model-based sampling (GSS) does not work well because the number of samples within the coarse pixel scale cannot support a robust semi-variogram model. Stratified sampling (SS) is highly dependent on spatial heterogeneity and does not work well in the case of small sample sizes. This study gives important guidance for ground sample deployment within the coarse pixel for validation of coarse-resolution satellite albedo products over a heterogeneous surface.

关键词： Sampling spatial heterogeneity validation representative observations coarse-pixel scale

DL-Serine covalently modified multinuclear lanthanide-implanted arsenotungstates with fast photochromism

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Chinese Chemical Letters 2023年第2期34卷 572-575页

作者： Kangting Zheng Bingxue Niu Cunmeng Lin Yizhen Song Pengtao Ma jingping wang Jingyang Niu Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China

A series of DL-serine covalently modified multinuclear lanthanide implanted arsenotungstates K_(2)[{Ln(H_(2)O)_(7)}_(2){As_(4)W_(44)O_(137)(OH)_(18)(H_(2)O)_(2)(DL-Ser)_(2)}{Ln_(2)(H_(2)O)_(5)(DL-Ser)}_(2)]·65H_(2)O(DL-Ser=DL-serine,Ln=La(1),Ce(2),Pr(3))are *** structure analysis shows that these compounds are isomorphic and contain the basic[{As_(4)W_(44)O_(137)(OH)_(18)(H_(2)O)_(2)(DL-Ser)_(2)}{Ln_(2)(H_(2)O)_(5)(DL-Ser)}_(2)]^(8–)polyoxoanion constituted by two{As_(2)W_(19)O_(59)(OH)_(8)(H_(2)O)}^(6–)subunits,a[W_(6)O_(2)_(3)(OH)_(2)(DL-Ser)_(2)]_(14)–fragment,and two embedded[Ln_(2)(H_(2)O)_(5)(DL-Ser)]^(5+)groups,which further build into one dimensional linear chainlike structure via two peripheral Ln^(3+)*** remarkably,these compounds exhibit rapid photochromic behaviors,which changed color quickly from white(1),yellow(2),green(3)to blue(1),brown(2)and glaucous(3)in ten minutes under UV irradiation,and that the colors gradually recovered in the dark for approximately 22 h.

关键词： Polyoxometalate Arsenotungstate Carboxylate covalently modified Lanthanide Photochromism

Construction of one Ru_(2)W_(12)-cluster and six lacunary Keggin tungstoarsenate leading to the larger Ru-containing polyoxometalate photocatalyst

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Chinese Chemical Letters 2022年第10期33卷 4664-4668页

作者： Huafeng Li Mengnan Yang Zelong Yuan Yahao Sun Pengtao Ma Jingyang Niu jingping wang Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China

Construction of two Ru^(Ⅲ)cations and six lacunary Keggin fragments resulted in a novel Ru_(2)W_(12)-cluster{(RuO_(6))_(2)(WO_(3))_(12)(H_(2)O)_(12)}bridged polyoxometalate,NaH_(11)[(RuO_(6))(AsW_(9)O_(33))_(3){(W_(6)O_(3))(H_(2)O)_(6)}]_(2)53H_(2)O(NaH_(11)·1·53H_(2)O),which represent the largest cluster in all the Ru-containing *** most interesting characteristic is that the symmetry-related Ru_(2)W_(12)-cluster-based hexamers contain two windmill-shaped[(RuO_(6))(AsW_(9)O_(33))_(3){(W_(6)O_(3))(H_(2)O)_(6)}]trimers or the Ru_(2)W_(12) cluster was tightly wrapped by six segments of B-β-AsW_(9)O_(33).The other remarkable feature is that there have one intriguing cubane structure:which is composed of the Ru(1,2)and W(1,28,50,51,52,53)*** oxygenation reactions of anilines to azoxybenzenes was evaluated when NaH_(11)·1·53H_(2)O served as effective catalyst by probing various *** inherent redox property of oxygen-rich polyoxometalate surfaces and high photocatalytic activity of the Ru-containing metal cluster imbedded in NaH_(11)·1·53H_(2)O provide sufficient driving force for the photocatalytic transformation from anilines to *** oxidation of anilines can be realized with higher selectivity to afford various azoxybenzene *** durability test shows that Ru-doping catalyst displays excellent chemical stability during the photocatalytic process.

关键词： Ru-containing polyoxometalate Photocatalyst Oxidation Azoxy compounds Durability

Ln-substituted polytungstates as efficient hetergeneous catalysts for Knoevenagel condensation reaction

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Chinese Chemical Letters 2023年第12期34卷 361-365页

作者： Baijie Xu Ruikun Zhao Zhen Jing Xinyi Ma Hui Zhao Pengtao Ma jingping wang Jingyang Niu Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China

Three isomorphic polytungstates,CsgK_(18)H_(10){[Sm_(2)(H_(2)O)_(4)W_(4)O_(10)(AsW_(9)0_(33))3]_(2)(N(CH_(2)PO_(3))_(2))}:46.5H_(2)O(1),CS_(10)K_(9)H_(18){[Eu_(2)(H_(2)O)_(4)W_(4)O_(10)(AsW_(9)0_(33))_(3)]_(2)(N(CH_(2)PO_(3))_(2))}.41.5H_(2)O(2),Cs_(10)K_(9)H_(18){[Gd_(2)(H_(2)O)_(4)W_(4)O_(10)(AsW_(9)O_(33))_(3)]_(2)(N(CH_(2)PO_(3))_(2))}:46H_(2)O(_(3)),have been successfully synthesized and characterized by routine methods,and demonstrated excellent catalytic activities in Knoevenagel condensation reaction as heterogeneous ***,catalyst 1 achieved higher reaction activity than catalysts 2 and 3,where a satisfactory reaction yield(95%)and high TON value(6380)could be obtained at moderate reaction *** addition,in the scale-up experiment,with the help of catalyst 1,7.8g benzaldehyde and 5.7g ethyl cyanoacetate could transform into corresponding condensation product with a satisfactory yield(83%)and impressive TON value(13.883).

关键词： Polyoxometalates Polytungstates Lanthanide Lewis acid and base sites Knoevenagel condensation reaction