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Two temperature-dependent 2D heterometallic Cd(Ⅱ)-Dy(Ⅲ)coordination polymers exhibiting slow magnetic relaxation and luminescence properties

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Journal of Rare Earths 2023年第4期41卷 613-620页

作者： Zhongyi Li Jiahui Bu Ran Zhang Chi Zhang dongqing wu Bin Zhai College of Chemistry and Chemical Engineering Shangqiu Normal UniversityShangqiu 476000China

Two unique two-dimensional(2D)Cd(Ⅱ)-Dy(Ⅲ)heterometallic coordination polymers,{[DyCd(HPMA)(PMA)_(2)(H_(2)O)_(4)]·2H_(2)O}_n(1)and[DyCd(PAA)(PMA)_(2)(H_(2)O)_(3)]_(n)(2,PAA^(-)=phenylacetate),were prepared successfully based on the phenylmalonic acid(H_(2)PMA).The construction of two polymers is sensitive to the reaction temperature and can be synthesized directionally at room temperature and 90℃,*** 1 and 2 display 2D layer structures that include dinuclear[Dy_(2)]cluster node and Dy(Ⅲ)-based 1D zigzag chain motif *** Dy(Ⅲ)-based units in two structures both are spaced well with the adjacent ones by the diamagnetic Cd(Ⅱ)-based *** magnetic studies reveal that 1 and 2both display slow magnetic relaxation with temperature-dependent relaxation peaks producing an effective energy barrier(Δτ)of 74.5 and 32.1 K,***,the solid-state photophysical properties of 1 and 2 show strong characteristic luminescent emissions of Dy(Ⅲ)ion in the visible region.

关键词： Heterometallic polymers Cd(Ⅱ)-Dy(Ⅲ)ions Slow magnetic relaxation Luminescence Bifunctional material Rare earths

Improvements of marine clay slurries using chemicale-physical combined method(CPCM)

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第2期7卷 220-225页

作者： dongqing wu Wenyu Xu Romy Tjuar Chemilink R&D Centre

In this paper, the effectiveness, applicability and validity of chemicalephysical combined methods（CPCMs） for treatment of marine clay （MC） slurries were evaluated. The method CPCM1 combineschemical stabilization and vacuum preloading （VP）, while CPCM2 is similar to CPCM1 but includes boththe application of surcharge and use of geo-bags to provide confinement during surcharge *** key advantage of CPCM2 using geo-bags is that the surcharge can be immediately applied on thechemically stabilized slurries. Two types of geo-bags were investigated under simulated land filling anddyke conditions, respectively. The test results show that the shear strength （cu） of treated slurry byCPCM2 is generally much higher than that by CPCM1. Besides, the use of CPCM2 can significantly reducethe treatment time due to the short drainage paths created by geo-bags. Overall, CPCM2 allows fasterconsolidation and higher preloading that help to achieve higher mechanical properties of the stabilizedslurry. There are consistent relationships between cU and water content of slurries treated by *** important observations were also made based on comparisons of experimental data. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Chemical e physical combined method(CPCM) Soil improvement Marine clay(MC) slurry Land reclamation Chemical stabilization Vacuum preloading(VP) Geo-bags Surcharge

One-step preparation of novel conjugated porous polymer with tubular structure

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Science China Chemistry 2013年第8期56卷 1112-1118页

作者： ZHUANG XiaoDong ZHANG Yi CAO ChengAn ZHANG Fan wu dongqing FENG XinLiang Institute of Advanced Organic Materials School of Chemical and Chemical EngineeringShanghai Jiao Tong University Max Planck Institute for Polymer Research

A shape-persistent dendritic molecule,tris(4-(2,7-dibromo-9-phenyl-9-fluoren-9-yl)phenyl)amine (TF-6Br),has been readily synthesized in high yield through a concise Friedel-Crafts reaction from triphenylamine and 2,7-dibromo(9-phenyl-fluoren-9-ol).It was further employed as the key building block to achieve the synthesis of conjugated porous polymer via Sonogashira coupling with 1,*** experimental reaction conditions,the resulting porous polymer shows exceptionally nanotubular morphology,which further allows for a template-free synthesis of porous carbon nanotubes via thermal treatment at high *** obtained nitrogen-doped carbon nanotubes feature with an improved porosity and high surface area.

关键词： fluorene Friedel-Crafts reaction porous polymer carbon nanotube

Synthesis and Physical Properties of Benzopyridazine-Based Conjugated Molecules

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Chinese Journal of Chemistry 2013年第11期31卷 1397-1403页

作者： Yuezeng Su Wei Xu Feng Qiu dongqing wu Ping Liu Minzhao Xue Fan Zhang School of Aeronautics and Astronautics Shanghai Jiao Tong University Shanghai 200240 China School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China

A series of novel organic conjugated molecules （5a--5d） comprising 2,3-benzopyridiazine as electron-with- drawing core and thiophene derivatives as electron-donating arms have been synthesized successfully in good yields. The ultraviolet-visible （UV-Vis） absorption spectra and fluorescence spectra of 5a--5d revealed that the optical properties are strongly influenced by the interactions between nitrogen and sulfur atoms in the conjugated backbone, as well as the position of the alkyl chains in the thiophene rings. The experimental results and theoretical calculation data clearly indicated that the band gap and the energy levels of LUMO and HOMO could be fine-tuned by the po- sition of alkyl chains in the thiophene rings. Thus, the structure-property correlation of this class of conjugated molecules can be well established.

关键词： benzopyridiazine heterocycles conjugated molecules optoelectronic properties

A New Three-Dimensional Cyano-Bridged Ferrimagnet Built from [MoⅢ（CN）7]4- Building Block

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A New Three-Dimensional Cyano-Bridged Ferrimagnet Built from...

Tuning the Single Ion Magnetism in Seven-Coordinate YbⅢ Complexes with Distorted D5h Coordination Geometry

中国化学会第九届全国无机化学学术会议

作者： dongqing wu Xinyi Wang State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresSchool of Chemistry and Chemical EngineeringNanjing University

The search for new coordination assemblies exhibiting long-range magnetic ordering has attracted much attention over the past few decades.[1]Among them,cyanide-based transition metal materials has been one of the major research *** assemblies derived from[M（CN）6]3-（M=Cr,Fe,Co）and[M（CN）8]3/4-（M=Mo,W）building blocks and various transition metal or rare earth metal ions have been extensively explored.[2,3]In contrast to the highly symmetrical hexa-and octacyanometallate building blocks,the geometry of the heptacyanometallates block can lead to the formation of low-symmetry extended networks,which is an important feature for designing high-temperature molecular magnets with interesting anisotropic magnetic properties.[4]While,because of handling difficulties,low-symmetry extended heptacyanometalate-based magnets are less commonly *** introduction dimethylamine cation,we synthesized a 3D magnet based on[MoⅢ（CN）7]4-.Magnetic investigations revealed that the compound ordered ferrimagnetically with a small hysteresis effect.

关键词： heptacyanomolybdate ferrimagnet counterion

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Tuning the Single Ion Magnetism in Seven-Coordinate YbⅢ Com...

新加坡固体废物循环利用于填海造地技术的研究进展

中国化学会第八届全国配位化学会议

作者： dongqing wu Yiquan Zhang Xinyi Wang State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University Jiangsu Key Laboratory for NSLSCS School of Physical Science and Technology Nanjing Normal University

It has become increasingly obvious that high magnetic anisotropy is the most critical requirement for an SMM since the reports of double-decker phthalocyanine Tb SIMs and SIMs including 3 d metal ions with certain oxidation states and geometries.2 The dynamic magnetic relaxation behaviour is extremely sensitive to subtle and small structural variations in the metal coordination environment that directly determine the nature and magnitude of the local single-ion magnetic *** the tuning of mole ratio of reactants,we prepared two sevencoordinate compounds[Yb(H L)(DMF) Cl]·DMF·2 H O(1) and[Yb(H L)(DMF) Cl]·H L(2) with pentagonal bipyramidal Yb *** characterization indicates that changes of the mole ratio of reactants result in different guset molecules in the *** 1 and 2 have the same magnetic building block[Yb(H L)(DMF) Cl]except some subtle differences in the local coordination geometry symmetry of Yb *** data analysis reveals that the subtle structure variations trigger remarkable distinct slow magnetic relaxation processes of compounds 1 and *** further understand the different magnetic behaviors,the magnetic anisotropy of Ybcenters in 1 and 2 were studied by ab initio calculations,which is consistent with the experimental observations.

关键词： single-ion magnets YbⅢ D5h

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环境科学研究 2018年第7期31卷 1174-1181页

作者：武冬青郭琳凯密林克科技集团凯密林克科技研发中心

近年来,经济快速发展使得包括新加坡在内的许多沿海国家和地区土地需求量增多,每年的填海规模不断增大,传统的砂石填料已无法满足需求.与此同时,城市固体废物也随着城市化发展而大量产生,其中以生活垃圾焚烧后残留的底渣、海洋淤泥以及... 详细信息

近年来,经济快速发展使得包括新加坡在内的许多沿海国家和地区土地需求量增多,每年的填海规模不断增大,传统的砂石填料已无法满足需求.与此同时,城市固体废物也随着城市化发展而大量产生,其中以生活垃圾焚烧后残留的底渣、海洋淤泥以及建筑工程废土数量尤为庞大.针对世界各国(如丹麦、德国、荷兰等)对固体废物的处置和循环利用以及相关环境标准进行比较说明,并以此为基础介绍采用"化学物理复合法(CPCM)"将新加坡淤泥和垃圾焚烧底渣转化为"淤泥-底渣垃圾材料矩阵(MC-IBA Matrix)"来进行填海造地的"新生土"技术.对化学处理后的新加坡海洋淤泥和生活垃圾焚烧底渣混合物,采用室内三维真空预压和逐级堆载两种不同物理方法来进行加固处理,然后对生成的矩阵材料进行工程测试并依照欧盟与美国的标准进行重金属浸出试验.结果表明:生成的材料矩阵其地基允许承载力在4~6个月内可达15 t/m2,高于一般港口要求(8~12 t/m2).与丹麦No.1662法令和LAGA德国道路工程材料质量标准比较,此材料的重金属浸出值符合其工程材料标准;与荷兰土壤质量法令中工业土壤质量标准相比,此材料符合工业用土标准.工程及环境试验结果均表明了"新生土"作为填海材料的可行性和优越性.从环保角度而言,"新生土"技术中潜在的重金属污染可控,又可缓解日益紧张的填埋场地;从工程角度来看,在较短时间内产生较高地基允许承载力,减少了传统高价砂石的使用,降低工程的时间和成本.因此,对土地有限的国家和地区来说,该绿色技术可解决缺少填埋场用地和填海材料的双重难题.

关键词：城市生活垃圾淤泥焚烧底渣淤泥-底渣垃圾材料矩阵化学物理复合法 “新生土” 填海造地

饱和烷烃的热力学性质与分子结构的拓扑相关性研究

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兰州大学学报（自然科学版） 2000年第2期36卷 77-83页

作者：安红钢吴冬青张掖师范高等专科学校化学系甘肃张掖734000

根据拓扑学原理 ,运用图论方法 ,以计算机为工具 ,对饱和烷烃的分子结构信息进行分析处理 ,定义了一个表征分子结构信息的内聚力指数 F ,并和拓扑指数 W,P一道 ,应用于微观结构与物性关系的研究之中 ,与饱和烷烃的热力学性质进行关联拟... 详细信息

根据拓扑学原理 ,运用图论方法 ,以计算机为工具 ,对饱和烷烃的分子结构信息进行分析处理 ,定义了一个表征分子结构信息的内聚力指数 F ,并和拓扑指数 W,P一道 ,应用于微观结构与物性关系的研究之中 ,与饱和烷烃的热力学性质进行关联拟合 ,给出了相应的定量关系式 .

关键词：饱和烷烃热力学性质分子结构拓扑相关性

化学–物理复合法在海底淤泥填海造地工程中的应用

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岩石力学与工程学报 2013年第9期32卷 1779-1784页

作者：武冬青董志良徐文雨新加坡凯科发展研究院新加坡739462 中交四航工程研究院广东广州510230

在凯科发展研究院多年前率先提出并倡导的采用化学–物理复合法来加快淤泥等软土的固结速度和大幅度提高其固化效果的基础上,联合中交四航工程研究院最新的真空预压技术,以珠江三角洲淤泥为例对化学处理后的高含水率淤泥进行室内三维真... 详细信息

在凯科发展研究院多年前率先提出并倡导的采用化学–物理复合法来加快淤泥等软土的固结速度和大幅度提高其固化效果的基础上,联合中交四航工程研究院最新的真空预压技术,以珠江三角洲淤泥为例对化学处理后的高含水率淤泥进行室内三维真空预压排水模型试验,并同步进行常规的真空预压试验。试验结果表明,用真空预压法来辅助化学加固后的淤泥,在沉降速率上明显大于常规真空预压的速率;在相同的固结时间内,复合法所取得的无侧限抗压强度均远远高于单一真空预压法所取得的强度;同时在用新加坡海洋淤泥进行的相关同步试验中,复合法所取得的数倍高的抗剪强度也进一步验证该方法的有效性及优越性。因此,这个化学–物理复合法对于加固淤泥等软土地基,无论在学术上还是在大面积填海造地工程实践中均有广阔的发展和应用空间。

关键词：土力学淤泥加固造地化学固化真空预压化学-物理复合法绿色环保可持续性